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. 2023 Feb 22;16(3):339. doi: 10.3390/ph16030339

Asymmetric Synthesis of US-FDA Approved Drugs over Five Years (2016–2020): A Recapitulation of Chirality

Rekha Tamatam 1,2, Dongyun Shin 1,2,*
Editor: Angela De Simone
PMCID: PMC10052577  PMID: 36986439

Abstract

Chirality is a major theme in the design, discovery, and development of new drugs. Historically, pharmaceuticals have been synthesized as racemic mixtures. However, the enantiomeric forms of drug molecules have distinct biological properties. One enantiomer may be responsible for the desired therapeutic effect (eutomer), whereas the other may be inactive, interfere with the therapeutic form, or exhibit toxicity (distomer). Classical chemical synthesis usually leads to a racemic mixture unless stereospecific synthesis is employed. To meet the requirements of single-enantiomeric drugs, asymmetric synthesis has evolved at the forefront of drug discovery. Asymmetric synthesis involves the conversion of an achiral starting material into a chiral product. This review emphasizes the methods used for synthesizing FDA-approved chiral drugs during 2016–2020, with a special focus on asymmetric synthesis by means of chiral induction, resolution, or chiral pool.

Keywords: FDA, approve, drug, chiral, asymmetric, synthesis

1. Introduction

1.1. Background

Chirality is an all-encompassing phenomenon [1]. The earliest scientific evidence for chirality was found by Biot in 1815 while discovering the optical rotation of camphor [2]. In 1848, Louis Pasteur discovered that two tartaric acid molecules with the same properties differed in the sign of their optical rotation [3]. In general, this fundamental discovery was the basis for the development of stereochemistry and, particularly, the phenomenon of “chirality”. In nature, both macroscopic as well as microscopic objects can be chiral [4]. A molecule is described as chiral when it can exist in two forms, enantiomers, which have the same chemical structure but are non-superimposable mirror images of each other [5]. The human body is naturally composed of chiral amino acids, sugars, enzymes or receptors, and nucleic acids. Enzymes that are chiral only bind to the enantiomer that has the exact groups that fit into their binding site. Hence, each enantiomer, with respect to its configuration, has a specific action in the body and is selectively metabolized [6]. For instance, thalidomide was initially sold as a racemic drug for the treatment of women with morning sickness; however, it also had a teratogen effect and was subsequently withdrawn from the market. The R-enantiomer showed a positive therapeutic effect, whereas the S-enantiomer resulted in the development of birth defects [7] (Figure 1).

Figure 1.

Figure 1

Existence of chirality in the human body.

1.2. Chirality in FDA Drugs

Our understanding of the concept of chirality has played an essential role in the application of chiral bioactive compounds in pharmaceuticals, agrochemicals, flavors, and fragrances [8,9,10]. Chiral drugs offer several benefits, including that (1) chiral drugs can have higher potency compared to their non-chiral counterparts due to better pharmacokinetic and pharmacodynamic properties; (2) by isolating a specific enantiomer, chiral drugs can reduce unwanted side effects; (3) chiral drugs can enhance drug delivery by targeting specific enzymes or receptors; and (4) using a single enantiomer can reduce the cost of production and lead to lower drug prices for patients. In recent years, the trend in chiral drug discovery has shifted toward the development of single enantiomer drugs. This trend is driven by several factors: increased understanding of the importance of chirality in drug action and toxicity; advancements in analytical techniques that enable the separation and characterization of enantiomers; the need for more effective and safer drugs, as well as the potential for improved patent protection and market exclusivity; and increased regulatory focus on the safety and efficacy of chiral drugs. Overall, the trend in chiral drug discovery is toward the development of single enantiomer drugs, which offer the potential for improved safety, efficacy, and cost-effectiveness.

Since the FDA’s 1992 policy [11], the synthesis of single enantiomers has gained more attention than that of racemic drugs. About 56% of the pharmaceuticals available in the market and used in therapy are chiral, and amongst those drugs, 88% are administered as racemates [12]. As of 2001, racemic drugs can no longer be registered. As drugs can have structural homology across similar biological targets [13], it is widely believed that knowledge of new chemical entities and approaches to their construction will enhance our ability to discover new drugs more efficiently. In order to reduce the toxicity and side effects associated with the inactive enantiomer, the synthesis of enantiomerically pure compounds is essential. In this context, chirality has become an important challenge in the synthesis of drugs [14]. This review presents the synthetic routes for 89 new molecular entities approved by the FDA within the period of 2016–2020. The synthetic sequences described in this review have all been previously reported in patents or articles and represent the process scale or discovery routes of potential chiral drugs. In recent years, the number of chiral drugs approved has been growing in number. For instance, 20 out of the 35 pharmaceuticals approved by the FDA in 2020 are chiral [15]. A chiral drug can be synthesized from commercially available substrates (with stereocenters) or a chiral pool (naturally occurring substrates). Other ways to develop a chiral drug candidate are by employing a chiral auxiliary, using a chiral reagent, or by resolving the racemic precursor. The purpose of this review article is to analyze the recent chiral drugs and highlight the importance of asymmetric synthesis in biologically active compounds, and pharmaceuticals in particular.

2. Methodology

Data for the study were collected from the online database of the FDA under the category of novel drug approval from 2016 to 2020. All drugs are listed under the following parameters: name of the drug, active ingredient, pharmaceutical class of drug, indication for use in the patient, and number of chiral centers. In addition, a literature search was conducted using electronic databases such as PubMed, Annual Reports, Science Direct, and Drug Bank. The structures of the chiral drugs by year are shown in Figure 2, Figure 3, Figure 4, Figure 5 and Figure 6.

Figure 2.

Figure 2

Structure of chiral drugs approved in 2016.

Figure 3.

Figure 3

Structure of chiral drugs approved in 2017.

Figure 4.

Figure 4

Structure of chiral drugs approved in 2018.

Figure 5.

Figure 5

Structure of chiral drugs approved in 2019.

Figure 6.

Figure 6

Structure of chiral drugs approved in 2020.

These drugs were categorized based on the method by which chirality was induced during the manufacturing process, as follows (Figure 7):

  1. Chiral pool approach: Synthesis from naturally occurring or chiral substrates;

  2. Chiral resolution: Resolving the racemic mixture at any stage of synthesis;

  3. Asymmetric synthesis: By adopting a chiral auxiliary, a chiral catalyst, or a chiral reagent.

Figure 7.

Figure 7

Classification of drugs on basis of their chiral induction.

Chirality can be induced at any stage, either as a fragment or from an achiral substrate. Due to the large size of the dataset, only the step where chirality is being introduced is discussed here. Starting from drugs with one chiral center, a year-wise classification is presented.

3. Discussion

3.1. Drugs with One Chiral Center

3.1.1. Lifitegrast (2016)

Lifitegrast, developed by SARcode Bioscience (Brisbane, CA 94005 USA) [16], is marketed for the treatment of dry eye disease [17]. The total synthesis of Lifitegrast is carried out in 10 steps, starting from the commercially available chiral substrate 3-bromo-l-phenylalanine (A1). Lifitegrast is obtained in 88% yield (Scheme 1) [18].

Scheme 1.

Scheme 1

Synthesis of Lifitegrast.

3.1.2. Acalabrutinib (2017)

Acalabrutinib, developed by Acerta Pharma, is used for the treatment of mantle cell lymphoma (MCL) [19]. Starting from the 4-bromo benzoic acid (A3), four steps are carried out to obtain the intermediate, A4. Commercially available chiral proline derivative, A5, undergoes amidation with A4 via acid chloride to yield acalabrutinib in 86% yield (Scheme 2) [20,21].

Scheme 2.

Scheme 2

Synthesis of Acalabrutinib.

3.1.3. Pemafibrate (2017)

Pemafibrate, developed by Kowa Pharmaceuticals, is used for the treatment of hyperlipidemia [22]. Chiral fragment A9 is synthesized from enantiopure (S)-2-hydroxybutyrolactone (A7) via a ring-opening reaction in the presence of trimethylsilyl iodide. The hydrogenative reduction of A8 and triflate addition using 2,6-lutidine produces A9. A9 undergoes inversion of the configuration using potassium carbonate and acetonitrile, resulting in the formation of pemafibrate in 75% yield (Scheme 3) [23].

Scheme 3.

Scheme 3

Synthesis of Pemafibrate.

3.1.4. Letermovir (2017)

AiCuris developed letermovir for the treatment of cytomegalovirus infections [24]. A stereogenic center is installed in letermovir during the urea cyclization step. Urea (A11) undergoes cyclization in a biphasic mixture of aqueous K3PO4 and toluene in the presence of a cinchona-alkaloid-based phase-transfer catalyst and results in the formation of quinazolinone racemate (A12) (Scheme 4) [25].

Scheme 4.

Scheme 4

Synthesis of Letermovir.

3.1.5. Netarsudil (2017)

Aerie Pharmaceuticals developed netarsudil for the treatment of ocular hypertension [26]. The Evans oxazolidinone (A15) acts as a chiral auxiliary and is later removed in the presence of hydrogen peroxide. Diester A14 undergoes regioselective hydrolysis, followed by acid chloride formation and amidation to give the ester derivative, A16. Treatment of Evans oxazolidinone compounds with LiHMDS and Boc-protected benzotriazolylmethylamine produces A17, through which essential stereochemistry for netarsudil is installed (Scheme 5) [27].

Scheme 5.

Scheme 5

Synthesis of Netarsudil.

3.1.6. Niraparib (2017)

Niraparib, discovered by Merck & Co. (Rahway, NJ, USA) and developed by Tesaro, is used for the treatment of peritoneal cancer [28]. Niraparib, having one chiral center, is obtained from piperidine subunit A23, which is synthesized from bromobenzene (A19). The bisulfite adduct, A21, undergoes a transaminase reaction catalyzed by the ATA-302 enzyme and co-catalyzed by pyridoxal-5-phosphate (PLP), yielding chiral piperidine (A22) (Scheme 6) [29,30,31,32].

Scheme 6.

Scheme 6

Synthesis of Niraparib.

3.1.7. Lorlatinib (2018)

Lorlatinib, developed by Pfizer, is an oncological drug [33]. Lorlatinib, a macrocycle, is constructed from chiral alcohol intermediate A25. This key step involves enantioselective reduction using a biocatalyst (Scheme 7) [34].

Scheme 7.

Scheme 7

Synthesis of Lorlatinib.

3.1.8. Elobixibat Hydrate (2018)

EA Pharma and Mochida developed elobixibat hydrate for the treatment of chronic idiopathic constipation [35]. The single chiral carbon is generated during acid-ester coupling in the presence of TBTU and methyl (R)-2-amino-2-phenylacetate (A28) (Scheme 8) [36].

Scheme 8.

Scheme 8

Synthesis of Elobixibat hydrate.

3.1.9. Tezacaftor (2018)

Discovered and developed by Vertex Pharmaceuticals [37,38], tezacaftor is a broad-acting cystic fibrosis transmembrane conductance regulator (CFTR). The scaled synthesis of tezacaftor (Scheme 9) [39] begins with 3-fluoro-4-nitroaniline (A31). Regioselective bromination with N-Bromosuccinimide (NBS) produces the intermediate, A32. Commercially available (R)-glycidyl benzyl ether (A33) induces chirality on aniline by acid-catalyzed ring opening, followed by reduction of the nitro group to give A34. Subsequent steps, including Sonogashira coupling, Larock-type cyclization, and acid-amine coupling, give tezacaftor in 84% yield.

Scheme 9.

Scheme 9

Synthesis of Tezacaftor.

3.1.10. Pyrotinib Maleate (2018)

Hengrui Pharmaceuticals developed pyrotinib maleate [40], a pan-ErbB receptor tyrosine kinase inhibitor, which is used for the treatment of metastatic breast cancer. The kilogram-scale synthesis of pyrotinib maleate is shown in Scheme 10. Chiral fragment A37 is synthesized from N-Boc-d-prolinol (A36) in four steps [41].

Scheme 10.

Scheme 10

Synthesis of Pyrotinib maleate.

3.1.11. Encorafenib (2018)

Encorafenib, in combination with binimetinib, is used for the treatment of metastatic melanoma [42]. Currently, encorafenib is marketed by Pfizer. Chirality is introduced as follows: (S)-(−)-1,2-diaminopropane dihydrochloride (A39) is treated with benzyl chloroformate and methyl chloroformate in the presence of a base, resulting in the carbamate derivative, A40. Upon hydrogenation, the chiral subunit, A41, is obtained (Scheme 11) [43].

Scheme 11.

Scheme 11

Synthesis of Encorafenib.

3.1.12. Duvelisib Monohydrate (2018)

Duvelisib monohydrate, initially developed by Intellikine and later licensed to Verastem Oncology [44], is used in the treatment of both chronic lymphocytic leukemia and small lymphocytic lymphoma [45,46]. The kilogram-scale synthesis of duvelisib disclosed by Intellikine is discussed in Scheme 12 [47]. Weinreb amide A44 treated with n-hexyl lithium is combined with benzamide A43 to form the chiral isoquinoline A45 in four steps. In the last step, salt resolution is performed with d-tartaric acid in methanol, and then with ammonium hydroxide to enhance the enantiopurity of A45.

Scheme 12.

Scheme 12

Synthesis of Duvelisib monohydrate.

3.1.13. Elagolix Sodium (2018)

Elagolix sodium, used for treating women with endometriosis, was developed by Abbvie and Neurocrine Biosciences [48]. Similar to duvelisib monohydrate, chirality is induced during the alkylation of uracil with mesylate derivative; the latter compound is synthesized by the reaction of (−)-N-Boc-d-α-phenylglycinol with methanesulfonyl chloride (Scheme 13) [49].

Scheme 13.

Scheme 13

Synthesis of Elagolix sodium.

3.1.14. Tegoprazan (2018)

Tegoprazan, initially discovered by Pfizer and further developed by RaQualia Pharmaceuticals and CJ Healthcare, is used for the treatment of gastroesophageal reflux disease (GERD) [50]. The scalable synthesis of tegoprazan is given in Scheme 14 [51]. The introduction of an enantiopure chromanol side chain A53 on the benzimidazole ring is the key step of the synthesis that occurs in the presence of tri-n-butylphosphine with 1,1′-(azodicarbonyl)dipiperidine (ADDP). Then, 3,5-difluorophenol (A50) undergoes condensation with methyl propiolate to afford enol ethers (A51) in both the E and Z forms (1:1 mixture). Hydrogenation, followed by intramolecular Friedel–Crafts acylation and asymmetric reduction with ozaborolidine catalyst (A52), produces chromanol (A53). Finally, recrystallization of the latter compound yields the enantiopure chiral subunit, A53.

Scheme 14.

Scheme 14

Synthesis of Tegoprazan.

3.1.15. Alpelisib (2019)

Novartis Pharmaceuticals developed alpelisib [52,53]. It is used for the treatment of metastatic breast cancer. The chiral center is introduced by l-proline amide A56 on the imidazole ring of A55 in the presence of triethylamine during the final step of synthesis (Scheme 15) [54,55,56].

Scheme 15.

Scheme 15

Synthesis of Alpelisib.

3.1.16. Solriamfetol (2019)

Solriamfetol, developed by SK Biopharmaceuticals [57], is used for the treatment of Ehlers–Danlos syndromes (EDS) associated with obstructive sleep apnea (OSA) and narcolepsy [58]. The kilogram-scale synthesis of solriamfetol is shown in Scheme 16 [59]. Solriamfetol is synthesized in 89% yield in a single step from d-phenylalaninol (A58) and sodium cyanate in the presence of acid.

Scheme 16.

Scheme 16

Synthesis of Solriamfetol.

3.1.17. Pretomanid (2019)

Pretomanid, an antimycobacterial agent, is used to treat tuberculosis (TB). It is the first TB drug to be developed by TB Alliance [60]. Epoxide (A61) plays its role as a chiral substrate by coupling with prochiral nitroimidazole (A60) in the presence of DIPEA, affording A62 (Scheme 17) [61].

Scheme 17.

Scheme 17

Synthesis of Pretomanid.

3.1.18. Zanubrutinib (2019)

BeiGene, Inc. (Cambridge, MA, USA) developed zanubrutinib for the treatment of mantle cell lymphoma [62]. In contrast to the chiral pool approach discussed above, Zanubrutinib is the first drug that is produced by chiral resolution. Zanubrutinib is obtained in its pure enantiomeric form via resolution methodology by treating it with l-dibenzoyltartaric acid (LDBTA) (Scheme 18) [63].

Scheme 18.

Scheme 18

Synthesis of Zanubrutinib.

3.1.19. Darolutamide (2019)

Darolutamide is used in the treatment of non-metastatic castrate-resistant prostate cancer [64]. It was developed by Orion Corporation and Bayer Healthcare [65]. The key step in the asymmetric synthesis of darolutamide is the insertion of chiral isopropylamine fragment, A67, into the biaryl scaffold in A66, followed by acid-mediated deprotection of the Boc group to generate an intermediate A68 (Scheme 19) [66].

Scheme 19.

Scheme 19

Synthesis of Darolutamide.

3.1.20. Cenobamate (2019)

SK Pharmaceuticals developed cenobamate [67] for the treatment of partial-onset seizures. The enzymatic catalysis presented in Scheme 20 [68] outlines its asymmetric catalytic hydrogenation in the presence of Rhodotorula mucilaginosa, an oxidoreductase.

Scheme 20.

Scheme 20

Synthesis of Cenobamate.

3.1.21. Avapritinib (2020)

Blueprint Medicines developed avapritinib [69] for the treatment of metastatic gastrointestinal tract cancers. The chiral resolution by means of supercritical fluid chromatographic separation of intermediate, A73, produces enantiopure avapritinib in 68% yield (Scheme 21) [70].

Scheme 21.

Scheme 21

Synthesis of Avapritinib.

3.1.22. Berotralstat (2020)

Berotralstat is used to treat the prophylaxis of hereditary angioedema (HAE) attacks [71]. Following the same procedure as avapritinib, berotralstat is synthesized in its pure enantiomeric form by means of supercritical fluid chromatography in the final step (Scheme 22) [72].

Scheme 22.

Scheme 22

Synthesis of Berotralstat.

3.1.23. Lonafarnib (2020)

Lonafarnib is used for the treatment of Hutchinson–Gilford progeria syndrome (HGPS) [73]. Unlike berotralstat, chirality in lonafarnib is obtained by chiral separation. Intermediate A77 upon reduction with diisobutylaluminium hydride (DIBAL) followed by chiral separation resulted in the formation of the chiral subunit, A78, with one stereocenter. These successive steps yield lonafarnib (Scheme 23) [74].

Scheme 23.

Scheme 23

Synthesis of Lonafarnib.

3.1.24. Osilodrostat (2020)

Osilodrostat, used for treating Cushing’s disease, is a 11β-hydroxylase inhibitor [75]. Chiral osilodrostat is generated in a manner similar to that of berotralstat. Chiral HPLC separation of the intermediate A80 directly results in drug formation (Scheme 24) [76].

Scheme 24.

Scheme 24

Synthesis of Osilodrostat.

3.1.25. Oliceridine (2020)

Oliceridine, a central nervous system (CNS) drug, is used to treat moderate-to-severe acute pain [77]. In the total synthesis of oliceridine, the chiral intermediate A83 is obtained by the decarboxylic reaction of A82, followed by SFC chiral separation (Scheme 25) [78].

Scheme 25.

Scheme 25

Synthesis of Oliceridine.

3.1.26. Remimazolam (2020)

Acacia Pharma developed remimazolam, an ultrashort-acting benzodiazepine [79]. Treatment of A85 with the chiral substrate, A86 in chloroform generated the substituted product, which upon base-promoted F-moc deprotection and acetic acid promoted condensation resulted in the formation of cyclized intermediate A87 in three steps (Scheme 26) [80].

Scheme 26.

Scheme 26

Synthesis of Remimazolam.

3.1.27. Ozanimod (2020)

Ozanimod is used to treat relapsing multiple sclerosis [81]. The chiral sulfinamide fragment, A90, acts as a chiral auxiliary group by inserting a chiral center on the indene derivative, A89. Ozanimod is synthesized in successive steps from intermediate A91 (Scheme 27) [82].

Scheme 27.

Scheme 27

Synthesis of Ozanimod.

3.2. Drugs with Two Chiral Centers

3.2.1. Nemonoxacin (2016)

Nemonoxacin was originally developed by Procter & Gamble Pharmaceuticals [83] (P&GP) and co-developed by TaiGen Biotechnology (Asia) and Warner Chilcott (US and Europe). Scheme 28 describes the process-scale synthesis of nemonoxacin [84]. Proline derivative B1, upon esterification, gives an intermediate (B2), which, on treatment with Bredereck’s reagent and hydrogenation, gives chiral subunit B3. Then, simultaneous reduction and treatment with CaCl2 form the diol B4. Aminopiperidine B5 is obtained from this intermediate via sequential mesylation, cyclization, and hydrogenation.

Scheme 28.

Scheme 28

Synthesis of Nemonoxacin.

3.2.2. Brivaracetam (2016)

UCB Pharma developed both brivaracetam and levetiracetam. Brivaracetam is an antiepileptic drug used to treat partial-onset seizures [85,86]. The kilogram-scale synthesis shown in Scheme 29 [87] shows that chirality is achieved by enzymatic resolution with protease C to form fragment B8. Another chiral pool substrate, (S)-2-aminobutanamide (B10), is inserted into the chiral subunit, B9 to form brivaracetam B11.

Scheme 29.

Scheme 29

Synthesis of Brivaracetam.

3.2.3. Beclabuvir (2016)

Bristol Myers Squibb discovered and developed beclabuvir [88]. It is used to treat HCV infections. The chiral cyclopropyl fragment, B13, is generated by the Corey–Chaykovsky reaction using NaH, followed by chiral separation. Beclabuvir is synthesized from intermediate B13 in successive steps (Scheme 30) [89].

Scheme 30.

Scheme 30

Synthesis of Beclabuvir.

3.2.4. Inotuzumab Ozogamicin (2017)

Inotuzumab Ozogamicin, discovered by Lederle Laboratories, is used for the treatment of refractory B-cell precursor acute lymphoblastic leukemia (ALL) [90]. Scheme 31 provides an overview of the chiral pool synthesis of inotuzumab ozogamicin. Fermentation of Micromonospora echinospora sp. Calichenis gave Calicheamicin (B15) [91,92]. The linker (B16) is then coupled to chiral substrate B15 to produce B17. Later, it is conjugated with anti-CD22 mAb G-544 to obtain inotuzumab ozogamicin in 60% yield [93].

Scheme 31.

Scheme 31

Synthesis of Inotuzumab Ozogamicin.

3.2.5. Deutetrabenazine (2017)

Deutetrabenazine has been approved for the treatment of chorea (abnormal involuntary movements) associated with Huntington’s disease [94]. The synthesis of deutetrabenazine is described in Scheme 32 [95]. The reaction of dihydroisoquinoline fragment B19 and quaternary ammonium salt B20 in the presence of a base resulted in the formation of the desired product. Unfortunately, deutetrabenazine is obtained as a racemic mixture (cis-diastereomer) in 67% yield.

Scheme 32.

Scheme 32

Synthesis of Deutetrabenazine.

3.2.6. Vaborbactam (2017)

Rempex Pharmaceuticals discovered vaborbactam, and it was then developed by The Medicines company. Vaborbactam, in combination with meropenem, is used to treat complicated urinary tract infections [96]. The key step in its synthesis is obtaining a pure enantiomeric form by enantioselective lipase resolution of the racemic substrate, B22. Subsequently, the chiral centers are inserted via Matteson homologation (Scheme 33) [97].

Scheme 33.

Scheme 33

Synthesis of Vaborbactam.

3.2.7. Telotristat Ethyl (2017)

Lexicon Pharmaceuticals developed telotristat ethyl, which has two chiral carbons, for the treatment of carcinoid syndrome diarrhea [98]. One of the chiral carbons is implanted from commercially available N-Boc-tyrosine methyl ester B33 and the other, shown in B32, from asymmetric transfer hydrogenation using an Iridium catalyst and ligand B31 (Scheme 34) [99,100].

Scheme 34.

Scheme 34

Synthesis of Telotristat ethyl.

3.2.8. Larotrectinib (2018)

Array BioPharma and LOxo Oncology discovered larotrectinib, which was further developed in collaboration with Bayer AG. It is used to treat solid tumors with neurotrophic receptor tyrosine kinase gene fusions [101]. Ellman’s auxiliary (B36) is responsible for the chirality in larotrectinib. The second stereogenic center is derived from a commercially available pyrrolidinol fragment (Scheme 35) [102].

Scheme 35.

Scheme 35

Synthesis of Larotrectinib.

3.2.9. Glasdegib (2018)

Glasdegib was developed by Pfizer and is used for the treatment of acute myeloid leukemia [103]. Glasdegib is a good example of chiral resolution in drug synthesis. The key chiral substrate, B46, (anti-form) is obtained by dynamic kinetic resolution of the racemic mixture, B44, with transaminase enzyme ATA-306 in the presence of borate buffer (Scheme 36) [104].

Scheme 36.

Scheme 36

Synthesis of Glasdegib.

3.2.10. Talazoparib (2018)

Talazoparib, discovered by BioMarin and developed by Pfizer, is used to treat germline BRCA-mutated HER2-negative metastatic breast cancer [105]. Unlike glasdegib, the synthesis of talazoparib employs supercritical fluid chromatography (SFC) chiral separation to obtain the essential 1,2,4-triazole subunit, B49, which has two chiral centers (Scheme 37) [106,107,108].

Scheme 37.

Scheme 37

Synthesis of Talazoparib.

3.2.11. Ivosidenib (2018)

Agios Pharmaceuticals developed ivosidenib for the treatment of relapsed or refractory acute myeloid leukemia [109]. The Ugi reaction between isonitrile (B51), imine (B52), and chiral acid (B53) results in a racemic intermediate. Crystallization, followed by piperidine treatment, affords diastereomer B54. The crystallization step is considered crucial because the final synthesis of the drug relies on the diastereomer alone (Scheme 38) [110].

Scheme 38.

Scheme 38

Synthesis of Ivosidenib.

3.2.12. Evocalcet (2018)

The Mitsubishi Tanabe Pharma corporation discovered evocalcet and Kyowa Kirin further developed the drug for secondary hyperparathyroidism (SHPT) treatment [111]. The diastereomeric mixture, B58, obtained from N-Boc pyrrolidinol (B56), is treated with triphosgene and tert-butanol to obtain both syn (B59) and anti (B60) diastereomers. These two compounds are separated by chromatography. For this drug, the chromatography approach is predominantly used over the chiral pool approach, as evocalcet, with two chiral centers, is synthesized from the syn-pyrrolidine derivative, B59 (Scheme 39) [111].

Scheme 39.

Scheme 39

Synthesis of Evocalcet.

3.2.13. Baloxavir Marboxil (2018)

Baloxavir marboxil was first approved by Pharmaceuticals and Medical Devices Agency (PMDA) and was further developed by Shionogi Inc. for the treatment of influenza A and B infections [112]. Baloxavir marboxil is constructed from different subunits, including chiral piperazine (B64), benzothiepine (B65), and alkyl chloride side chains. Resolution is carried out via the reaction of piperazine fragment B62 with chiral acid B63. Subsequent recrystallization results in B64 (Scheme 40) [113].

Scheme 40.

Scheme 40

Synthesis of Baloxavir marboxil.

3.2.14. Fosravuconazole l-Lysine Ethanolate (2018)

Eisai Co., Ltd. (Bunkyo City, Tokyo) discovered fosravuconazole l-lysine ethanolate [114], a prodrug of ravuconazole and broad-spectrum antifungal agent. The process-scale synthesis of fosravuconazole is outlined in Scheme 41 [115]. The chiral pool synthesis of fosravuconazole l-lysine ethanolate starts with a single chiral center in lactate (B68) and another is induced from intermediate B69 by Corey–Chaykovsky epoxidation and sequential ring opening in a single step. Ravuconazole is converted into fosravuconazole in three successive steps (Scheme 41) [116].

Scheme 41.

Scheme 41

Synthesis of Fosravuconazole l-lysin ethanolate.

3.2.15. Lumateperone (2019)

Lumateperone is an antipsychotic drug used to treat schizophrenia [117]. In the nine-step synthesis of lumateperone, stereocenters are generated during the reduction of tricyclic indole intermediate B73 with triethylsilyl hydride, followed by treatment with (R)-mandelic acid in methanol. Thus, the formed (S)-mandelic acid diastereomeric salt undergoes free-basing with aqueous NaOH to afford chirally pure cis-indoline B74 (Scheme 42) [118].

Scheme 42.

Scheme 42

Synthesis of Lumateperone.

3.2.16. Tenapanor (2019)

Tenapanor was developed by Ardelyx Inc. to treat irritable bowel syndrome with constipation [119]. Scheme 43 describes the synthesis of tenapanor. The tetrahydroisoquinoline intermediate, B76, generated during the synthesis reacts with linker B77, followed by chiral resolution (SFC separation), resulting in the formation of chiral fragment B78 [120].

Scheme 43.

Scheme 43

Synthesis of Tenapanor.

3.2.17. Lemborexant (2019)

Lemborexant, developed by Eisai Co., Ltd. is used for the treatment of insomnia [121]. Starting with 2-(3-fluorophenyl) acetonitrile (B80), chirality is induced from epoxide B81 by step-by-step substitution, hydrolysis, ring-opening, and ring-closure reactions. Thus, the generated intermediate B82 undergoes reduction with NaBH4, followed by lipase-induced transesterification, eventually leading to the synthesis of lemborexant in five steps (Scheme 44) [122].

Scheme 44.

Scheme 44

Synthesis of Lemborexant.

3.2.18. Cefiderocol (2019)

Shionogi et al. developed cefiderocol, a cephalosporin antibacterial drug. It is used for the treatment of complicated urinary tract infections (cUTI) [123]. Linear synthesis of cefiderocol is shown in Scheme 45 [124]. Chirality is induced by azetidinone ring B88, which was previously synthesized from the phthalimide derivative, B84.

Scheme 45.

Scheme 45

Synthesis of Cefiderocol.

3.2.19. Upadacitinib (2019)

Upadacitinib is used to treat rheumatoid arthritis [125]. Chiral pyrrolidine fragment B94, which is essential for the synthesis of upadacitinib, is obtained by asymmetric hydrogenation of B93 in the presence of a ruthenium catalyst. The latter compound B93 was obtained by the condensation of Cbz-protected glycine ethyl ester B91 and ethyl acrylate B92 in the presence of sodium tertiary butoxide (Scheme 46) [126].

Scheme 46.

Scheme 46

Synthesis of Upadacitinib.

3.3. Drugs with Three Chiral Centers

3.3.1. Tenofovir Alafenamide Fumarate (2016)

Tenofovir alafenamide fumarate was discovered and developed by Gilead for the treatment of chronic hepatitis B viral infections [127]. The reaction of adenine (C1) with (R)-propylene carbonate (C2) affords intermediate C3, with a single chiral center. In successive steps, the monophosphonate ester, C5, is treated with thionyl chloride, and the l-alanine derivative, C6, affords racemic intermediate C7, with two chiral centers. Simulated moving bed chromatography is employed to resolve the racemic mixture and obtain diastereomers. Tenofovir alafenamide fumarate is synthesized from diastereomer C8 and fumaric acid (Scheme 47) [128].

Scheme 47.

Scheme 47

Synthesis of Tenofovir alafenamide fumarate.

3.3.2. Bictegravir (2018)

A combination of bictegravir, emtricitabine, and tenofovir alafenamidecan be used to treat HIV-1 infections [129]. The process-scale synthesis of bictegravir was reported and developed by Gilead (Scheme 48) [130,131]. The late-stage installation of chiral substrate C13 to the pyridone derivative results in bictegravir in three steps. Synamino pentanol (C13) is previously obtained from commercially available cyclopentanoic acid (C10) in six steps. Acid C10 is converted to amide C11, which then undergoes oxidation to form the chiral alcohol subunit, C13.

Scheme 48.

Scheme 48

Synthesis of Bictegravir.

3.3.3. Relebactam (2019)

Relebactam was developed by Merk Sharp & Dohme [132]. Relebactam, imipenem, and cilastin is a drug combination used for the treatment of complicated urinary tract and intra-abdominal infections [133]. Chiral substrate 5-hydroxypiperidine-2-carboxylic acid (C15) undergoes sulfonylation and intramolecular esterification to form the bridged intermediate, C16. Later, ring opening followed by substitution and cyclization with triphosgene gives the chiral bridged intermediate, C20, with three chiral centers (Scheme 49) [134].

Scheme 49.

Scheme 49

Synthesis of Relebactam.

3.3.4. Fam-Trastuzumab Deruxtecan-Nxki (2019)

Daiichi Sankyo and AstraZeneca developed fam-trastuzumab deruxtecan-nxki, an antibody–drug conjugate. The structure is composed of the GGFG linker C23, polycyclic chiral fragment C27, and anti-HER2 monoclonal antibody (mAb). Various stages of inducing chirality in a single drug are shown in Scheme 50 and described below [135]:

  1. The linker C23 with one chiral center is obtained by a chiral pool approach (i.e., amino acid derivative C22 imparts its stereocenter to the drug);

  2. The polycyclic chiral fragment C27 is prepared by [4 + 2] cycloaddition, followed by chiral resolution adopting supercritical fluid chromatography of the racemic intermediate, C26.

Scheme 50.

Scheme 50

Synthesis of Fam-trastuzumabderuxtecan-nxki.

3.3.5. Pralsetinib (2020)

Pralsetinib, developed by Blueprint Medicines, is used in the treatment of metastatic non-small cell lung cancer [136]. The key step during its synthesis is the benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBOP)-stimulated amide coupling between the ester intermediate C29 and the chiral amine fragment C30, to result in a mixture of diastereomers. The last step involves the isolation of pralsetinib by superfluid chromatography (Scheme 51) [137].

Scheme 51.

Scheme 51

Synthesis of Pralsetinib.

3.3.6. Rimegepant (2020)

Biohaven developed rimegepant for the treatment of migraines [138]. The asymmetric synthesis of rimegepant is carried out by the following step-by-step process (Scheme 52) [139]:

  1. Rhodium-catalyzed reduction of pyridine derivative C32 followed by hydroxyl protection with triisopropylsilyl trifluoromethanesulfonate (TIPSOTf) results in a chiral intermediate C33;

  2. Chiral fragment C33 then undergoes coupling with 1-bromo-2,3-difluorobenzene C34 resulting in an intermediate C35 with two stereocenters;

  3. The last chiral center in C36 is obtained by lithium-mediated reduction.

Scheme 52.

Scheme 52

Synthesis of Rimegepant.

3.4. Drugs with Four Chiral Centers

3.4.1. Migalastat Hydrochloride (2016)

Migalastat, also known as d-1-deoxygalactonojirimycin, is used to treat Fabry disease [140]. The kilogram-scale synthesis depicted in Scheme 53 [141] provides a clear example of the chiral pool synthesis of migalastat hydrochloride (D4) from d-galactose (D1).

Scheme 53.

Scheme 53

Synthesis of Migalastat hydrochloride.

3.4.2. Midostaurin (2017)

Midostaurin is used for the treatment of FLT3 mutation-positive Acute Myeloid Leukemia (AML) [142]. Its chiral pool synthesis begins with staurosporine (D5), a molecule produced by fermentation. Acylation of chiral substrate D5 with benzoic anhydride (D6) results in the formation of midostaurin in a single step (Scheme 54) [143].

Scheme 54.

Scheme 54

Synthesis of Midostaurin.

3.4.3. Naldemedine (2017)

Shionogi & Co., Ltd. (Osaka, Japan) developed naldemedine for the treatment of opioid-induced constipation [144]. In addition to naturally occurring compounds initiating chiral synthesis, commercially available naltrexone hydrochloride (D8) affords naldemedine tosylates in 66% yield (Scheme 55) [145].

Scheme 55.

Scheme 55

Synthesis of Naldemedine.

3.4.4. Valbenazine (2017)

Neurocrine Biosciences developed valbenazine for the treatment of tardive dyskinesia in adults [146]. The well-known resolving agent L-tartaric acid (DPTTA) is used to separate (±)-tetrabenazine (D12) to yield (+)-amine D13, which is essential for the formation of valbenazine (Scheme 56) [147].

Scheme 56.

Scheme 56

Synthesis of Valbenazine.

3.4.5. Eravacycline (2018)

Eravacyclin, a tetracycline, is used to treat complicated intra-abdominal infections. Tetraphase Pharmaceuticals discovered and developed eravacycline [148,149,150]. Eravacycline is composed of a chiral isoxazole fragment, D20, and a dibenzyl amine derivative. The D20 preparation involves the two following methods (Scheme 57) [151]:

  1. Ellman sulfinamide auxiliary (D16) is used to convert aldehyde (D15) to sulfinimine (D17), which eventually leads to the formation of the chiral tartarate derivative, D18;

  2. Recrystallization with isopropanol provides pure chiral tricyclic fragment D20 from the corresponding enone derivative, D19.

Scheme 57.

Scheme 57

Synthesis of Eravacycline.

3.4.6. Sarecycline Hydrochloride (2018)

Paratek Pharmaceuticals discovered sarecycline; however, the drug was solely developed by Allergan. It belongs to the tetracycline class of antibiotics and is used for the treatment of inflammatory lesions of acne vulgaris [152]. A semi-synthetic tetracycline antibiotic, sancycline (D22), upon iodination with N-iodosuccinimide and further purification provided the iodosancycline salt, D23, is required for the synthesis of sarecycline hydrochloride (Scheme 58) [153,154,155].

Scheme 58.

Scheme 58

Synthesis of Sarecycline.

3.4.7. Omadacycline (2018)

Discovered and developed by Paratek Pharmaceuticals [156], omadacycline, a tetracycline antibiotic, is used to treat acute bacterial skin infections and community-acquired pneumonia. Analogous to sarecycline, the tetracyclic antibiotic drug minocycline (D25) initiates the synthesis of omadacycline. Condensation with N-(hydroxymethyl)phthalimide in the presence of triflic acid affords a mixture of D26 upon hydrolysis with methyl amine to generate the chiral intermediate, D27 (Scheme 59) [157].

Scheme 59.

Scheme 59

Synthesis of Omadacycline.

3.4.8. Vibegron (2018)

Vibegron was discovered by Merck and developed by Kyorin Pharmaceutical Co., Ltd. (Tokyo, Japan) and Kissei Pharmaceutical Co., Ltd. (Matsumoto, Japan). It is used for the treatment of overactive bladder [158]. The key step in the synthesis of vibegron is to facilitate both the epimerization and reduction of racemic mixtures D30 and D31. Ketoreductase and the cofactor NADPNa are used to form the (R)-isomer D32 (Scheme 60) [159].

Scheme 60.

Scheme 60

Synthesis of Vibegron.

3.4.9. Ubrogepant (2019)

Ubrogepant was developed by Allergan, Inc. It is used to treat migraines in adults [160]. Resolution by means of SFC separation, focused on racemic spiro intermediate D34 resulted in the formation of mono-configurational fragment D35, as depicted in Scheme 61 [161].

Scheme 61.

Scheme 61

Synthesis of Ubrogepant.

3.4.10. Cedazuridine (2020)

Cedazuridine, in combination with decitabine, is used for the treatment of myelodysplastic syndrome [162]. Chiral chromatographic separation of racemic intermediate D38 affords the chiral cedazuridine, D39, in a three-step synthesis (Scheme 62) [163].

Scheme 62.

Scheme 62

Synthesis of Cedazuridine.

3.4.11. Vibegron (2020)

Vibegron is used to treat overactive bladder with symptoms, such as urge urinary incontinence and urinary frequency [158]. Large-scale synthesis of the drugs is outlined in Scheme 63. Chiral amine, D40, generated from hexynoic acid, undergoes acid-amine coupling with another chiral acid, D41, followed by chiral SFC separation, to give the drug in pure form (Scheme 63) [164].

Scheme 63.

Scheme 63

Synthesis of Vibegron.

3.5. Drugs with Five Chiral Centers

3.5.1. Narlaprevir (2016)

Narlaprevir was developed by Schering-Plough Corporation and the Texas Liver Institute and succeeded by R-Pharm Pharmaceuticals. It is an anti-infective drug used for the treatment of hepatitis C virus (HCV) genotype 1 infections [165]. The kilogram-scale synthesis of narlaprevir is presented in Scheme 64 [166,167]. Chirality is induced during the conversion of the acid intermediate E1 to the urea derivative, E2, in the presence of leucine. Another three chiral centers from the bicyclic amine, E3, are introduced by peptide coupling conditions.

Scheme 64.

Scheme 64

Synthesis of Narlaprevir.

3.5.2. Elbasvir (2016)

Merck developed the combination of elbasvir and grazoprevir for the treatment of chronic HCV infections [168]. Elbasvir, which contains five chiral carbons, is shown in Scheme 65. The key step in the synthesis of elbasvir is the asymmetric reduction of imine derivative E6 in the presence of a ruthenium catalyst, E7 [169].

Scheme 65.

Scheme 65

Synthesis of Elbasvir.

3.5.3. Latanoprostene Bunod (2017)

Latanoprostene bunod was discovered by the NicOx–Pfizer collaboration and developed by Bausch and Lomb. It is used to reduce intraocular pressure in patients with open-angle glaucoma or ocular hypertension [170]. In this chiral pool approach, latanoprost acid (E10) is treated with 4-bromobutyl nitrate in the presence of K2CO3 and KI (Scheme 66) [171,172].

Scheme 66.

Scheme 66

Synthesis of Latanoprostene bunod.

3.5.4. Danoprevir (2018)

InterMune Inc. and Array Biopharma Inc. developed danoprevir for the treatment of non-cirrhotic genotype 1b chronic HCV infections [173]. Dialkylation of imine intermediate E12 with 2-butene-1,4-dibromide afforded racemic vinylcyclopropane E13, which upon enzymatic resolution with alcalase 2.4L resulted in the formation of desired enantiomer E14. E14 is the key chiral fragment in the synthesis of danoprevir (Scheme 67) [174].

Scheme 67.

Scheme 67

Synthesis of Danoprevir.

3.6. Drugs with More Than Five Chiral Centers

For drugs with more than five chiral centers, only the step in which chirality is induced is described in the scheme.

3.6.1. Velpatasvir (2016)

Velpatasvir, an antiviral drug developed by Gilead Sciences, is used, in combination with sofosbuvir, for the oral treatment of chronic HCV genotypes (1–6) [175]. The combination of chiral subunits in velpatasvir is shown in Scheme 68 [176]. Of all the chiral centers present in the drug, only the initial chiral induction by means of crystallization is highlighted. Commercially available glutamate (F1) undergoes intramolecular condensation to form dihydropyrrole (F2). The reduction of ester functionalities, followed by alkylation and crystallization, results in the cis form, F4.

Scheme 68.

Scheme 68

Synthesis of Velpatasvir.

3.6.2. Obeticholic Acid (2016)

Obeticholic acid, in combination with ursodeoxycholic acid, is used in the treatment of primary biliary cholangitis [177]. This drug was discovered at the Universita de Perugia and developed by Intercept Pharmaceuticals. In this chiral pool strategy, hydrogenation of the olefin intermediate F6, followed by heating to reflux, resulted in the epimerized fragment α-ethyl ketone F7 (Scheme 69) [178,179].

Scheme 69.

Scheme 69

Synthesis of Obeticholic acid.

3.6.3. Grazoprevir Hydrate (2016)

Merck discovered grazoprevir hydrate, a drug that, in combination with elbasvir, has been used to treat HCV infections. Similar to danoprevir, the key chiral subunit, F12, is formed by enzymatic resolution of the racemic cyclopropyl intermediate, F11. Commercially available boronate (F9) is converted to the cyclopropane derivative, F10, under Simmons–Smith conditions. Finally, the enantiomer is produced by resolution with a novozyme, followed by crystallization [180]. The remaining subunits are successively inserted in a step-by-step sequence (Scheme 70).

Scheme 70.

Scheme 70

Synthesis of Grazoprevir hydrate.

3.6.4. Ertugliflozin-l-pyroglutamic Acid (2017)

Ertugliflozin, discovered by Pfizer and co-developed by Pfizer and Merck, is used for the treatment of type II diabetes mellitus [181]. The synthesis of ertuglifozin commences from a chiral pool of glucose derivative F14 (Scheme 71) [182]. Oxidation, amidation, and treatment under Parikh–Doering conditions (SO3. Py) affords the chiral intermediate, F15. Oxalate salt (F18) formation occurs via a series of reactions, viz., pivalate group removal and protection of the hindered OH group.

Scheme 71.

Scheme 71

Synthesis of Ertugliflozin-l-pyroglutamic acid.

3.6.5. Voxilaprevir (2017)

Voxilaprevir, in combination with sofosbuvir and velpatasvir, is used to treat chronic HCV genotypes [183]. Gilead described the synthesis of voxilaprevir in nine steps from the pyrrolidinol derivative, F23. The enone formed by the reaction of pyrrolidinone (F20) with Grignard reagent, followed by hydrogenation, results in the addition of an ethyl group on the pyrrolidine ring (F21). Reduction, subjection to citric acid, and Boc protection introduce three stereocenters to the alcohol derivative, F23. Chiral centers are inserted in such a way that three are from the pyrrolidinol fragment (F20); three are from the cyclopropyl fragment, and two are from the cyclopropyl amine fragment (Scheme 72) [184].

Scheme 72.

Scheme 72

Synthesis of Voxilaprevir.

3.6.6. Pibrentasvir (2017)

Pibrentasvir, in combination with glecaprevir, was discovered and developed by Abbvie and Enanta Pharmaceuticals and is used for the treatment of chronic HCV genotypes (1–6) [185]. Pibrentasvir is formed via the union of different chiral subunits at various stages of synthesis. The very first stereogenic formation is initiated by the chiral diol fragment, F26, which was synthesized by asymmetric bis reduction in the presence of (R)-(+)-α,α-diphenyl-2-pyrrolidinemethanol by the Corey–Bakshi–Shibata (CBS) reduction mechanism (Scheme 73) [186].

Scheme 73.

Scheme 73

Synthesis of Pibrentasvir.

3.6.7. Glecaprevir (2017)

Glecaprevir was first discovered and developed by Abbvie and Enanta Pharmaceuticals. Glecaprevir, in combination with pibrentasvir, has been used to treat chronic HCV infections. Glecaprevir is an assembly of chiral fragments. Of these, one notable step is the resolution of the cyclopropane intermediate, F28, utilizing esterase as a resolving agent (Scheme 74) [187].

Scheme 74.

Scheme 74

Synthesis of Glecaprevir.

3.6.8. Segesterone Acetate (2018)

The Population Council developed segesterone acetate, a progestin hormonal contraceptive. The chiral pool substrate, 19-norandrostenedione (F31), is converted into an alcohol intermediate (F33) through the hydration of the alkyne derivative, F32. Inversion of the configuration is observed at C-17 (F34) via 2,3-sigmatropic rearrangement (Scheme 75) [188].

Scheme 75.

Scheme 75

Synthesis of Segesterone acetate.

3.6.9. Plitidepsin (2018)

Plitidepsin, a natural marine product, is a potent antiproliferative drug [189]. The combination of different subunits comprises the synthesis of plitidepsin in seven steps. The chiral fragment necessary for the synthesis of the drug is generated starting from the conversion of N-Boc isoleucine F36 to keto ester F37, followed by the sequential reduction, silylation, and deprotection of the ester to give plitidepsin carboxylic acid F38 in good yield (Scheme 76) [190].

Scheme 76.

Scheme 76

Synthesis of Plitidepsin.

3.6.10. Moxidectin (2018)

The Medicines Development for Global Health (MDGH) developed moxidectin. It is used for the treatment of onchocerciasis, also known as river blindness [191]. Moxidectin belongs to the milbemycin class comprised of 16-membered macrocyclic lactones. The chiral pool substrate nemadectin (F40), obtained by fermentation of Streptomyces cyanogriseus ssp. noncyanogenus, is converted to the ketone intermediate, F41, which then undergoes oxime formation and selective saponification of the ester-protecting group to afford moxidectin F42. It is worth mentioning that the oxime F42 retains (E)-configuration throughout the last two steps. (Scheme 77) [192].

Scheme 77.

Scheme 77

Synthesis of Moxidectin.

3.6.11. Plazomicin (2018)

Ionis Pharmaceuticals, Inc. discovered plazomicin, which was then further developed by Achaogen. It is used for the treatment of complicated urinary tract infections [193]. Unlike the chiral pool syntheses, commercially available and natural sisomicin commences the synthesis of plazomicin. The key intermediate F44 was synthesized by converting sisomicin to protected amine F43 in three step sequences and incorporation of Boc-(S)-HABA to amine (Scheme 78) [194,195,196,197,198,199].

Scheme 78.

Scheme 78

Synthesis of Intermediate of Plazomicin.

3.6.12. Tecovirimat (2018)

SIGA Technologies and the United States Department of Health Services Biomedical Advances Research and Development Authority developed tecovirimat [200]. Cycloaddition of cycloheptatriene (F46) and maleic anhydride (F47) delivers mixtures F48 and F49, which then undergo recrystallization with methyl tert-butyl ether (MTBE) to isolate the endo isomer, F49 (Scheme 79) [201].

Scheme 79.

Scheme 79

Synthesis of Tecovirimat.

3.6.13. Lefamulin (2019)

Nabriva Therapeutics developed lefamulin for the treatment of community-acquired bacterial pneumonia [202]. The total synthesis of lefamulin is performed in five steps, beginning with pleuromulin F51. The key subunit involved in the synthesis, F52, is obtained by the reaction with cyclohexanethiol in the presence of sodium hydroxide and benzyl(tributyl)ammonium chloride (BTBAC) in methyl tert-butyl ether (MTBE) (Scheme 80) [203].

Scheme 80.

Scheme 80

Synthesis of Lefamulin.

3.6.14. Afamelanotide (2019)

Afamelanotide was developed by Clinuvel Pharmaceuticals. It is used to treat erythropoietic protoporphyria [204]. Afamelanotide, with the amino acid sequence Ac-Ser-Tyl-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2, is synthesized in 31 steps from the commercially available resin, F54 (Scheme 81) [205,206].

Scheme 81.

Scheme 81

Synthesis of Afamelanotide.

3.6.15. Brexanolone (2019)

Sage Therapeutics developed brexanolone, which is used in the treatment of postpartum depression [207]. Pregnenolone (F56) initiates the linear synthesis of brexanolone (F57) in a sequential hydrogenation reduction and Mitsunobu reaction with diethylazodicarboxylate (DEAD) and triphenylphosphine (Scheme 82) [208].

Scheme 82.

Scheme 82

Synthesis of Brexanolone.

3.6.16. Bremelanotide (2019)

Bremelanotide is used in the treatment of hypoactive sexual desire disorder in premenopausal women [209]. Similar to afamelanotide, the synthesis begins with Rink-Amide-AM-resin (F58) and continues with the successful linkage of chiral amino acid derivatives, removal of N-Fmoc protecting group, and condensation with Fmoc-Trp(Boc)-OH (Scheme 83) [210].

Scheme 83.

Scheme 83

Synthesis of Bremelanotide.

3.6.17. Lurbinectedin (2020)

Lurbinectedin is used in the treatment of metastatic small-cell lung cancer in patients who have undergone platinum-based chemotherapy [211]. The total synthesis of lurbinectedin is carried out in 27 steps starting from the chiral pool l-tyrosine, F61 (Scheme 84) [212].

Scheme 84.

Scheme 84

Synthesis of Lurbinectedin.

3.6.18. Lactitol (2020)

Pizensy developed lactitol, a β-d-galactopyranosyl-d-glucitol. It is used to treat chronic idiopathic constipation [213]. The chiral pool synthesis of lactitol from lactose (F63) is achieved in a single step (Scheme 85) [214].

Scheme 85.

Scheme 85

Synthesis of Lactitol.

3.6.19. Setmelanotide (2020)

Chronic weight management can be treated with setmelanotide [215]. Setmelanotide is synthesized in ten steps with successive insertion of chiral centers, starting from commercially available arginine (F65) and phenyl alanine (F66) derivatives (Scheme 86) [216].

Scheme 86.

Scheme 86

Synthesis of Setmelanotide.

3.6.20. Clascoterone (2020)

Cassiopea developed clascoterone. It is widely used for the treatment of acne [217]. Hydrocortisone (F69) induces chirality in clascoterone in two steps (Scheme 87) [218].

Scheme 87.

Scheme 87

Synthesis of Clascoterone.

3.6.21. Artesunate (2020)

Arnivas developed artesunate for the treatment of severe malaria. The semi-synthesis of artesunate is accomplished using a chiral pool of artesimin (F72) isolated from Artemisia annua (Scheme 88) [219].

Scheme 88.

Scheme 88

Synthesis of Artesunate.

3.6.22. Remdesivir (2020)

Remdesivir was developed by Gilead Sciences [220]. It is used for the treatment of Ebola virus disease. The triazine intermediate, F75, generated from the hemiacetal derivative undergoes chiral SFC separation to form chiral fragment F76, which is essential for the development of remdesivir drugs (Scheme 89) [221].

Scheme 89.

Scheme 89

Synthesis of Remdesivir.

4. Conclusions

The concept of chirality has gained considerable attention owing to its importance in the field of medicinal chemistry. The importance of chirality is evidenced by the fact that most of the new drugs introduced annually into the market are single enantiomers. In general, drugs have structural homology across similar biological targets, and it is widely believed that knowledge of new chemical entities and approaches to their construction will enhance our ability to discover new drugs more efficiently. Incorporating chirality into drug discovery is a promising approach to better engage biological targets with enhanced drug properties. Chirality has the efficacy to remedy the challenges of drug optimization by exploiting the three-dimensional nature of biology. Moreover, chiral small molecules are upsurging as an attractive clinical advantage in drug discovery. Our quest to find the way by which chirality is induced led us to summarize the asymmetric synthesis of 89 FDA drugs approved from 2016 to 2020. The majority of the drugs were employed for the treatment of infectious diseases (28 drugs), oncology (20 drugs), metabolic and gastrointestinal disorders (14 drugs), central nervous system disorders (12 drugs), and others (15 drugs). With 89 new drugs approved by the FDA in hand, we extracted a subgroup of small molecules featuring one or more chiral centers, and analyzed their synthetic profile. The recent major progress in new asymmetric synthetic methodologies and enantiomeric separation techniques encourage the effort of chiral drug development. With regard to the methods routinely utilized to check the enantiomeric purity at the different stages of the discovery process, the term “chiral SFC” proved to emerge in the list of the synthesized drugs. Furthermore, we found out that all the drugs have been approved as single enantiomers with a well-defined absolute stereochemistry.

It has since become clear that the individual enantiomers can have vastly different effects on the body, leading to a shift toward the development of single enantiomers as drugs. This trend is driven by advances in analytical techniques that allow for the separation and characterization of individual enantiomers, as well as a growing understanding of the pharmacology of chiral compounds. Additionally, the increasing focus on personalized medicine and the development of targeted therapies has led to a greater appreciation of the importance of chirality in drug discovery and development. Chiral drugs are now a major area of research and development in the pharmaceutical industry, with many companies investing heavily in the discovery and development of new chiral drugs. In terms of the costs of drug substances, the asymmetric synthesis of chiral drugs is still expensive. So, technological advances in asymmetric synthesis and chiral resolution/separation are continuously required.

Author Contributions

Conceptualization, R.T. and D.S.; methodology, R.T. and D.S.; writing—original draft preparation, R.T.; writing—review and editing, R.T. and D.S. All authors have read and agreed to the published version of the manuscript.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

Funding Statement

This research was funded by the National Research Foundation of Korea (NRF-2020R1A6A1A3043708 and NRF-2021R1A2C1012280).

Footnotes

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References

  • 1.Blaser H.U. Industrial asymmetric hydrogenation. In: Crawley M.L., Trost B.M., editors. Applications of Transition Metal Catalysis in Drug Discovery and Development. Wiley; New York, NY, USA: 2012. pp. 315–342. [Google Scholar]
  • 2.Biot J.B. Phénomènes de polarisation successive, observés dans des fluides homogénes. Bull. Soc. Philomatique. 1815:190–192. [Google Scholar]
  • 3.Pasteur L. Recherches sur les propriétés spécifiques des deux acides qui composent pacide racémique. Ann. Chim. Phys. 1850;28:56–99. [Google Scholar]
  • 4.Morrow S.M., Bissette A.J., Fletcher S.P. Transmission of Chirality Through Space and Across Length Scales. Nat. Nanotechnol. 2017;12:410–419. doi: 10.1038/nnano.2017.62. [DOI] [PubMed] [Google Scholar]
  • 5.Nguyen L.A., He H., Pham-Huy C. Chiral drugs. An Overview. Int. J. Biomed. Sci. 2006;2:85–100. [PMC free article] [PubMed] [Google Scholar]
  • 6.Drayer D.E. Pharmacodynamic and Pharmacokinetic Differences Between Drug Enantiomers in Human: An Overview. Clin. Pharmacol. Ther. 1986;40:125–133. doi: 10.1038/clpt.1986.150. [DOI] [PubMed] [Google Scholar]
  • 7.James H.K., Anthony R.S. Thalidomide: The Tragedy of Birth Defects and the Effective Treatment of Disease. Toxicol. Sci. 2011;122:1–6. doi: 10.1093/toxsci/kfr088. [DOI] [PubMed] [Google Scholar]
  • 8.Yu T.L., Chan Y., Yan W., Jun J.L., Xiao F., Xiaofei T., Zhengzheng Z., Xiaoyan P., Shuwen L., Li W.T. Axial Chiral Binaphthoquinone and Perylenequinones from the Stromata of Hypocrella bambusae Are SARS-CoV-2 Entry Inhibitors. J. Nat. Prod. 2021;84:436–443. doi: 10.1021/acs.jnatprod.0c01136. [DOI] [PubMed] [Google Scholar]
  • 9.Zhonglei W. Advances in the Asymmetric Total Synthesis of Natural Products Using Chiral Secondary Amine Catalyzed Reactions of α,β-Unsaturated Aldehydes. Molecules. 2019;24:3412–3449. doi: 10.3390/molecules24183412. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10.Reilly E.S., Donald M.C., Justin L.N. Chiral Analysis of Linalool, an Important Natural Fragrance and Flavor Compound, by Molecular Rotational Resonance Spectroscopy. Symmetry. 2022;14:917–926. [Google Scholar]
  • 11.US FDA FDA’s Policy Statement for the Development of New Stereoisomeric Drugs. FDA Website [Online] [(accessed on 1 May 1992)]; Available online: http://www.fda.gov/drugs/GuidanceComplianceRegulatoryInformation/Guidances/ucm122883.htm.
  • 12.Singh M., Sethi S., Bhushan R. Liquid chromatographic methods for separation, determination, and bioassay of enantiomers of etodolac: A review. J. Sep. Sci. 2019;43:18–30. doi: 10.1002/jssc.201900649. [DOI] [PubMed] [Google Scholar]
  • 13.Patocka J., Dvorak A. Biomedical Aspects of Chiral Molecules. J. Appl. Med. 2004;2:95–100. doi: 10.32725/jab.2004.011. [DOI] [Google Scholar]
  • 14.Coelho M.M., Fernandes C., Remião F., Tiritan M.E. Enantioselectivity in drug pharmacokinetics and toxicity: Pharmacological relevance and analytical methods. Molecules. 2021;26:3113. doi: 10.3390/molecules26113113. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15.Jarvis L.M. FDA gives its nod to 53 new drugs in 2020. [(accessed on 5 August 2022)];Chem. Eng. News. 2021 99 Available online: https://cen.acs.org/pharmaceuticals/drug-development/FDA-gives-nod-53-new/99/i2. [Google Scholar]
  • 16. [(accessed on 12 August 2017)]. Available online: https://www.shire.com/newsroom/2016/july/9pks5v.
  • 17.Abidi A., Shukla P., Ahmad A. Lifitegrast: A Novel Drug for Treatment of Dry Eye Disease. J. Pharmacol. Pharmacother. 2016;7:194–198. doi: 10.4103/0976-500X.195920. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 18.Zeller J.R., Venkatraman S., Brot E.C.A., Iyer S., Hall M. LFA-1 Inhibitor and Polymorph Thereof. WO 2014018748A1. 2014 January 30;
  • 19.Markham A., Dhillon S. Acalabrutinib: First Global Approval. Drugs. 2018;78:139–145. doi: 10.1007/s40265-017-0852-8. [DOI] [PubMed] [Google Scholar]
  • 20.Mo G., Zha X. Preparation of Btk Inhibitor Acalabrutinib. CN 107522701A. 2019 November 8;
  • 21.Xu X. Process for the Preparation of Acalabrutinib. CN 107056786A. 2018 October 25;
  • 22.Blair H.A. Pemafibrate: First Global Approval. Drugs. 2017;77:1805–1810. doi: 10.1007/s40265-017-0818-x. [DOI] [PubMed] [Google Scholar]
  • 23.Yamazaki Y., Araki T., Koura M., Shibuya K. A Practical Synthesis of the PPARα Agonist, (R)-K-13675, Starting from (S)-2-Hydroxybutyrolactone. Tetrahedron. 2008;64:8155–8158. doi: 10.1016/j.tet.2008.06.049. [DOI] [Google Scholar]
  • 24.Kim E.S. Letermovir: First Global Approval. Drugs. 2018;78:147–152. doi: 10.1007/s40265-017-0860-8. [DOI] [PubMed] [Google Scholar]
  • 25.Humphrey G.R., Dalby S.M., Andreani T., Xiang B., Luzung M.R., Song Z.J., Shevlin M., Christensen M., Belyk K.M., Tschaen D.M. Asymmetric Synthesis of Letermovir Using a Novel Phase-Transfer-Catalyzed Aza-Michael Reaction. Org. Process Res. Dev. 2016;20:1097–1103. doi: 10.1021/acs.oprd.6b00076. [DOI] [Google Scholar]
  • 26.Hoy S.M. Netarsudil Ophthalmic Solution 0.02%: First Global Approval. Drugs. 2018;78:389–396. doi: 10.1007/s40265-018-0877-7. [DOI] [PubMed] [Google Scholar]
  • 27.Sturdivant J.M., Delong M.A., Chambournier G., Pamment M.G., Fedij V. Process for the Preparation of Kinase Inhibitors and Intermediates Thereof. WO 2017086941A1. 2017 May 26;
  • 28.TESARO Announces, U.S. FDA Approval of ZEJULA (Niraparib) for Women with Recurrent Ovarian Cancer; TESARO, March 27, 2017. [(accessed on 19 November 2018)]. Available online: http://ir.tesarobio.com/news-releases/news-releasedetails/tesaro-announces-us-fda-approval-zejulatm-niraparib-women.
  • 29.Chung C.K., Bulger P.G., Kosjek B., Belyk K.M., Rivera N., Scott M.E., Humphrey G.R., Limanto J., Bachert D.C., Emerson K.M. Process Development of C−N Cross-Coupling and Enantioselective Biocatalytic Reactions for the Asymmetric Synthesis of Niraparib. Org. Process Res. Dev. 2014;18:215–227. doi: 10.1021/op400233z. [DOI] [Google Scholar]
  • 30.Hughes D.L. Patent Review of Manufacturing Routes to Recently Approved PARP. Inhibitors: Olaparib, Rucaparib and Niraparib. Org. Process Res. Dev. 2017;21:1227–1244. doi: 10.1021/acs.oprd.7b00235. [DOI] [Google Scholar]
  • 31.Chung C.K., Scott M.E., Bulger P.G., Belyk K.M., Limanto J., Humphrey G.R. Regioselective N-2 Arylation of Indazoles. WO 2014088983A1. 2014 June 12;
  • 32.Bulger P.G., Kosjek B., Rivera N. Biocatalytic Transamination Process. US. 20160040201A1. 2017 August 22;
  • 33.Syed Y.Y. Lorlatinib: First Global Approval. Drugs. 2019;79:93–98. doi: 10.1007/s40265-018-1041-0. [DOI] [PubMed] [Google Scholar]
  • 34.Duan S., Li B., Dugger R.W., Conway B., Kumar R., Martinez C., Makowski T., Pearson R., Olivier M., Colon-Cruz R. Developing an Asymmetric Transfer Hydrogenation Process for (S)-5-Fluoro-3-Methylisobenzofuran-1(3h)-One, a Key Intermediate to Lorlatinib. Org. Process Res. Dev. 2017;21:1340–1348. doi: 10.1021/acs.oprd.7b00187. [DOI] [Google Scholar]
  • 35.Chedid V., Vijayvargiya P., Camilleri M. Elobixibat for the Treatment of Constipation. Expert Rev. Gastroenterol. Hepatol. 2018;12:951–960. doi: 10.1080/17474124.2018.1522248. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 36.Starke I., Dahlstrom M.U.J., Blomberg D., Alenfalk S., Nordberg P., Wallberg A.C., Bostrom S.J. Preparation of Benzothiazepine Derivatives for Potential Use as Ileal Bile Acid Transport Inhibitors for the Treatment of Hyperlipidemia. WO2003020710A1. 2003 March 13;
  • 37.Donaldson S.H., Pilewski J.M., Griese M., Cooke J., Viswanathan L., Tullis E., Davies J.C., Lekstrom-Himes J.A., Wang L.T. Tezacaftor/Ivacaftor in Subjects with Cystic Fibrosis and F508del/F508del-CFTR or F508del/G551D-CFTR. Am. J. Respir. Crit. Care Med. 2018;197:214–224. doi: 10.1164/rccm.201704-0717OC. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 38.Taylor-Cousar J.L., Munck A., McKone E.F., van der Ent C.K., Moeller A., Simard C., Wang L.T., Ingenito E.P., McKee C., Lu Y., et al. Tezacaftor-Ivacaftor in Patients with Cystic Fibrosis Homozygous for Phe508del. N. Engl. J. Med. 2017;377:2013–2023. doi: 10.1056/NEJMoa1709846. [DOI] [PubMed] [Google Scholar]
  • 39.Phenix B.D., Bagnol L.J.-C., Brodeur G.G., Chandran S., Dokou E., Ferris L.A., Knezic D., McCarty K.L., Medek A., Waggener S.A. Method for Preparation of Quinolinone Carboxamides, Indole Carboxamides and Pharmaceutical Compositions Containing Them for the Treatment of Cystic Fibrosis Transmembrane Conductance Regulator Mediated Diseases. WO2015160787A1. 2015 October 22;
  • 40.Blair H.A. Pyrotinib: First Global Approval. Drugs. 2018;78:1751–1755. doi: 10.1007/s40265-018-0997-0. [DOI] [PubMed] [Google Scholar]
  • 41.Wu G., Zhang Q., Cao Y. Method for Preparing Tyrosine Kinase Inhibitor and Derivative Thereof. WO2017186140A1. 2021 December 15;
  • 42.Shirley M. Encorafenib and Binimetinib: First Global Approvals. Drugs. 2018;78:1277–1284. doi: 10.1007/s40265-018-0963-x. [DOI] [PubMed] [Google Scholar]
  • 43.Huang S., Jin X., Liu Z., Poon D., Tellew J., Wan Y., Wang X., Xie Y. Compounds and Compositions as Protein Kinase Inhibitors. WO2011025927A1. 2021 December 15;
  • 44.Anastasia A., Rossi G. Novel Drugs in Follicular Lymphoma. Mediterr. J. Hematol. Infect. Dis. 2015;8:e2016061. doi: 10.4084/MJHID.2016.061. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 45.Rodrigues D.A., Sagrillo F.S., Fraga C.A.M. Duvelisib: A 2018 Novel FDA-Approved Small Molecule Inhibiting Phosphoinositide 3-Kinases. Pharmaceuticals. 2019;12:69. doi: 10.3390/ph12020069. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 46.Vangapandu H.V., Jain N., Gandhi V. Duvelisib: A Phosphoinositide-3 Kinase Delta/Gamma Inhibitor for Chronic Lymphocytic Leukemia. Expert Opin. Investig. Drugs. 2017;26:625–632. doi: 10.1080/13543784.2017.1312338. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 47.Ren P., Martin M., Isbester P., Lane B., Kropp J. Process for Preparing Isoquinolines and Solid Forms of Isoquinolines. WO2012097000A1. 2021 December 15;
  • 48.Lamb Y.N. Elagolix: First Global Approval. Drugs. 2018;78:1501–1508. doi: 10.1007/s40265-018-0977-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 49.Chen C., Wu D., Guo Z., Xie Q., Reinhart G.J., Madan A., Wen J., Chen T., Huang C.Q., Chen M., et al. Discovery of Sodium R-(+)-4-{2-[5-(2- Fluoro-3-Methoxyphenyl)-3-(2-Fluoro-6-[Trifluoromethyl]Benzyl)-4- Methyl-2,6-Dioxo-3,6-Dihyd ro-2h-Pyrimidin-1-Yl]-1- Phenylethylamino}Butyrate (Elagolix), a Potent and Orally Available Nonpeptide Antagonist of the Human Gonadotropin-Releasing Hormone Receptor. J. Med. Chem. 2008;51:7478–7485. doi: 10.1021/jm8006454. [DOI] [PubMed] [Google Scholar]
  • 50.Takahashi N., Take Y. Tegoprazan, a Novel PotassiumCompetitive Acid Blocker to Control Gastric Acid Secretion and Motility. J. Pharmacol. Exp. Ther. 2018;364:275–286. doi: 10.1124/jpet.117.244202. [DOI] [PubMed] [Google Scholar]
  • 51.Xiaolong Q., Lin H., Wenbo L., Ping Z., Lingling C., Xingang Z., Ping W., Donghui W., Lei C., Jun C. Method for Synthetizing Tegoprazan Chiral Alcohol. CN109320485. 2021 May 28;
  • 52.Stirrups R. Alpelisib Plus Fulvestrant for PIK3CA-Mutated Breast Cancer. Lancet Oncol. 2019;20:347. doi: 10.1016/S1470-2045(19)30372-9. [DOI] [PubMed] [Google Scholar]
  • 53.Andre F., Ciruelos E., Rubovszky G., Campone M., Loibl S., Rugo H.S., Iwata H., Conte P., Mayer I.A., Kaufman B., et al. Alpelisib for PIK3CA-Mutated, Hormone Receptor-Positive Advanced Breast Cancer. N. Engl. J. Med. 2019;380:1929–1940. doi: 10.1056/NEJMoa1813904. [DOI] [PubMed] [Google Scholar]
  • 54.Caravatti R.A., Fairhurst P., Furet V., Guagnano P. Imbach, Thiazole Derivatives Used as PI3 Kinase Inhibitors. WO2009080694. 2009 July 2;
  • 55.Strollo P.J., Hedner J., Collop N., Lorch D.G., Chen D., Carter L.P., Lu Y., Lee L., Black J., Pepin J.L., et al. Solriamfetol for the Treatment of Excessive Sleepiness in OSA: A Placebo-Controlled Randomized Withdrawal Study. Chest. 2019;155:364–374. doi: 10.1016/j.chest.2018.11.005. [DOI] [PubMed] [Google Scholar]
  • 56.Markham A. Solriamfetol: First Global Approval. Drugs. 2019;79:785–790. doi: 10.1007/s40265-019-01123-y. [DOI] [PubMed] [Google Scholar]
  • 57.Choi Y.M., Kim M.W. Process of Preparing O-Carbamoyl Compounds in the Presence of Active Amine Group. WO2005033064. 2005 April 14;
  • 58.Wang X., Inoyama D., Russo R., Li S.G., Jadhav R., Stratton T.P., Mittal N., Bilotta J.A., Singleton E., Kim T., et al. Antitubercular Triazines: Optimization and Intrabacterial Metabolism. Cell Chem. Biol. 2020;27:172–185. doi: 10.1016/j.chembiol.2019.10.010. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 59.Miao D., Hu Q., Li Y., Yu Z., Wang H., Zhu X. Synthesis Method of PA-824 (Pretomanid) for Treating Tuberculosis. CN107915747. 2020 November 10;
  • 60.Tam C.S., Trotman J., Opat S., Burger J.A., Cull G., Gottlieb D., Harrup R., Johnston P.B., Marlton P., Munoz J., et al. Phase 1 Study of the Selective BTK Inhibitor Zanubrutinib in Bcell Malignancies and Safety and Efficacy Evaluation in CLL. Blood. 2019;134:851–859. doi: 10.1182/blood.2019001160. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 61.Guo Y., Wang Z. Fused Heterocyclic Compounds as Protein Kinase Inhibitors. WO2014173289. 2014 October 30;
  • 62.Markham A., Duggan S. Darolutamide: First Approval. Drugs. 2019;79:1813–1818. doi: 10.1007/s40265-019-01212-y. [DOI] [PubMed] [Google Scholar]
  • 63.Fizazi K., Shore N., Tammela T.L., Ulys A., Vjaters E., Polyakov S., Jievaltas M., Luz M., Alekseev B., Kuss I., et al. Darolutamide in Nonmetastatic, Castration-Resistant Prostate Cancer. N. Engl. J. Med. 2019;380:1235–1246. doi: 10.1056/NEJMoa1815671. [DOI] [PubMed] [Google Scholar]
  • 64.Laitinen I., Karjalainen O. Process for the Preparation of Androgen Receptor Antagonists and Intermediates Thereof. WO2016162604. 2016 October 13;
  • 65.Pan T., Xia C., Yang Y., Zhang A. Process and Intermediates for Preparation of Androgen Receptor Antagonist. CN108218908. 2018 June 29;
  • 66.Tormakangas O., Wohlfahrt G., Salo H., Ramasubramanian R.D., Patra P.K., Martin A.E., Heikkinen T., Vesalainen A., Moilanen A., Karjalainen A. Androgen Receptor Modulating Carboxamides. WO2012143599. 2012 October 26;
  • 67.Kasteleijn-Nolst Trenite D.G.A., DiVentura B.D., Pollard J.R., Krauss G.L., Mizne S., French J.A. Suppression of the Photoparoxysmal Response in Photosensitive Epilepsy with Cenobamate (YKP3089) Neurology. 2019;93:559–567. doi: 10.1212/WNL.0000000000007894. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 68.Choi Y.M., Kim C.G., Kang Y.S., Yi H.J., Lee H.S., Ku B.C., Lee E.H., Im D.J., Shin Y.J. Preparation of Triazoles and Tetrazoles Containing Carbamoyl Group as Anticonvulsants. WO2006112685. 2006 October 26;
  • 69.Dhillon S. Avapritinib: First Approval. Drugs. 2020;80:433–439. doi: 10.1007/s40265-020-01275-2. [DOI] [PubMed] [Google Scholar]
  • 70.Zhang Y., Hodous B.L., Kim J.L., Wilson K.J., Wilson D. Compositions Useful for Treating Disorders Related to KIT. WO2015057873. 2015 April 23;
  • 71.Ohsawa I., Honda D., Suzuki Y., Fukuda T., Kohga K., Morita E., Moriwaki S., Ishikawa O., Sasaki Y., Tago M., et al. Oral Berotralstat for the Prophylaxis of Hereditary Angioedema Attacks in Patients in Japan: A Phase 3 Randomized Trial. Allergy. 2021;76:1789–1799. doi: 10.1111/all.14670. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 72.El-Kattan Y., Babu Y.S. Crystalline Salts of a Plasma Kallikrein Inhibitor. US20200140389. 2020 May 26;
  • 73.Gordon L.B., Kleinman M.E., Massaro J., D’Agostino R.B., Shappell S.H., Gerhard-Herman M., Smoot L.B., Gordon C.M., Cleveland R.H., Nazarian A., et al. Clinical Trial of the Protein Farnesylation Inhibitors Lonafarnib, Pravastatin, and Zoledronic Acid in Children with Hutchinson-Gilford Progeria Syndrome. Circulation. 2016;134:114–125. doi: 10.1161/CIRCULATIONAHA.116.022188. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 74.Njoroge F.G., Vibulbhan B., Rane D.F., Bishop W.R., Petrin J., Patton R., Bryant M.S., Chen K.J., Nomeir A.A., Lin C.C., et al. Structure-Activity Relationship of 3- Substituted N-(Pyridinylacetyl)-4-(8-Chloro-5,6-dihydro-11H-benzo[5,6] Cyclohepta[1,2-b]Pyridin-11-ylidene)Piperidine Inhibitors of Farnesylprotein Transferase: Design and Synthesis of in vivo Active Antitumor Compounds. J. Med. Chem. 1997;40:4290–4301. doi: 10.1021/jm970464g. [DOI] [PubMed] [Google Scholar]
  • 75.Duggan S. Osilodrostat: First Approval. Drugs. 2020;80:495–500. doi: 10.1007/s40265-020-01277-0. [DOI] [PubMed] [Google Scholar]
  • 76.Zhang C., Chakma J. 3-Fluoro-Benzonitrile Inhibitors of 11-Beta-Hydroxylase. WO2016109361. 2016 July 7;
  • 77.Markham A. Oliceridine: First Approval. Drugs. 2020;80:1739–1744. doi: 10.1007/s40265-020-01414-9. [DOI] [PubMed] [Google Scholar]
  • 78.Yamashita D., Gotchev D., Pitis P., Chen X.T., Liu G., Yuan C.C.K. Opioid Receptor Ligands and Methods of Using and Making Same. WO2012129495. 2012 September 27;
  • 79.Sneyd J.R., Rigby-Jones A.E. Remimazolam for Anaesthesia or Sedation. Curr. Opin. Anaesthesiol. 2020;33:506–511. doi: 10.1097/ACO.0000000000000877. [DOI] [PubMed] [Google Scholar]
  • 80.Feldman P.L., Jung D.K., Kaldor I., Pacofsky G.J., Stafford J.A., Tidwell J.H. Short-Acting Benzodiazepines. WO2000069836. 2000 November 23;
  • 81.Lamb Y.N. Ozanimod: First Approval. Drugs. 2020;80:841–848. doi: 10.1007/s40265-020-01319-7. [DOI] [PubMed] [Google Scholar]
  • 82.Martinborough E., Boehm M.F., Yeager A.R., Tamiya J., Huang L., Brahmachary E., Moorjani M., Timony G.A., Brooks J.L., Peach R., et al. Selective Sphingosine 1 Phosphate Receptor Modulators and Combination Therapy Therewith. WO2015066515. 2015 May 7;
  • 83.Poole R.M. Nemonoxacin: First Global Approval. Drugs. 2014;74:1445–1453. doi: 10.1007/s40265-014-0270-0. [DOI] [PubMed] [Google Scholar]
  • 84.Redman-Furey N.L., Godlewski J.E., Dicks M.L. Malate Salts, and Polymorphs of (3S,5S)-7-[3-Amino-5-Methyl-Piperidinyl]-1-Cyclopropyl-1,4-Dihydro-8-Methoxy-4-oxo-3-Quinolinecarboxylic Acid. US 8039485B2. 2011 October 18;
  • 85.Markham A. Brivaracetam: First Global Approval. Drugs. 2016;76:517–522. doi: 10.1007/s40265-016-0555-6. [DOI] [PubMed] [Google Scholar]
  • 86.Strzelczyk A., Klein K.M., Willems L.M., Rosenow F., Bauer S. Brivaracetam in the Treatment of Focal and Idiopathic Generalized Epilepsies and of Status Epilepticus. Expert Rev. Clin. Pharmacol. 2016;9:637–645. doi: 10.1586/17512433.2016.1156529. [DOI] [PubMed] [Google Scholar]
  • 87.Schüle A., Merschaert A., Szczepaniak C., Marechal C., Carly N., O’Rourke J., Ates C. A Biocatalytic Route to the Novel Antiepileptic Drug Brivaracetam. Org. Process Res. Dev. 2016;20:1566–1575. doi: 10.1021/acs.oprd.6b00094. [DOI] [Google Scholar]
  • 88.Gentles R.G., Ding M., Bender J.A., Bergstrom C.P., Grant-Young K., Hewawasam P., Hudyma T., Martin S., Nickel A., Regueiro-Ren A., et al. Discovery and Preclinical Characterization of the Cyclopropylindolobenzazepine BMS-791325, A Potent Allosteric Inhibitor of the Hepatitis C Virus NS5B Polymerase. J. Med. Chem. 2014;57:1855–1879. doi: 10.1021/jm4016894. [DOI] [PubMed] [Google Scholar]
  • 89.Bender J.A., Ding M., Gentles R.G., Hewawasam P. Preparation of Cyclopropyl Fused Indolobenzazepine Derivatives as Hepatitis C Virus (HCV) NS5B Polymerase Inhibitors. WO 20070270405. 2008 November 25;
  • 90.Jabbour E.J., DeAngelo D.J., Stelljes M., Stock W., Liedtke M., Goekbuget N., O’Brien S., Wang T., Paccagnella M.L., Sleight B., et al. Efficacy and Safety Analysis by Age Cohort of Inotuzumab Ozogamicin in Patients with Relapsed or Refractory Acute Lymphoblastic Leukemia Enrolled in Ino-Vate. Cancer. 2018;124:1722–1732. doi: 10.1002/cncr.31249. [DOI] [PubMed] [Google Scholar]
  • 91.Maiese W.M., Lechevalier M.P., Lechevalier H.A., Korshalla J., Kuck N., Fantini A., Wildey M.J., Thomas J., Greenstein M. Calicheamicins, a Novel Family of Antitumor Antibiotics: Taxonomy, Fermentation and Biological Properties. J. Antibiot. 1989;42:558–563. doi: 10.7164/antibiotics.42.558. [DOI] [PubMed] [Google Scholar]
  • 92.Lee M.D., Greenstein M., Labeda D.P., Fantini A.A. Fermentative Manufacture of Antitumor Antibiotics (Ll-E33288 Complex) US 4970198. 1990 November 13;
  • 93.Dugger R.W., Letendre L.J., Patel V.B., Prashad A.S., Zhang C. Intermediates and Methods for Synthesizing Calicheamicin Derivatives. WO 2015063680. 2015 May 7;
  • 94.Heo Y.A., Scott L.J. Deutetrabenazine: A Review in Chorea Associated with Huntington’s Disease. Drugs. 2017;77:1857–1864. doi: 10.1007/s40265-017-0831-0. [DOI] [PubMed] [Google Scholar]
  • 95.Zhang C. Methods of Manufacturing Benzoquinoline Compounds as Inhibitors of Vesicular Monoamine Transporter 2 (Vmat2) US 20150152099A1. 2019 December 24;
  • 96.Avery L.M., Nicolau D.P. Investigational Drugs for the Treatment of Infections Caused by Multidrug-Resistant Gram-Negative Bacteria. Expert Opin. Investig. Drugs. 2018;27:325–338. doi: 10.1080/13543784.2018.1460354. [DOI] [PubMed] [Google Scholar]
  • 97.Hecker S.J., Reddy K.R., Totrov M., Hirst G.C., Lomovskaya O., Griffith D.C., King P., Tsivkovski R., Sun D., Sabet M., et al. Discovery of a Cyclic Boronic Acid B-Lactamase Inhibitor (Rpx7009) with Utility Vs Class a Serine Carbapenemases. J. Med. Chem. 2015;58:3682–3692. doi: 10.1021/acs.jmedchem.5b00127. [DOI] [PubMed] [Google Scholar]
  • 98.Markham A. Telotristat Ethyl: First Global Approval. Drugs. 2017;77:793–798. doi: 10.1007/s40265-017-0737-x. [DOI] [PubMed] [Google Scholar]
  • 99.Bednarz M.S., Burgoon H.A., Jr., Iimura S., Kanamarlapudi R.C., Song Q., Wu W., Yan J., Zhang H. Methods of Preparing 4-Phenyl-6-(2,2,2-trifluoro-1-phenylethoxy)pyrimidineBased Compounds. WO 2009029499A1. 2009 March 5;
  • 100.Bednarz M.S., De Paul S., Kanamarlapudi R.C., Perlberg A., Zhang H. Preparation of Solids Forms of (S)-Ethyl 2-Amino-3-(4-(2-amino-6-((R)-1-(4-chloro-2-(3-methyl-1H-pyrazol-1-yl)phenyl)-2,2,2-trifluoroethoxy)pyrimidin-4-yl)phenyl)propanoate. WO 2009042733A1. 2009 April 2;
  • 101.Scott L.J. Larotrectinib: First Global Approval. Drugs. 2019;79:201–206. doi: 10.1007/s40265-018-1044-x. [DOI] [PubMed] [Google Scholar]
  • 102.Reynolds M., Eary C.T., Spencer S., Juengst D., Hache B., Jiang Y., Haas J., Andrews S.W. Preparation of (S)-N-(5-((R)-2-(2,5-Difluorophenyl)pyrrolidin-1-yl)pyrazolo[1,5-a]pyrimidin-3-yl)-3-hydroxypyrrolidine-1-carboxamide. WO2017201241A1. 2017 November 23;
  • 103.Hoy S.M. Glasdegib: First Global Approval. Drugs. 2019;79:207–213. doi: 10.1007/s40265-018-1047-7. [DOI] [PubMed] [Google Scholar]
  • 104.Peng Z., Wong J.W., Hansen E.C., Puchlopek-Dermenci A.L.A., Clarke H.J. Development of a Concise, Asymmetric Synthesis of a Smoothened Receptor (SMO) Inhibitor: Enzymatic Transamination of a 4-Piperidinone with Dynamic Kinetic Resolution. Org. Lett. 2014;16:860–863. doi: 10.1021/ol403630g. [DOI] [PubMed] [Google Scholar]
  • 105.Hoy S.M. Talazoparib: First Global Approval. Drugs. 2018;78:1939–1946. doi: 10.1007/s40265-018-1026-z. [DOI] [PubMed] [Google Scholar]
  • 106.Wang B., Chu D., Liu Y., Jiang Q., Lu L. Processes of Synthesizing Dihydropyridophthalazinone Derivatives. WO2011097602A1. 2011 August 11;
  • 107.Wang B., Chu D., Liu Y., Peng S. Crystalline (8s,9r)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1h-1,2,4- triazol-5-yl)-8,9-dihydro-2h-pyrido[4,3,2-de]phthalazin-3(7h)-one Tosylate Salt. WO2012054698A1. 2014 August 14;
  • 108.Feng Y., Gutierrez A.A., Shen Y., Wang E.W., Okhamafe A.O., Price C.P., Chou T. Dihydropyridophthalazinone Inhibitors of Poly (Adp-Ribose) Polymerase (Parp) for the Treatment of Multiple Myeloma. WO2013028495A1. 2013 February 28;
  • 109.Dhillon S. Ivosidenib: First Global Approval. Drugs. 2018;78:1509–1516. doi: 10.1007/s40265-018-0978-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 110.Muthusamy A.R., Singh A., Yazali V.S., Luthra P.K., Vasoya S.L., Patil B.T., Taneja A.K., Srivastav N.C., Singh R., Rengasamy V., et al. Solid State Forms of Ivosidenib. WO2019104318A1. 2019 May 31;
  • 111.Miyazaki H., Ikeda Y., Sakurai O., Miyake T., Tsubota R., Okabe J., Kuroda M., Hisada Y., Yanagida T., Yoneda H., et al. Discovery of Evocalcet, a Next-Generation Calcium-Sensing Receptor Agonist for the Treatment of Hyperparathyroidism. Bioorg. Med. Chem. Lett. 2018;28:2055–2060. doi: 10.1016/j.bmcl.2018.04.055. [DOI] [PubMed] [Google Scholar]
  • 112.Heo Y.-A. Baloxavir: First Global Approval. Drugs. 2018;78:693–697. doi: 10.1007/s40265-018-0899-1. [DOI] [PubMed] [Google Scholar]
  • 113.Shibahara S., Fukui N., Maki T., Anan K. Method for Producing Substituted Polycyclic Pyridone Derivative and Crystal of Same. WO2017221869A1. 2017 December 28;
  • 114.Hata K., Kimura J., Miki H., Toyosawa T., Nakamura T., Katsu K. In Vitro and in Vivo Antifungal Activities of ER-30346, a Novel Oral Triazole with a Broad Antifungal Spectrum. Antimicrob. Agents Chemother. 1996;40:2237–2242. doi: 10.1128/AAC.40.10.2237. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 115.Pesti J., Chen C.-K., Spangler L., DelMonte A.J., Benoit S., Berglund D., Bien J., Brodfuehrer P., Chan Y., Corbett E., et al. The Process Development of Ravuconazole: An Efficient Multikilogram Scale Preparation of an Antifungal Agent. Org. Process Res. Dev. 2009;13:716–728. doi: 10.1021/op900065c. [DOI] [Google Scholar]
  • 116.Gao Q., Chen C.-P.H., Fakes M.G., Pendri Y.R., Kiau S., Vakkalagadda B. Preparation of Mono-Lysine Salts of Azole Compounds as Fungicides. WO2006118351A1. 2006 November 9;
  • 117.Vanover K.E., Davis R.E., Zhou Y., Ye W., Brasic J.R., Gapasin L., Saillard J., Weingart M., Litman R.E., Mates S., et al. Dopamine D2 Receptor Occupancy of Lumateperone (ITI-007): A Positron Emission Tomography Study in Patients with Schizophrenia. Neuropsychopharmacology. 2019;44:598–605. doi: 10.1038/s41386-018-0251-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 118.Li P., Zhang Q., Robichaud A.J., Lee T., Tomesch J., Yao W., Beard J.D., Snyder G.L., Zhu H., Peng Y., et al. Discovery of a Tetracyclic Quinoxaline Derivative as a Potent and orally active multifunctional drug candidate for the treatment of neuropsychiatric and neurological disorders. J. Med. Chem. 2014;57:2670–2682. doi: 10.1021/jm401958n. [DOI] [PubMed] [Google Scholar]
  • 119.Markham A. Tenapanor: First Approval. Drugs. 2019;79:1897–1903. doi: 10.1007/s40265-019-01215-9. [DOI] [PubMed] [Google Scholar]
  • 120.Richter J., Dammer O., Krejcik L., Hejtmankova L., Lustig P., Dousa M. Solid Forms of Tenapanor and Method of Preparation of Tenapanor. WO2019091503. 2019 May 16;
  • 121.Beuckmann C.T., Suzuki M., Ueno T., Nagaoka K., Arai T., Higashiyama H. In vitro and in Silico Characterization of Lemborexant (E2006), A Novel Dual Orexin Receptor Antagonist. J. Pharmacol. Exp. Ther. 2017;362:287–295. doi: 10.1124/jpet.117.241422. [DOI] [PubMed] [Google Scholar]
  • 122.Yoshida Y., Naoe Y., Terauchi T., Ozaki F., Doko T., Takemura A., Tanaka T., Sorimachi K., Beuckmann C.T., Suzuki M., et al. Discovery of (1R,2S)-2-{[(2,4-dimethylpyrimidin-5-yl)oxy]methyl}-2-(3- fluorophenyl)-N-(5-fluoropyridin-2-yl)cyclopropanecarboxamide (E2006): A Potent and Efficacious Oral Orexin Receptor Antagonist. J. Med. Chem. 2015;58:4648–4664. doi: 10.1021/acs.jmedchem.5b00217. [DOI] [PubMed] [Google Scholar]
  • 123.Sato T., Yamawaki K. Cefiderocol: Discovery, Chemistry, and in vivo Profiles of a Novel Siderophore Cephalosporin. Clin. Infect. Dis. 2019;69:538–543. doi: 10.1093/cid/ciz826. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 124.Yasuhiro N., Kenji Y., Yusuke T., Hideki S., Shinya H., Toshiaki A. Cephalosporin Having Catechol Group. AU2009310959. 2015 May 7;
  • 125.Duggan S., Keam S.J. Upadacitinib: First Approval. Drugs. 2019;79:1819–1828. doi: 10.1007/s40265-019-01211-z. [DOI] [PubMed] [Google Scholar]
  • 126.Wishart N., Argiriadi M.A., Calderwood D.J., Ericsson A.M., Fiamengo B.R., Frank K.E., Friedman M., George D.M., Goedken E.R., Josephsohn N.S., et al. Novel Tricyclic Compounds. US20110311474. 2013 April 23;
  • 127.Scott L.J., Chan H.L.Y. Tenofovir Alafenamide: A Review in Chronic Hepatitis B. Drugs. 2017;77:1017–1028. doi: 10.1007/s40265-017-0754-9. [DOI] [PubMed] [Google Scholar]
  • 128.Indukuri V.S.K., Joga S.R., Gorantla S.R., Chava S. Process for the Preparation of Tenofovir. US 20140303368, 16-06-2015. US 20140303368. 2015 June 16;
  • 129.Tsiang M., Jones G.S., Goldsmith J., Mulato A., Hansen D., Kan E., Tsai L., Bam R.A., Stepan G., Stray K.M., et al. Antiviral Activity of Bictegravir (GS-9883), a Novel Potent HIV-1 Integrase Strand Transfer Inhibitor with an Improved Resistance Profile. Antimicrob. Agents Chemother. 2016;60:7086–7097. doi: 10.1128/AAC.01474-16. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 130.Chiu A., Enquist J., Griggs N., Hale C., Ikemoto N., Keaton K.A., Kraft M., Lazerwith S.E., Leeman M., Peng Z., et al. Synthesis of Polycyclic-Carbamoylpyridone Compounds. US20150368264A1. 2015 December 24;
  • 131.Hughes D.L. Review of Synthetic Routes and Final Forms of Integrase Inhibitors Dolutegravir, Cabotegravir, and Bictegravir. Org. Process Res. Dev. 2019;23:716–729. doi: 10.1021/acs.oprd.9b00031. [DOI] [Google Scholar]
  • 132.Doi Y. Treatment Options for Carbapenem-Resistant Gram-Negative Bacterial Infections. Clin. Infect. Dis. 2019;69:565–575. doi: 10.1093/cid/ciz830. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 133.Voelker R. New Antibacterial Should be Used With Caution. J. Am. Med. Assoc. 2019;322:807. doi: 10.1001/jama.2019.12939. [DOI] [PubMed] [Google Scholar]
  • 134.Miller S.P., Limanto J., Zhong Y.L., Yasuda N., Liu Z. Preparation of Tert-Butyl 4-((1R,2S,5R)-6-(benzyloxy)-7-oxo-1,6-diazabicyclo[3.2.1]octane-2- Carboxamido Piperidine-1-Carboxylate. WO2014200786. 2014 December 18;
  • 135.Terasawa H., Ejima A., Ohsuki S., Uoto K. Hexa-cyclic Compound. US5834476. 1998 November 10;
  • 136.Markham A. Pralsetinib: First Approval. Drugs. 2020;80:1865–1870. doi: 10.1007/s40265-020-01427-4. [DOI] [PubMed] [Google Scholar]
  • 137.Brubaker J.D., Kim J.L., Wilson K.J., Wilson D., DiPietro L.V. Inhibitors of RET. US20170121312. 2018 July 24;
  • 138.Scott L.J. Rimegepant: First Approval. Drugs. 2020;80:741–746. doi: 10.1007/s40265-020-01301-3. [DOI] [PubMed] [Google Scholar]
  • 139.Luo G., Chen L., Conway C.M., Denton R., Keavy D., Signor L., Kostich W., Lentz K.A., Santone K.S., Schartman R., et al. Discovery of (5S,6S,9R)-5-amino-6-(2,3- difluorophenyl)-6,7,8,9-tetrahydro-5H-cyclohepta[b]pyri din-9-yl-4-(2-oxo2,3-dihydro-1H-imidazo[4,5-b]pyridin-1-yl)piperidine-1-carboxylate (BMS927711): An Oral Calcitonin Gene-Related Peptide (CGRP) Antagonist in Clinical Trials for Treating Migraine. J. Med. Chem. 2012;55:10644–10651. doi: 10.1021/jm3013147. [DOI] [PubMed] [Google Scholar]
  • 140.Markham A. Migalastat: First Global Approval. Drugs. 2016;76:1147–1152. doi: 10.1007/s40265-016-0607-y. [DOI] [PubMed] [Google Scholar]
  • 141.Stuetz A., Steiner A., Wrodnigg T. Preparation of IminoSugar Glycopeptide Conjugates via Catalytic Intramolecular Reductive Amination Reaction. EP 1,903,034. 2008 March 26;
  • 142.Kim E.S. Midostaurin: First Global Approval. Drugs. 2017;77:1251–1259. doi: 10.1007/s40265-017-0779-0. [DOI] [PubMed] [Google Scholar]
  • 143.Hoehn P., Koch B., Mutz M. Process for Purifying Staurosporine. EP 2272850 B1. 2017 May 10;
  • 144.Markham A. Naldemedine: First Global Approval. Drugs. 2017;77:923–927. doi: 10.1007/s40265-017-0750-0. [DOI] [PubMed] [Google Scholar]
  • 145.Tamura Y., Noguchi K., Inagaki M., Morimoto K., Haga N., Oda S., Omura S. Crystal of 6,7-Unsaturated-7-carbamoyl Morphinan Derivative and Method for Producing the Same. US 9108975B2. 2016 April 19;
  • 146.Citrome L. Valbenazine for Tardive Dyskinesia: A Systematic Review of the Efficacy and Safety Profile for This Newly Approved Novel Medication—What Is the Number Needed to Treat, Number Needed to Harm and Likelihood to Be Helped or Harmed? Int. J. Clin. Pract. 2017;71:e12964. doi: 10.1111/ijcp.12964. [DOI] [PubMed] [Google Scholar]
  • 147.Boldt K.G., Biggers M.S., Phifer S.S., Brine G.A., Rehder K.S. Synthesis of (+)- and (−)-Tetrabenazine from the Resolution of A-Dihydrotetrabenazine. Synth. Commun. 2009;39:3574–3585. doi: 10.1080/00397910902788125. [DOI] [Google Scholar]
  • 148.Xiao X.-Y., Hunt D.K., Zhou J., Clark R.B., Dunwoody N., Fyfe C., Grossman T.H., O’Brien W.J., Plamondon L., Ronn M., et al. Fluorocyclines. 1. 7-Fluoro-9-Pyrrolidinoacetamido-6-Demethyl-6-Deoxytetracycline: A Potent, Broad Spectrum Antibacterial Agent. J. Med. Chem. 2012;55:597–605. doi: 10.1021/jm201465w. [DOI] [PubMed] [Google Scholar]
  • 149.Zhang W.-Y., Che Q., Crawford S., Ronn M., Dunwoody N. A Divergent Route to Eravacycline. J. Org. Chem. 2017;82:936–943. doi: 10.1021/acs.joc.6b02442. [DOI] [PubMed] [Google Scholar]
  • 150.Zhou J., Xiao X.-Y., Plamondon L., Hunt D.K., Clark R.B., Zahler R.B. Preparation of C7-Fluoro Substituted Tetracycline Compounds as Antibacterial Agents. WO 2010017470A1. 2014 August 5;
  • 151.Zhang W.-Y., Hogan P.C., Chen C.-L., Niu J., Wang Z., Lafrance D., Gilicky O., Dunwoody N., Ronn M. Process Research and Development of an Enantiomerically Enriched Allylic Amine, One of the Key Intermediates for the Manufacture of Synthetic Tetracyclines. Org. Process Res. Dev. 2015;19:1784–1795. doi: 10.1021/acs.oprd.5b00274. [DOI] [Google Scholar]
  • 152.Deeks E.D. Sarecycline: First Global Approval. Drugs. 2019;79:325–329. doi: 10.1007/s40265-019-1053-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 153.Abato P., Assefa H., Berniac J., Bhatia B., Bowser T., Grier M., Honeyman L., Ismail M., Kim O.K., Nelson M., et al. Substituted Tetracycline Compounds for Treatment of Bacterial Infections and Neoplasms. WO2008079339A1. 2008 July 3;
  • 154.Nelson M.L., McIntyre L. Preparation of 7-Substituted Fused Ring Tetracycline Compounds as Antibiotics. WO2001087824A1. 2001 November 22;
  • 155.Tanaka S.K., Steenbergen J., Villano S. Discovery, Pharmacology, and Clinical Profile of Omadacycline, a Novel Aminomethylcycline Antibiotic. Bioorg. Med. Chem. 2016;24:6409–6419. doi: 10.1016/j.bmc.2016.07.029. [DOI] [PubMed] [Google Scholar]
  • 156.Markham A., Keam S.J. Omadacycline: First Global Approval. Drugs. 2018;78:1931–1937. doi: 10.1007/s40265-018-1015-2. [DOI] [PubMed] [Google Scholar]
  • 157.Johnston S., Warchol T. Methods for Synthesizing and Purifying Aminoalkyl Tetracycline Compounds. WO2008134048A1. 2008 November 6;
  • 158.Keam S.J. Vibegron: First Global Approval. Drugs. 2018;78:1835–1839. doi: 10.1007/s40265-018-1006-3. [DOI] [PubMed] [Google Scholar]
  • 159.Xu F., Kosjek B., Cabirol F.L., Chen H., Desmond R., Park J., Gohel A.P., Collier S.J., Smith D.J., Liu Z., et al. Synthesis of Vibegron Enabled by a Ketoreductase Rationally Designed for High Ph Dynamic Kinetic Reduction. Angew. Chem. Int. Ed. 2018;57:6863–6867. doi: 10.1002/anie.201802791. [DOI] [PubMed] [Google Scholar]
  • 160.Dodick D.W., Lipton R.B., Ailani J., Lu K., Finnegan M., Trugman J.M., Szegedi A. Ubrogepant for the Treatment of Migraine. N. Engl. J. Med. 2019;381:2230–2241. doi: 10.1056/NEJMoa1813049. [DOI] [PubMed] [Google Scholar]
  • 161.Bell I.M., Fraley M.E., Gallicchio S.N., Ginnetti A., Mitchell H.J., Paone D.V., Staas D.D., Stevenson H.E., Wang C., Zartman C.B. Piperidinone Carboxamide Azaindane CGRP Receptor Antagonists. WO2012064910. 2012 May 18;
  • 162.Dhillon S. Decitabine/Cedazuridine: First Approval. Drugs. 2020;80:1373–1378. doi: 10.1007/s40265-020-01389-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 163.Ferraris D., Duvall B., Delahanty G., Mistry B., Alt J., Rojas C., Rowbottom C., Sanders K., Schuck E., Huang K.C., et al. Design, Synthesis, and Pharmacological Evaluation of Fluorinated Tetrahydrouridine Derivatives as Inhibitors of Cytidine Deaminase. J. Med. Chem. 2014;57:2582–2588. doi: 10.1021/jm401856k. [DOI] [PubMed] [Google Scholar]
  • 164.Edmondson S.D., Zhu C., Kar N.F., Di Salvo J., Nagabukuro H., Sacre-Salem B., Dingley K., Berger R., Goble S.D., Morriello G., et al. Discovery of Vibegron: A Potent and Selective Beta3 Adrenergic Receptor Agonist for the Treatment of Overactive Bladder. j. Med. Chem. 2016;59:609–623. doi: 10.1021/acs.jmedchem.5b01372. [DOI] [PubMed] [Google Scholar]
  • 165.de Bruijne J., Bergmann J.F., Reesink H.W., Weegink C.J., Molenkamp R., Schinkel J., Tong X., Li J., Treitel A., Hughes E.A., et al. Antiviral Activity of Narlaprevir Combined with Ritonavir and Pegylated Interferon in Chronic Hepatitis C Patients. Hepatology. 2010;52:1590–1599. doi: 10.1002/hep.23899. [DOI] [PubMed] [Google Scholar]
  • 166.Traverse J., Leong W.M., Miller S.P., Albaneze-Walker J., Hunter T.J., Wang L., Liao H., Arasappan A., Trzaska S.T., Smith R.M., et al. Enantio- and Stereo Specific Synthesis of β-Amino-αHydroxy Amides. US 8680294B2. 2014 March 25;
  • 167.Traverse J., Leong W.W., Miller S.P., Albaneze-Walker J., Hunter T.J., Wang L., Liao H., Arasappan A., Trzaska S.T., Smith R.M., et al. Processes for Enantioand Stereospecific Syntheses of β-Amino-α-Hydroxy Amides. WO 2011014494 A1. 2011 February 3;
  • 168.Keating G.M. Elbasvir/Grazoprevir: First Global Approval. Drugs. 2016;76:617–624. doi: 10.1007/s40265-016-0558-3. [DOI] [PubMed] [Google Scholar]
  • 169.Hayes A.M., Morris D.J., Clarkson G.J., Wills M. A Class of Ruthenium(II) Catalyst for Asymmetric Transfer Hydrogenations of Ketones. J. Am. Chem. Soc. 2005;127:7318–7319. doi: 10.1021/ja051486s. [DOI] [PubMed] [Google Scholar]
  • 170.Impagnatiello F., Bastia E., Almirante N., Brambilla S., Duquesroix B., Kothe A.C., Bergamini M.V.W. Prostaglandin Analogues and Nitric Oxide Contribution in the Treatment of Ocular Hypertension and Glaucoma. Br. J. Pharmacol. 2019;176:1079–1089. doi: 10.1111/bph.14328. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 171.Ongini E., Benedini F., Chiroli V., Del Soldato P. Preparation of Prostaglandin Nitrooxy Derivatives for the Treatment of Glaucoma. WO 2005068421. 2006 February 9;
  • 172.Vittitow J.L., Cavet M.E. Nitric Oxide Releasing Prostaglandin Derivatives for Treating Normal Tension Glaucoma. WO 2018087092. 2018 May 17;
  • 173.Markham A., Keam S.J. Danoprevir: First Global Approval. Drugs. 2018;78:1271–1276. doi: 10.1007/s40265-018-0960-0. [DOI] [PubMed] [Google Scholar]
  • 174.Beaulieu P.L., Gillard J., Bailey M.D., Boucher C., Duceppe J.-S., Simoneau B., Wang X.-J., Zhang L., Grozinger K., Houpis I., et al. Synthesis of (1r,2s)-1-Amino-2-Vinylcyclopropanecarboxylic Acid Vinyl-ACCA) Derivatives: Key Intermediates for the Preparation of Inhibitors of the Hepatitis C Virus NS3 Protease. J. Org. Chem. 2005;70:5869–5879. doi: 10.1021/jo050468q. [DOI] [PubMed] [Google Scholar]
  • 175.Greig S.L. Sofosbuvir/Velpatasvir: A Review in Chronic Hepatitis C. Drugs. 2016;76:1567–1578. doi: 10.1007/s40265-016-0648-2. [DOI] [PubMed] [Google Scholar]
  • 176.Allan K.M., Fujimori S., Heumann L.V., Huynh G.M., Keaton K.A., Levins C.M., Pamulapati G.R., Roberts B.J., Sarma K., Teresk M.G., et al. Processes for Preparing Peptide Analog as Antiviral Agent. WO 2015191437A1. 2015 December 17;
  • 177.Nevens F., Andreone P., Mazzella G., Strasser S.I., Bowlus C., Invernizzi P., Drenth J.P.H., Pockros P.J., Regula J., Beuers U., et al. A Placebo-Controlled Trial of Obeticholic Acid in Primary Biliary Cholangitis. N. Engl. J. Med. 2016;375:631–643. doi: 10.1056/NEJMoa1509840. [DOI] [PubMed] [Google Scholar]
  • 178.Steiner A., Waenerlund Poulsen H., Jolibois E., Rewolinski M., Gross R., Sharp E., Dubas-Fisher F., Eberlin A. Preparation and Uses of Obeticholic Acid. WO 20130345188. 2016 January 19;
  • 179.Ferrari M., Pellicciari R. Process for Preparing 3a(β)-7a(β)- Dihydroxy-6a(β)-Alkyl-5β-Cholanic Acid. US 7994352. 2011 August 9;
  • 180.Bassan E.M., Baxter C.A., Beutner G.L., Emerson K.M., Fleitz F.J., Johnson S., Keen S., Kim M.M., Kuethe J.T., Leonard W.R., et al. Multikilogram Scale Synthesis of a Chiral Cyclopropanol and an Investigation of the Safe Use of Lithium Acetylide−Ethylene Diamine Complex. Org. Process Res. Dev. 2012;16:87–95. doi: 10.1021/op2002497. [DOI] [Google Scholar]
  • 181.Markham A. Ertugliflozin: First Global Approval. Drugs. 2018;78:513–519. doi: 10.1007/s40265-018-0878-6. [DOI] [PubMed] [Google Scholar]
  • 182.Bowles P., Brenek S.J., Caron S., Do N.M., Drexler M.T., Duan S., Dube P., Hansen E.C., Jones B.P., Jones K.N., et al. Commercial Route Research and Development for Sglt2 Inhibitor Candidate Ertugliflozin. Org. Process Res. Dev. 2014;18:66–81. doi: 10.1021/op4002802. [DOI] [Google Scholar]
  • 183.Heo Y.-A., Deeks E.D. Sofosbuvir/Velpatasvir/Voxilaprevir: A Review in Chronic Hepatitis C. Drugs. 2018;78:577–587. doi: 10.1007/s40265-018-0895-5. [DOI] [PubMed] [Google Scholar]
  • 184.Cagulada A., Chan J., Chan L., Colby D.A., Karki K.K., Kato D., Keaton K.A., Kondapally S., Levins C., Littke A., et al. Synthesis of an Antiviral N-(3-Ethyl)prolyl-1- aminocyclopropanecarboxylic Acid Peptide and New Routes to Its Difluoromethylaminocyclopropanecarboxylic Acid Intermediate. US 20150175626A1. 2016 September 13;
  • 185.Lamb Y.N. Glecaprevir/Pibrentasvir: First Global Approval. Drugs. 2017;77:1797–1804. doi: 10.1007/s40265-017-0817-y. [DOI] [PubMed] [Google Scholar]
  • 186.Periasamy M., Seenivasaperumal M., Rao V.D. Convenient Procedures for the Asymmetric Reduction of 1,4- Diphenylbutane-1,4-Dione and Synthesis of 2,5-Diphenylpyrrolidine Derivatives. Synthesis. 2003;35:2507–2510. doi: 10.1055/s-2003-42447. [DOI] [Google Scholar]
  • 187.Bjornson K., Karki K.K., Link J.O., Pyun H.-J., Schrier A.J., Stevens K.L., Taylor J.G., Vivian R.W., Zablocki J., Zipfel S. Preparation of Macrocyclic and Bicyclic Derivatives of N-Prolyl-1- aminocyclopropanecarboxylic Acid Peptides as Inhibitors of Hepatitis C Virus. WO 2014145095A1. 2014 September 18;
  • 188.Mehrhof W., Irmscher K., Erb R., Pohl L. Synthesewege Zum 17a-Hydroxy-16-Methylen-19-nor-Progesteron Und Seinen Derivaten. Chem. Ber. 1969;102:643–658. doi: 10.1002/cber.19691020231. [DOI] [PubMed] [Google Scholar]
  • 189.Urdiales J., Morata P., De Castro I.N., Sánchez-Jiménez F. Antiproliferative Effect of Dehydrodidemnin B (DDB), a Depsipeptide Isolated from Mediterranean Tunicates. Cancer Lett. 1996;102:31–37. doi: 10.1016/0304-3835(96)04151-1. [DOI] [PubMed] [Google Scholar]
  • 190.Rodriguez I., Polanco C., Cuevas F., Mandez P., Cuevas C., Gallego P., Munt S., Manzanares I. Synthetic Methods for Aplidine and New Antitumoral Derivatives, Methods of Making and Using Them. WO2002002596A2. 2002 May 23;
  • 191.Wilby K.J., Eissa N.A. Clinical Pharmacokinetics and Drug Interactions of Doravirine. Eur. J. Drug. Metab. Pharmacokinet. 2018;43:637–644. doi: 10.1007/s13318-018-0497-3. [DOI] [PubMed] [Google Scholar]
  • 192.Dai Y., Du Z., Wang R. Preparation of Moxidectin. CN104017001B. 2016 January 13;
  • 193.McCarthy M.W. Plazomicin for the Treatment of Patients with Complicated Urinary Tract Infection. Drugs Today. 2017;54:513–518. doi: 10.1358/dot.2018.54.9.2874063. [DOI] [PubMed] [Google Scholar]
  • 194.Nagabhushan T.L. Process for the Manufacture of 6′-NAlkyl Derivatives of Sisomicin and Verdamicin; Novel Intermediate Useful Therein, and Novel 6′-N-Alkylverdamicins Prepared Thereby. US3997524A. 1976 December 14;
  • 195.Aggen J., Goldblum A.A., Linsell M., Dozzo P., Moser H.E., Hildebrandt D., Gliedt M. Antibacterial Aminoglycoside Analogs. WO2009067692A1. 2009 May 28;
  • 196.Aggen J.B., Armstrong E.S., Goldblum A.A., Dozzo P., Linsell M.S., Gliedt M.J., Hildebrandt D.J., Feeney L.A., Kubo A., Matias R.D., et al. Synthesis and Spectrum of the Neoglycoside ACHN490. Antimicrob. Agents Chemother. 2010;54:4636–4642. doi: 10.1128/AAC.00572-10. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 197.Bruss J.B., Miller G.H., Aggen J.B., Armstrong E.S. Treatment of Urinary Tract Infections with Antibacterial Aminoglycoside Compounds. WO2010132777A2. 2011 January 20;
  • 198.Bruss J.B., Miller G.H., Aggen J.B., Armstrong E.S. Treatment of Klebsiella Pneumoniae Infections with Antibacterial Aminoglycoside Compounds. WO2010132770A1. 2010 November 18;
  • 199.Trend R., Dappen M., Henry C.E., Goldblum A.A., Aggen J.B., Mendonca R.F.d.J.G., Sardinha J.C.F. Synthesis of Antibacterial Aminoglycoside Analogs. WO2019079613A1. 2019 April 25;
  • 200.Hoy S.M. Tecovirimat: First Global Approval. Drugs. 2018;78:1377–1382. doi: 10.1007/s40265-018-0967-6. [DOI] [PubMed] [Google Scholar]
  • 201.Hughes D.L. Review of the Patent Literature: Synthesis and Final Forms of Antiviral Drugs Tecovirimat and Baloxavir Marboxil. Org. Process Res. Dev. 2019;23:1298–1307. doi: 10.1021/acs.oprd.9b00144. [DOI] [Google Scholar]
  • 202.Voelker R. New Antibiotic for Community-Acquired Pneumonia. J. Am. Med. Assoc. 2019;322:1246. doi: 10.1001/jama.2019.15179. [DOI] [PubMed] [Google Scholar]
  • 203.Riedl R., Heilmayer W., Spence L. Process for the Preparation of Pleuromutilins in Crystalline Form. WO201114. 2011 December 1;
  • 204.Langendonk J.G., Balwani M., Anderson K.E., Bonkovsky H.L., Anstey A.V., Bissell D.M., Bloomer J., Edwards C., Neumann N.J., Parker C., et al. Afamelanotide for Erythropoietic Protoporphyria. N. Engl. J. Med. 2015;373:48–59. doi: 10.1056/NEJMoa1411481. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 205.Robert D., Jung L. Aromatic Amides Absorbing the UV. WO1987004923. 1987 August 27;
  • 206.Lensing C.J., Freeman K.T., Schnell S.M., Speth R.C., Zarth A.T., HaskellLuevano C. Developing a Biased Unmatched Bivalent Ligand (BUmBL) Design Strategy to Target the GPCR Homodimer Allosteric Signaling (cAMP over barrestin 2 recruitment) Within the Melanocortin Receptors. J. Med. Chem. 2019;62:144–158. doi: 10.1021/acs.jmedchem.8b00238. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 207.Scott L.J. Brexanolone: First Global Approval. Drugs. 2019;79:779–783. doi: 10.1007/s40265-019-01121-0. [DOI] [PubMed] [Google Scholar]
  • 208.MacNevin C.J., Atif F., Sayeed I., Stein D.G., Liotta D.C. Development and Screening of Water-Soluble Analogues of Progesterone and Allopregnanolone in Models of Brain Injury. J. Med. Chem. 2009;52:6012–6023. doi: 10.1021/jm900712n. [DOI] [PubMed] [Google Scholar]
  • 209.Dhillon S., Keam S.J. Bremelanotide: First Approval. Drugs. 2019;79:1599–1606. doi: 10.1007/s40265-019-01187-w. [DOI] [PubMed] [Google Scholar]
  • 210.Yan L., Wang B., Li J., Jin Y., Wang J., Yang Z. A Synthetic Method for Bremelanotide. CN10658911. 2020 December 29;
  • 211.Markham A. Lurbinectedin: First Approval. Drugs. 2020;80:1345–1353. doi: 10.1007/s40265-020-01374-0. [DOI] [PubMed] [Google Scholar]
  • 212.He W., Zhang Z., Ma D. A scalable Total Synthesis of the Antitumor Agents Et743 and Lurbinectedin. Angew. Chem. Int. Ed. Engl. 2019;58:3972–3975. doi: 10.1002/anie.201900035. [DOI] [PubMed] [Google Scholar]
  • 213.Li X.Q., Zhang X.M., Wu X., Lan Y., Xu L., Meng X.C., Li J.N. Beneficial Effects of Lactitol on the Composition of Gut Microbiota in Constipated Patients. J. Dig. Dis. 2020;21:445–453. doi: 10.1111/1751-2980.12912. [DOI] [PubMed] [Google Scholar]
  • 214.Sun T.J., Yang J., Lu H.G., Zhao W.J., Feng J.P., Gao L.H., Zhu N.Q., Zhang H.Y., Huo H.H., Zhang Y.B. Preparation of Lactitol. CN101481395. 2011 August 31;
  • 215.Haws R., Brady S., Davis E., Fletty K., Yuan G., Gordon G., Stewart M., Yanovski J. Effect of Setmelanotide, A Melanocortin-4 Receptor Agonist, on Obesity in Bardet-Biedl Syndrome. Diabetes Obes. Metabol. 2020;22:2133–2140. doi: 10.1111/dom.14133. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 216.Zheng Xin D. Process for the Synthesis of Ac-Arg-cyclo(Cys-D-Ala-His-DPhe-Arg-Trp-Cys)-NH2. WO2011060355. 2011 May 19;
  • 217.Dhillon S. Clascoterone: First Approval. Drugs. 2020;80:1745–1750. doi: 10.1007/s40265-020-01417-6. [DOI] [PubMed] [Google Scholar]
  • 218.Ajani M., Moro L. Enzymatic Process for Obtaining 17 Alpha-Monoesters of Cortexolone And/or its 9,11-dehydroderivatives. WO2009019138. 2009 October 15;
  • 219.Dong P.X., Mei Z., Zhao Z.J., Yi Y.Y. Simple Process for Preparing Artesunate by One-Pot Method by Taking Artemisinin as Raw Material. CN 102887908. 2013 January 23;
  • 220.Lamb Y.N. Remdesivir: First Approval. Drugs. 2020;80:1355–1363. doi: 10.1007/s40265-020-01378-w. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 221.Clarke M.O.H., Jordan R., Mackman R.L., Ray A.S., Siegel D. Methods for Treating Flaviviridae Virus Infections. WO2017184668. 2017 October 26;

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Data Availability Statement

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