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. 2021 Apr 16;2021:6638229. doi: 10.1155/2021/6638229

Preparation and Thermogravimetric and Antimicrobial Investigation of Cd (II) and Sn (II) Adducts of Mercaptopyridine, Amino Triazole Derivatives, and Mercaptothiazoline Organic Ligand Moieties

Ahmed Gaber 1, Walaa F Alsanie 2, Robson F de Farias 3, Moamen S Refat 4,✉
PMCID: PMC8064795  PMID: 33953737

Abstract

The solid adducts of SnCl2.(3amt).H2O, SnCl2.2(3amt).H2O, CdCl2.(3amt), CdCl2.2(3amt), SnCl2.(2mct).0.5H2O, SnCl2.2(2mct), CdCl2.(2mct), CdCl2.2(2mct).H2O, SnCl2.(2mcp).1.5H2O, >2.2(2mcp).4H2O, CdCl2.(2mcp), CdCl2.2(2mcp), SnCl2.(4amt).4H2O, SnCl2.2(4amt).1.5H2O, CdCl2.(4amt).H2O, and CdCl2.2(4amt) (where the 3amt, 4amt, 2mct, and 2mcp represent 3-amino-1,2,4-triazole, 4-amino-1,2,4-triazole, 2-mercaptothiazoline, and 2-mercaptopyridine simple organic chelates, respectively) were prepared using a solid-state route and investigated by CHN elemental analysis and infrared spectroscopy. Additionally, we investigated the thermogravimetric characterization and antimicrobial proprieties. It is verified that for 3amt and 4amt adducts, the coordination occurs through nitrogen atom. For 2mct compounds, the coordination occurs through nitrogen (Sn) or sulfur (Cd). For 2mcp adducts, both coordination sites nitrogen and sulfur are involved. By examination of TG curves, it is confirmed that for each hydrated compounds, the first mass loss step is linked with the release of water molecules followed by the release of ligand molecules and sublimation of the metal chloride. Furthermore, it is verified that, considering only the release of ligand molecules (3amp, 4amp, 2mct, or 2mcp), the cadmium adducts are always more stable than the correspondent tin adducts probably due to the formation of cross-linking bonds in these compounds. Finally, of these 16 adducts, 14 showed antimicrobial activities against different bacterial and fungal strains.

1. Introduction

In the past decades, the problem of multidrug-resistant microorganisms has reached an alarming level worldwide, and the synthesis of new antimicrobial compounds has become an urgent need to treat microbial infections. Organic compounds that include heterocyclic ring systems continue to attract significant interest due to their wide range of biological elements [1]. The nucleus 1,2,4-triazole is incorporated into a variety of important therapeutic agents, which mainly exhibit antimicrobial activities [1, 2]. Among the various five-membered heterocyclic systems, 1,2,4-triazoles and 1,3,4-thiadiazoles and their derivatives gain importance because they constitute the structural features of many bioactive compounds [2]. Triazole and thiadiazole rings are known to be included in the structure of various drugs [3, 4]. From these classes of heterocyclic compounds, the synthesis of novel derivatives of 1,2,4-triazole-3-thionate and 2-amino-1,3,4-thiazole has attracted great interest due to various biological properties such as antibacterial [5, 6], antifungal [7], antituberculosis [8, 9], interferon [10], antioxidant [11], antitumor [12], anti-inflammatory [13, 14], and anticonvulsant [15].

The thermogravimetry analysis technique is employed to identify the acceptability level regarding the coordination nature in between the central metal ions and different kinds of interesting biomolecule chelates, such as amino acids [16], caffeine molecule [17], or chemical materials that have a biological behavior as ethylene- and propylene-urea as well as ethylene-thiourea [18]. Moreover, the thermogravimetric information shows very close relationships with the calorimetric data [19] and the spectral data [20].

The main goal of this article is to investigate the synthesis, thermal analyses, and antimicrobial data of the sixteen solid adducts for the Cd (II) and Sn (II) metal ions coordinated with the 3amt, 4amt, 2mct, or 2mcp organic molecules. The molecular structural formulas of 3amt, 4amt, 2mct, and 2mcp are displayed in Figure 1. The sixteen solid adducts are SnCl2.(3amt).H2O, SnCl2.2(3amt).H2O, CdCl2.(3amt), CdCl2.2(3amt), SnCl2.(2mct).0.5H2O, SnCl2.2(2mct), CdCl2.(2mct), CdCl2.2(2mct).H2O, SnCl2.(2mcp).1.5H2O, SnCl2.2(2mcp).4H2O, CdCl2.(2mcp), CdCl2. 2(2mcp), SnCl2.(4amt).4H2O, SnCl2.2(4amt).1.5H2O, CdCl2.(4amt).H2O, and CdCl2.2(4amt).

Figure 1.

Figure 1

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The structural forms of 3amt, 4amt, 2mct, and 2mcp.

2. Materials and Methods

All used reagents were purchased from Sigma-Aldrich and were utilized with no additional purification.

All solid Cd(II) and Sn(II) adducts were prepared by the solid-state pathway by grinding stoichiometric amounts of metal halides and organic moieties (3amt, 4amt, 2mct, and 2mcp) in a mortar for 70 minutes at room temperature (27°C). The prepared solid adducts were dried under vacuum at room temperature for 24 h. This solid-state pathway was successfully used to enhance coordination reactions [21–24] as an alternative to conventional synthesis in solution. The synthesis is performed at room temperature, and where no solvent is used, any unwanted reaction to the metal cation is avoided. The infrared spectra result considering both free organic ligands and sixteen solid adducts proved that there are no free ligand particles after the grinding process.

C, H, and N elemental analysis were performed using a Perkin-Elmer 2400 analyzer. Infrared spectra of the solid adducts as a powder in situ KBr discs were scanned using a Gengis II FTIR apparatus within the 4000–400 cm−1 range, with a resolution of 4 cm−1. Thermogravimetric diagrams under N2 atmosphere were analyzed on the Shimadzu TG-50H apparatus with a heating rate of 15°C min−1.

Tin(II) and cadmium(II) contents were determined by gravimetry by the direct ignition of the adducts at 600°C for 3 h till constant weight. The residue was then weighted in the forms of SnO and CdO, respectively. The Mohr method uses chromate ions as an indicator in the titration of chloride ions with a silver nitrate standard solution. After all the chloride precipitated as white silver chloride, the first excess of titrant results in the formation of a silver chromate precipitate, which signals the end point.

Preparation of standard AgNO3 solution: 9.0 g of AgNO3 was weighed out, transferred to a 500 mL volumetric flask, and made up to volume with distilled water. The resulting solution was approximately 0.1 M. This solution was standardized against NaCl. Reagent-grade NaCl was dried overnight and cooled to room temperature. 0.25 g portions of NaCl were weighed into Erlenmeyer flasks and dissolved in about 100 mL of distilled water. In order to adjust the pH of the solutions, small quantities of NaHCO3 were added until effervescence ceased. About 2 mL of K2CrO4 was added, and the solution was titrated to the first permanent appearance of red Ag2CrO4.

The antimicrobial activity of all adducts were performed as previously explained in detail by Gaber et al. [21]. Escherichia coli and Pseudomonas aeruginosa were used as Gram-negative bacteria, whereas Bacillus subtilis and Staphylococcus aureus were used as Gram-positive bacteria. In addition, Aspergillus flavus and Candida albicans were used as fungal strains. Diameters of the inhibition zones around the hole were calculated [21].

3. Results and Discussion

Table 1 shows the data of the elemental analysis. These results are like the proposed formulas. Additionally, the main infrared bands are displayed in Tables 2–5. Before a discussion on the infrared data, it is important to note that considering (3amt and 4amt) and (2mct and 2mcp), organic molecules have a rich electron donor sites through the lone pair of electrons presented on the nitrogen and sulfur atoms, respectively. Moreover, for the four chelates, there is more than one potential coordination site, which makes them able, at the very first moment, to act as cross-links.

Table 1.

Mass weight and carbon, hydrogen, and nitrogen elemental analysis data for the examined compounds.

Adducts M.wt % C % H % N
Calc. Found Calc. Found Calc. Found
SnCl2.(3amt).H2O 291.68 8.22 8.11 2.05 2.02 19.19 18.94
SnCl2.2(3amt).H2O 375.76 12.77 12.25 2.66 2.61 29.81 29.44
CdCl2.(3amt) 267.37 8.97 8.89 1.49 1.45 20.94 20.73
CdCl2.2(3amt) 351.47 13.65 13.62 2.27 2.20 31.87 31.48
SnCl2.(2mct).0.5H2O 317.81 11.33 10.99 1.89 1.84 4.40 4.35
SnCl2.2(2mct) 428.02 16.82 16.32 2.33 2.28 6.54 6.43
CdCl2.(2mct) 302.52 11.90 11.74 1.65 1.59 4.62 4.55
CdCl2.2(2mct).H2O 439.73 16.37 16.22 2.73 2.68 6.37 6.18
SnCl2.(2mcp).1.5H2O 327.77 18.31 18.19 2.44 2.41 4.27 4.15
SnCl2.2(2mcp).4H2O 483.94 24.80 24.57 3.72 3.68 5.78 5.74
CdCl2.(2mcp) 294.48 20.37 20.22 1.69 1.68 4.75 4.72
CdCl2.2(2mcp) 405.65 29.58 29.29 2.46 2.45 6.90 6.84
SnCl2.(4amt).4H2O 345.68 6.94 6.91 3.47 3.41 16.19 15.98
SnCl2.2(4amt).1.5H2O 384.76 12.48 12.34 2.86 2.79 29.11 28.96
CdCl2.(4amt).H2O 285.37 8.40 8.34 2.10 2.07 19.62 19.48
CdCl2.2(4amt) 351.47 13.65 13.51 2.27 2.26 31.87 31.83
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Table 2.

Major infrared bands (cm−1) for 3amt and its Cd(II) and Sn(II) adducts.

3amt CdCl2-(3amt) CdCl2-2(3amt) SnCl2-(3amt) SnCl2-2(3amt) Assignments
3398 s 3419 ms 3340 ms 3312 w 3349 vw v as (N-H); NH2
3326 mw 3356 w     3310 vw  
3316 mw     3258 vw  
3182 mw 3213 w 3212 ms 3155 mw 3155 ms v s (N-H); NH2
  3131 w 3153 vw      
1647 vs 1652 vs 1645 w, sh 1688 vs 1677 vs δ b(NH2)
1590 s 1573 w 1594 vs 1569 ms 1566 ms ν (C=N)
1533 s 1537 s 1560 vs     ν (N=N)
  1480 w 1479 vs      
1418 s 1429 ms 1374 vs 1405 mw 1415 w Ring breathing bands
1389 ms 1373 w   1339 ms 1326 s  
  1332 ms        
1275 vs 1283 s 1248 vs 1257 ms 1263 w ρ r (NH2)
1217 vs 1250 vw 1213 ms 1125 vw 1125 ms ν (C-N)
  1219 vs 1144 vs      
  1144 w        
1045 vs 1088 w 1083 vs 1048 s 1066 s ρ w (NH2)
945 vs 1057 s 1011 vs 951 vs 950 vs  
  991 s        
873 vs 901 s 884 s 860 ms 867 s ρ t (NH2)
830 s 740 ms 747 sh 748 w, sh 773 ms  
729 vs 693 vw 726 ms      
  644 vs 694 vs      
    642 ms      
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s = strong; w = weak; m = medium; sh = shoulder; v = very; br = broad; ν = stretching; δ = bending.

Table 3.

Major infrared bands (cm−1) for 4amt and its Cd(II) and Sn(II) adducts.

4amt CdCl2-(4amt) CdCl2-2(4amt) SnCl2-(4amt) SnCl2-2(4amt) Assignments
3312 w 3467 ms 3303 s 3417 w 3418 w, br v as (N-H); NH2
  3368 ms 3258 vw 3317 ms 3277 w, br  
  3307 ms        
3197 w 3199 s 3198 s 3127 ms 3129 w, br v s (N-H); NH2
3139 w 3136 s 3105 s      
1647 vs 1618 vs 1618 vs 1623 vs 1685 w δ b(NH2)
1533 s 1543 s 1537 s 1539 ms 1631 vs  
        1529 s  
1475 ms 1474 mw 1470 w 1465 vw 1465 vw Ring breathing bands
1404 s 1398 s 1394 w 1402 vw 1412 vw  
  1341 s 1346 w 1366 vw 1363 vw  
      1318 vw 1323 vw  
1188 s 1209 s 1209 ms 1207 ms 1205 s ρ r (NH2)
1074 s 1145 vw 1078 s 1164 vw 1075s ν (C–N)
  1082 vs   1135 vw    
      1075 s    
1016 vw 1025 s 1015 s 1034 s 1033 s ρ w (NH2)
959 ms 980 vs 984 ms 934 ms 935 ms  
873 s 908 w 894 ms 871 ms 875 ms ρ t (NH2)
672 w 874 s 845 vw 690 w, sh 661 ms  
  689 ms 686 ms      
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s = strong; w = weak; m = medium; sh = shoulder; v = very; br = broad; ν = stretching; δ = bending.

Table 4.

Major infrared bands (cm−1) for 2mct and its Cd(II) and Sn(II) adducts.

2mct CdCl2-(2mct) CdCl2-2(2mct) SnCl2-(2mct) SnCl2-2(2mct) Assignments
2852 w 3258 s 3258 s 3443 s, br 3447 ms, br v s (C-H); –CH2
  2948 vw 3136 ms 3206 ms 3207 w v (O-H); H2O
    2998 w 3144 vw 3136 w  
    2947 w 2997 w 2997 w  
    2844 w 2929 w 2848 vw  
      2845 w    
2709 mw — — — — ν (SH)
2565 mw          
1518 vs 1515 vs 1515 vs 1539 vs 1539 w, sh ν (C=N)
        1514 s Ring breathing bands
1260 w 1308 s 1305 s 1307 s 1294 s v as (C-N)
1217 w 1250 vw 1249 w 1253 w 1250 vw v s (C-N) +  ν (C-C)
1160 w 1192 ms 1193 s 1208 w 1205 vw ν (C-S); C – SH
1102 s 1142 w 1045 vs 1167 w 1041 s  
  1045 vs   1038 s    
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s = strong; w = weak; m = medium; sh = shoulder; v = very; br = broad; ν = stretching; δ = bending.

Table 5.

Major infrared bands (cm−1) for 2mcp and its Cd(II) and Sn(II) adducts.

2mcp CdCl2-(2mcp) CdCl2-2(2mcp) SnCl2-(2mcp) SnCl2-2(2mcp) Assignments
— 3458 ms, br 3448 ms, br 3421 ms, br 3423 ms, br ν (OH); H2O
  3196 ms 3172 ms 3216 ms 3073 vw  
  3126 ms   3135 w    
  3087 s        
2709 mw — — — — ν (SH)
2537 mw          
1576 vs 1602 vs 1585 vs 1582 vs 1578 vs Ring breathing bands
1504 s 1517 s 1513 s 1550 sh 1551 sh  
1446 ms 1443 s 1443 s 1517 s 1438 vs  
1418 s 1378 s 1370 s 1438 vs 1366 w  
      1360 s    
1275 ms 1262 s 1252 s 1259 vs 1262 s ν (C=N); aromatic
1246 ms 1160 ms 1163 s 1155 w, sh 1179 vw δ(C-H); in-plane bend
1188 vs          
1145 vs 1134 vs 1132 vs 1131 s 1136 s ν (C-S); C – SH
1102 vw 1111 vw 1109 vw 1080 ms 1081 ms  
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s = strong; w = weak; m = medium; sh = shoulder; v = very; br = broad; ν = stretching; δ = bending.

In case of 3amt adducts, the overall decrease observed for the symmetrical and asymmetrical N-H bands suggests that the NH2 group is engaged with the coordination. Furthermore, positive shifts observed for the δb bands reinforce this statement. It is worth noting that the observed shifts are more intense to Sn(II) adducts than to Cd(II), which is probably due to the higher acidity of Sn(II) (larger nuclear effective charge: 5.65 for Sn and 4.35 for Cd). It is verified that the symmetrical N-H bands are more sensitive to this acidity difference since a positive shift is observed for Cd(II) adducts, whereas a negative shift of this band is verified to Sn(II) adducts.

In case of 4amp approximation, the same general orientation is observed for asymmetric and symmetric N-H bands. This fact indicates that in this case, NH2 is involved to a slight degree in the metallic coordination. This hypothesis is reinforced by the fact that for 4amp, the ringed breathing bands exhibit a negative shift (compared to free chelates and synthesized solid adducts), whereas positive shifts are observed in 3amp. Therefore, for 4amp adducts, the two “isolated” nitrogen atoms are the main coordination sites. Suggested coordination modes for 3amp and 4amp molecules are shown schematically in Figure 2.

Figure 2.

Figure 2

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Schematic representation of the suggested coordinative characteristics for (a) 3amt and (b) 4amt adducts.

As explicatory examples, the infrared spectra of 3amt solid adducts are shown in Figure 3.

Figure 3.

Figure 3

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Infrared spectra for (a) CdCl2-(3amt), (b) CdCl2-2(3amt), (c) SnCl2-(3amt).H2O, and (d) SnCl2-2(3amt).H2O.

In case of 2mct adducts, positive shifts of the νC = N band are observed for Sn(II) adducts, whereas negative shifts are verified to Cd(II) adducts. Such fact suggests a coordination through nitrogen to Sn(II) and a coordination through sulfur to Cd(II) in agreement with the fact that the nitrogen atom is a hard base and that Sn(II) is a harder acid than Cd(II).

For 2mcp adducts, the negative shifts observed for the ν(C-S); C-SH and ν(C=N) aromatic bands suggest that, in this case, both coordination sites N and S are involved in the coordination process for both cations considered.

The data of thermogravimetric curves for the 16 solid adducts are demonstrated in Figure 4. The main TG data are elucidated in Table 6.

Figure 4.

Figure 4

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Thermogravimetric curves for the 16 solid adducts.

Table 6.

TG data summary for Sn(II) and Cd(II) adducts with 3amt, 4amt, 2mcp, and 2mcp.

Adduct Step t i (°C) Degradation tf (°C) Process onset (°C) Mass loss (%)
SnCl2.(3amt).H2O 1 55 382 238 26.7
2 385 560 473 35.5
SnCl2.2(3amt).H2O 1 45 102 76 5.1
2 160 445 320 40.0
3 447 606 517 27.2
CdCl2.(3amt) 1 280 331 307 53.7
2 332 406 348 12.8
3 478 660 569 29.3
CdCl2.2(3amt) 1 188 271 234 24.1
2 348 448 401 16.8
3 449 681 587 43.0
SnCl2.(2mct).0.5H2O 1 31.4 83 50 3.3
2 127 344 237 43.2
3 346 461 404 7.5
4 462 615 513 6.2
SnCl2.2(2mct) 1 120 260 204 44.0
2 261 341 288 10.2
3 342 430 378 4.7
4 431 595 513 8.9
5 596 656 607 1.1
CdCl2.(2mct) 1 181 276 223 30.2
2 497 650 583 41.3
CdCl2.2(2mct).H2O 1 136 276 207 43.2
2 277 485 384 15.4
3 486 628 551 9.3
SnCl2.(2mcp).1.5H2O 1 110 199 154 8.0
2 200 355 285 55.4
3 421 654 534 3.1
SnCl2.2(2mcp).4H2O 1 103 221 154 14.3
2 222 349 302 82.1
3 584 670 585 1.8
CdCl2.(2mcp) 1 186 309 244 23.3
2 310 459 391 12.6
3 460 647 576 47.0
4 648 751 675 8.6
CdCl2.2(2mcp) 1 139 274 215 35.8
2 276 349 301 5.2
3 351 482 399 10.1
4 483 649 572 26.9
SnCl2.(4amt).4H2O 1 46 145 110 2.8
2 210 299 269 15.7
3 300 425 355 37.0
4 428 616 515 10.2
SnCl2.2(4amt).1.5H2O 1 63 191 133 6.8
2 192 319 257 39.2
3 320 407 358 18.2
4 497 619 545 14.2
CdCl2.(4amt).H2O 1 88 176 123 6.7
2 274 381 328 21.1
3 382 459 407 7.9
4 460 655 583 51.3
CdCl2.2(4amt) 1 195 289 256 17.9
2 290 390 324 23.7
3 392 456 420 4.8
4 457 679 583 47.5
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t i and tf are the initial and final temperatures of the thermal degradation process, respectively.

For each TG curve, the experimental mass losses (±5%) are similar to the proposed formulas. It is possible to verify that for all hydrated compounds, the first mass loss step is associated with the release of water molecules followed by the release of ligand molecules and sublimation of the metal chloride. Furthermore, it is verified that, considering only the release of ligand molecules (3amp, 4amp, 2mct, or 2mcp), the cadmium adducts are always more stable than the correspondent tin adducts. Since the infrared data suggest that the metal-to-ligand interaction is higher for tin adducts, this last result is an expected one, unless we take into account that the cadmium adducts generally polymerize [22–27] and so there is, probably for these compounds, the formation of cross-linking bonds, leading to more stable compounds, from a thermal point of view.

The antimicrobial effect of the adducts was measured against a variety of microorganisms including bacteria and fungus (Table 7 and Figure 5). The no-growth zones around the hole indicated the inhibiting activity of the adducts on the microbe. These were calculated and compared with the ampicillin as an antibacterial agent or amphotericin B as an antifungal agent. The adduct CdCl2.2(2mct).H2O and CdCl2.(2mct) showed the highest antimicrobial activities followed by SnCl2.(2mcp).1.5H2O among all other adducts. On other hand, the CdCl2.(3amt) and CdCl2.(4amt).H2O have no effect on any bacteria or fungal strains (Table 7). The antimicrobial activities of these adducts might be caused by a direct interaction of Cd (II) or Sn (II) ions with proteins, enzymes, nucleic acids, and membranes of microbe cells.

Table 7.

Antimicrobial activities (inhibition zone diameter, mm/µg sample) of papaverine and its metal complexes against Gram-positive bacteria, Gram-negative bacteria, and two types of fungi.

The adducts Gram-negative bacteria Gram-positive bacteria Fungi
E. coli P. aeruginosa B. subtilis S. aureus A. flavus C. albicans
Control: DMSO 0.0 0.0 0.0 0.0 0.0 0.0
Ampicillin (Antibacterial agent) 22 17 20 18 0.0 0.0
Amphotericin B (Antifungal agent) 0.0 0.0 0.0 0.0 17 19
SnCl2.(3amt).H2O 10 10 12 11 0.0 23
SnCl2.2(3amt).H2O 15 13 13 15 0.0 14
CdCl2.(3amt) 0.0 0.0 0.0 0.0 0.0 0.0
CdCl2.2(3amt) 12 12 12 15 0.0 11
SnCl2.(2mct).0.5H2O 9 0.0 10 10 0.0 0.0
SnCl2.2(2mct) 9 9 9 21 0.0 0.0
CdCl2.(2mct) 16 15 14 20 14 17
CdCl2.2(2mct).H2O 26 28 26 32 31 35
SnCl2.(2mcp).1.5H2O 16 15 16 21 0.0 9
SnCl2.2(2mcp).4H2O 13 14 14 14 0.0 0.0
CdCl2.(2mcp) 11 10 11 10 0.0 16
CdCl2.2(2mcp) 14 13 12 16 0.0 13
SnCl2.(4amt).4H2O 9 0.0 0.0 0.0 0.0 0.0
SnCl2.2(4amt).1.5H2O 10 9 12 13 0.0 9
CdCl2.(4amt).H2O 0.0 0.0 0.0 0.0 0.0 0.0
CdCl2.2(4amt) 9 0.0 0.0 9 0.0 0.0
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Figure 5.

Figure 5

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The antimicrobial effects of the 16 solid adducts. The number above the column indicates the inhibition zone diameter.

4. Conclusion

The adducts SnCl2.(3amt).H2O, SnCl2.2(3amt).H2O, CdCl2.(3amt), CdCl2.2(3amt), SnCl2.(2mct).0.5H2O, SnCl2.2(2mct), CdCl2.(2mct), CdCl2.2(2mct).H2O, SnCl2.(2mcp).1.5H2O, SnCl2.2(2mcp).4H2O, CdCl2.(2mcp), CdCl2.2(2mcp), SnCl2.(4amt).4H2O, SnCl2.2(4amt).1.5H2O, CdCl2.(4amt).H2O, and CdCl2.2(4amt)—where 3amt = 3-amino-1,2,4-triazole; 4amt = 4-amino-1,2,4-triazole; 2mct = 2-mercaptothiazoline; and 2mcp = 2-mercaptopyridine—were synthesized by a solid-state route and characterized by CHN elemental analysis and infrared spectroscopy. A thermogravimetric study was also performed. It is verified that, for all compounds, the monoadducts are the most stable ones. Such fact agrees with a higher ionic and covalent character of the metal-ligand bond for such compounds. From the result, it can be concluded that 14 of the 16 compounds have a good biological activity against these microorganisms.

Acknowledgments

The authors are grateful to Taif University for supplying essential facilities and acknowledge the support of Taif University Researchers Supporting Project (TURSP-2020/39), Taif University, Taif, Saudi Arabia.

Data Availability

The data used to support the findings of this study are included within the article.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  • 1.Almajan G. L., Barbuceanu S.-F., Bancescu G., Saramet I., Draghici C. Synthesis and antimicrobial evaluation of some fused heterocyclic [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole derivatives. European Journal of Medicinal Chemistry. 2010;45(12):6139–6146. doi: 10.1016/j.ejmech.2010.10.007. [DOI] [PubMed] [Google Scholar]
  • 2.Demirbas A., Sahin D., Demirbas N., Karaoglu S. A. Synthesis of some new 1,3,4-thiadiazol-2-ylmethyl-1,2,4-triazole derivatives and investigation of their antimicrobial activities. European Journal of Medicinal Chemistry. 2009;44(7):2896–2903. doi: 10.1016/j.ejmech.2008.12.005. [DOI] [PubMed] [Google Scholar]
  • 3.Imkan I. A., Ullah S., Imran M., et al. Synthesis of biocompatible triazole based non-ionic surfactant and its vesicular drug delivery investigation. Chemistry and Physics of Lipids. 2020;228 doi: 10.1016/j.chemphyslip.2020.104894.104894 [DOI] [PubMed] [Google Scholar]
  • 4.Yadav S. K., Yadav R. K., Yadava U. Computational investigations and molecular dynamics simulations envisioned for potent antioxidant and anticancer drugs using indole-chalcone-triazole hybrids. DNA Repair. 2020;86 doi: 10.1016/j.dnarep.2019.102765.102765 [DOI] [PubMed] [Google Scholar]
  • 5.Xu Z. 1,2,3-Triazole-containing hybrids with potential antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) European Journal of Medicinal Chemistry. 2020;206 doi: 10.1016/j.ejmech.2020.112686.112686 [DOI] [PubMed] [Google Scholar]
  • 6.Gao F., Wang T., Xiao J., Huang G. Antibacterial activity study of 1,2,4-triazole derivatives. European Journal of Medicinal Chemistry. 2019;173:274–281. doi: 10.1016/j.ejmech.2019.04.043. [DOI] [PubMed] [Google Scholar]
  • 7.Nuray G., Ömer K. Synthesis and antimicrobial activity evaluation of new 1,2,4-triazoles and 1,3,4-thiadiazoles bearing imidazo[2,1-b]thiazole moiety. European Journal of Medicinal Chemistry. 2010;45:63–68. doi: 10.1016/j.ejmech.2009.09.024. [DOI] [PubMed] [Google Scholar]
  • 8.İlkay E., Güniz Ş., Küçükgüzel S. R., Erik De C. Synthesis of some novel thiourea derivatives obtained from 5-[(4-aminophenoxy)methyl]-4-alkyl/aryl-2,4-dihydro-3H-1,2,4-triazole-3-thiones and evaluation as antiviral/anti-HIV and anti-tuberculosis agents. European Journal of Medicinal Chemistry. 2008;43:381–392. doi: 10.1016/j.ejmech.2007.04.010. [DOI] [PubMed] [Google Scholar]
  • 9.Ilkay S., Rollas S., Muammer K. Some 3-Thioxo/alkylthio-1,2,4-triazoles with a substituted thiourea moiety as possible antimycobacterials. Bioorganic & Medicinal Chemistry Letters. 2001;11:1703–1707. doi: 10.1016/s0960-894x(01)00283-9. [DOI] [PubMed] [Google Scholar]
  • 10.Charalabos A., Ana Ciric M. S., Panagiotis M. Z. Sulfonamide-1,2,4-thiadiazole derivatives as antifungal and antibacterial agents: synthesis, biological evaluation, lipophilicity, and conformational studies. Chemical and Pharmaceutical Bulletin. 2010;58:160–167. doi: 10.1248/cpb.58.160. [DOI] [PubMed] [Google Scholar]
  • 11.Imtiaz S., Shahid Hameed N. H. R., Muhammad A., Reaz Uddin Z., Ajmal Khan M. Synthesis, antioxidant activities and urease inhibition of some new 1,2,4-triazole and 1,3,4-thiadiazole derivatives. European Journal of Medicinal Chemistry. 2010;45:5200–5207. doi: 10.1016/j.ejmech.2010.08.034. [DOI] [PubMed] [Google Scholar]
  • 12.Rezki N., Almehmadi M. A., Ihmaid S., et al. Novel scaffold hopping of potent benzothiazole and isatin analogues linked to 1,2,3-triazole fragment that mimic quinazoline epidermal growth factor receptor inhibitors: synthesis, antitumor and mechanistic analyses. Bioorganic Chemistry. 2020;103 doi: 10.1016/j.bioorg.2020.104133.104133 [DOI] [PubMed] [Google Scholar]
  • 13.Harish S., Suroor A., Khan M. A. 1,3,4-Oxadiazole/thiadiazole and 1,2,4-triazole derivatives of biphenyl-4-yloxy acetic acid: synthesis and preliminary evaluation of biological properties. European Journal of Medicinal Chemistry. 2008;43:2688–2698. doi: 10.1016/j.ejmech.2008.01.039. [DOI] [PubMed] [Google Scholar]
  • 14.Samir F., Barsoum H. M., Marzouk A. A. Synthesis and anti-inflammatory activity of some pyrazole derivatives. Medicinal Chemistry Research. 2012;21:1722–1733. doi: 10.1007/s00044-011-9691-4. [DOI] [Google Scholar]
  • 15.Rajesh G., Jitendra Sainy S. C. Synthesis and biological evaluation of 2-amino-5-sulfanyl-1,3, 4-thiadiazole derivatives as antidepressant, anxiolytics and anticonvulsant agents. Medicinal Chemistry Research. 2011;20:245–253. doi: 10.1007/s00044-010-9308-3. [DOI] [Google Scholar]
  • 16.de Farias R. F., Nunes L. M., Airoldi C. Thermoanalytical study about histidine and cysteine-cadmium interactions. Journal of Thermal Analysis and Calorimetry. 2003;74(3):p. 923. doi: 10.1023/b:jtan.0000011024.89077.43. [DOI] [Google Scholar]
  • 17.de Farias R. F., da Silva A. O., da Silva U. G., Jr. Synthesis, characterization and TG-DSC study of cadmium halides adducts with caffeine. Thermochimica Acta. 2003;406(1-2):p. 245. doi: 10.1016/s0040-6031(03)00229-6. [DOI] [Google Scholar]
  • 18.de Farias R. F., Martinez L., Airoldi C. Synthesis, characterization and a thermogravimetric study of copper, cobalt and tin mono- and bis-adducts with ethyleneurea, ethylenethiourea and propyleneurea. Transition Metal Chemistry. 2002;27:p. 748. [Google Scholar]
  • 19.Martinez L., de Farias R. F., Airoldi C. Thermochemical data on adducts of copper chloride with the amino acids lysine and glycine. Thermochimica Acta. 2002;395:p. 21. doi: 10.1016/s0040-6031(02)00181-8. [DOI] [Google Scholar]
  • 20.de Farias R. F., Airoldi C., Scatena H., Jr. Empirical correlations involving calorimetric, thermogravimetric and infrared data for zinc halides adducts. Polyhedron. 2002;21(17):p. 1677. doi: 10.1016/s0277-5387(02)00982-8. [DOI] [Google Scholar]
  • 21.Gaber A., Alsanie W. F., Kumar D. N., Refat M. S., Saied E. M. Novel papaverine metal complexes with potential anticancer activities. Molecules. 2020;25(22):p. 5447. doi: 10.3390/molecules25225447. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 22.Machado M. O., de Farias R. F., Airoldi C. Two different synthetic routes involving the reaction of dodecylamine or nicotinamide with crystalline lamellar vanadylphosphate. Journal of Physics and Chemistry of Solids. 2004;65(10):p. 1697. doi: 10.1016/j.jpcs.2004.04.008. [DOI] [Google Scholar]
  • 23.de Farias R. F., da Silva A. O. Nickel(II) and cerium(IV) ethyleneurea, ethylenethiourea and propyleneurea adducts. Transition Metal Chemistry. 2003;28:p. 21. [Google Scholar]
  • 24.de Farias R. F., Airoldi C. The first VOPO4·2H2O intercalation compound synthesized through a solid-state reaction at room temperature. Journal of Solid State Chemistry. 2002;166(2):p. 277. doi: 10.1006/jssc.2002.9576. [DOI] [Google Scholar]
  • 25.de Farias R. F., Airoldi C. Calorimetric study of the adducts CdBr2·nL (n = 1 and 2; L = ethyleneurea and propyleneurea) Thermochimica Acta. 2002;390(1-2):p. 213. doi: 10.1016/s0040-6031(02)00079-5. [DOI] [Google Scholar]
  • 26.Farias R. F., Petrucelli G. C., Airoldi C. Thermochemical data on adducts of cyclic ureas and copper chloride: the resemblance to biological systems. Thermochimica Acta. 2001;376(1):p. 1. doi: 10.1016/s0040-6031(01)00529-9. [DOI] [Google Scholar]
  • 27.Greenwood N. N., Earnshaw A. Chemistry of the Elements. Cambridge, UK: Butterworth-Heinemann; 1984. [Google Scholar]

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