Fig. 5.

Phenylephrine synthesis. a–c Three routes are depicted for the synthesis of the phenylephrine from benzoate derivatives. Each route is color coded to differentiate the route by choice of precursor and overall conversion. In addition, the precursor and target molecules are colored to depict moiety translocation. Known reactions are indicated by solid lines while reactions suggested using reaction rules are denoted with dashed lines. Every hypothetical reaction step is indexed with a reaction rule id (see Table 2 for description). The structure for pyruvate (pyr), acetaldehyde (acald), acetate, carbon dioxide (CO₂), oxygen (O₂), hydrogen peroxide (H₂O₂), formate (fma), S-adenosyl-l-methionine (adm), S-adenosyl homocysteine (adh), ascorbic acid (asc), dehydroascorbic acid (dhasc), tetrahydrobiopterin (tdh), and 4a-hydroxytetrahydrobiopterin (dhb) are not shown for clarity purpose