Selective Search Focusing on Retro-Synthetically Important Bonds in A Synthesis Design System

A new capability has been added to the synthesis design system SYNSUP [1]. The new module generates synthetic routes that focus on key-bonds. Key-bonds are selected according to their spatial relationships to chiral atoms and central atoms of functional groups. When the key-bonds cannot be formed by any reaction known to SYNSUP, then structure changes in the vicinity of the bonds are effected so that the key-bonds can be disconnected in a retro-synthetic pathway. We called the fashion “selective search”. Such structure changes were studied, using 27 reported total synthesis of 25 naturally occurring compounds. This kind of selective search has been shown to be useful and practical for relatively complicated molecules.