STARTING MATERIAL ORIENTED RETROSYNTHETIC ANALYSIS IN THE LHASA PROGRAM .2. MAPPING THE SM AND TARGET STRUCTURES

This paper describes a method for matching two chemical structures in which the degree of similarity may be small. The combined use of iterative set division and a backtracking algorithm is described. Rapid identification of the largest areas of carbon skeleton common to the starting material and target structures is followed by a more rigorous analysis of the nonidentical areas to complete the atom-to-atom mapping of the structures.