The Computer as a Guide and Assistant in Retrosynthetic Analysis

Initially the idea of computer utilization in the practice of organic synthesis was advanced in Vleduts s publication in 1963. Yet the importance of studies in this area was recognized only after the famous work of Corey and Wipke published in 1969. Below we will examine some aspects of the methodology elaborated in the studies of this group. 

Let us consider the general principles of operation of the LHASA program in finding a synthetic pathway to polycyclic system. The program can be aimed by the chemist along two modes of search. The first mode of operation implies that 

As a check on the effectiveness of the LHASA program, the authors performed an analysis on 14 polycyclic compounds for which a synthesis was already reported in the literature. In 10 of these cases, the LHASA program included in the set of the generated solutions the very synthetic schemes that had been successfully realized. 

As demonstrated above, the most efficient reactions in the construction of cyclic structures are those that lead to the formation of several bonds as the result of a single chemical operation. This consideration stimulated the development of an alternative version of the LHASA programs aimed at finding ways of dismantling target structures with the help of especially effective disconnec- 

The process of retrosynthetic matching of a target structure into a sub-goal containing the conjugated cyclohexenone fragment (thus amenable to retro-Robinson annulation simplification) involves the utilization of a combination of 

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