Route Designer, version 1.0, is a new retrosynthetic analysis package that generates complete synthetic routes for target molecules starting from readily available starting materials. Rules describing retrosynthetic transformations are automatically generated from reaction databases, which ensure that the rules can be easily updated to reflect the latest reaction literature. These rules are used to carry out an exhaustive retrosynthetic analysis of the target molecule, in which heuristics are used to mitigate the combinatorial explosion. Proposed routes are prioritized by an empirical rating algorithm to present a diverse profile of the most promising solutions. The program runs on a server with a web-based user interface. An overview of the system is presented together with examples that illustrate Route Designer's utility.

The discipline of retrosynthetic analysis is now just over 40 years old. From the earliest day, attempts were made to incorporate this approach into computer programs to test the extent in which chemical perception and synthetic thinking could be formalized. Despite pioneering research efforts, computer‐aided synthetic analysis failed to achieve widespread routine use by chemists, which can be attributed in part to the difficulty of building the required high‐quality retrosynthetic transform databases required for credible analyses. However, with the advent over the past 25 years of large comprehensive reaction databases, work on successfully automating the construction of reliable and comprehensive reaction rule databases is promising to revitalize research in this field. This review compares and contrasts the diverse approaches taken by selected programs in both the design and implementation of molecule feature perception and reaction rule representation, and we review the concepts of synthetic strategy selection, representation, and execution. In particular, we discuss the current work on automating the construction of reliable and comprehensive synthetic rule sets from available reaction databases in newer programs such as ARChem. We argue that the progress achieved in this aspect paves the way to a deeper exploration of computer approaches to applying strategy and control in the synthesis problem. © 2011 John Wiley & Sons, Ltd. This article is categorized under: Computer and Information Science > Chemoinformatics

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The transformational methodology described in this paper induces new knowledge, which may be open under any deductive process. The method of transposition is used to maintain a maximum size for the application as well as meta-rule bases. The "move to head" method is used by both the application and metarule bases for hypotheses formation. Whenever an application rule is fired, it is transposed on the transposition list and also moved to the head on the other list. If any meta-rule on a solution path individually leads to a contradiction on the application rule base, then the offending meta-rule is expunged. Then, when the system is idle enter dream mode, whereby rule i ⇒ rule j is generated by the 3-2-1 skewed twister as a candidate most-specific meta-rule. Candidate most-specific meta-rules are "cored" to create one generalization per candidate. These candidate meta-rules are tested for application to each rule in the application domain rule base. In order to be saved in the meta base, they may not map any existing rule in the application domain rule base to one having the same antecedent as another in this base, but a different consequent (as found by hashing). In addition, all candidate meta-rules must map at least one rule in the application base to another distinct one there, or be symmetrically induced from meta-rules that so map.