摘要:

AbstractAn overview is presented of computer programs designed to assist the synthetic organic chemist. Reaction retrieval, reaction prediction, and synthesis design programs are discussed, the development of these systems is outlined, and their aims and possibilities are described. Brief accounts of some representative systems are given.

ISSN:0165-0513    

DOI:10.1002/recl.19921110601

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractSYNLIB (SYNthesis LIBrary) is an expert system which allows laboratory scientists to rapidly and interactively search databases of chemical reaction information. SYNLIB is fully supported on personal computer and RISC workstation platforms and requires minimal computer expertise on the part of the chemist. By encouraging hands‐on access to information, SYNLIB allows complex chemical synthesis concepts to be presented directly to the practicing laboratory scientist. SYNLIB searching enables the user to query chemical reaction knowledge bases for matches to combinations of structural and non‐structural chemical questions. We discuss the design considerations for expert systems specifically for chemists and present an analysis of the chemical‐reaction information available from the published literature. A search for the formation chemistry of functionalized α,β‐unsaturated ketones is used to illustrate the search strategies

ISSN:0165-0513    

DOI:10.1002/recl.19921110602

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractSome basic problems of contemporary computer‐assisted organic synthesis are briefly dealt with. The discussion (led from the point of view of computer science) mainly concerns the question of a solution space in organic synthesis and methods of artificial intelligence used to search it. Some features of systems assisting in organic synthesis, regarded as dedicated expert systems, are also commented on. An interactive strategy for development of an optimum synthetic tree is proposed. Finally, expected future trends in computer‐assisted organic synthesis and simulation (modeling) of organic reactions are briefly summari

ISSN:0165-0513    

DOI:10.1002/recl.19921110603

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractThe evolution of Computer‐Assisted Organic Synthesis (CAOS) is briefly reviewed. The underlying concepts and strategies of the various approaches to CAOS are compared. A status report is given on bilateral synthesis design. This requires selection of suitable starting materials from a list of available compounds according to structural features of the target by correlation of substructures, augmentation of the target molecule by co‐products to yield an Ensemble of Molecules (EM) that is isomeric to the starting EM and, finally, establishment of synthesis routes that lead from the starting EM to the target EM. Despite of its apparent complexity, bilateral CAOS is a promising approach because of its combinatorial advanta

ISSN:0165-0513    

DOI:10.1002/recl.19921110604

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractA series of computer methods is presented that elucidate relationships between the target molecule, precursors, and starting materials of a synthesis. Both retrosynthetic and synthetic searches are performed to find the most rewarding pathways for the synthesis of complex organic structures including their stereochemical features. A user interface has been developed that allows easy switching between the various search methods and the results can be presented graphically. A system for reaction prediction has been developed that can predict the course and products of organic reactions to various depth of chemical knowledge, from the generation of isomers, up to the calculation of absolute rate constants.

ISSN:0165-0513    

DOI:10.1002/recl.19921110605

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractWe describe the Sumitomo Chemical Company computer program, which designs synthetic routes for organic molecules, without consulting a user. There are only approximately 2500 reactions stored in the program. Significant advances in the automation of reaction input are presented. We also give some examples of synthetic routes proposed by the program, one being an enantiospecific and stereospecific route for the synthesis of the antibiotic chloramphenicol.

ISSN:0165-0513    

DOI:10.1002/recl.19921110606

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractComputer‐Assisted Organic Synthesis (CAOS) has become a common tool in synthesis pathway design. Many different approaches exist, each giving suggestions for the exploration of the synthetic space. Validation of the proposed solutions can be done both by using different programs and by experimental realization of the synthesis. To this end, a molecule of medium complexity, erythronolide B, has been used to make a three‐way comparison using results obtained by the program LHASA, in the laboratory, and by the program Lilith. The importance of using different sources in studying a synthesis pathway is discussed, with respect to achieving the best result from each approach. The high level of convergence in the syntheses proposed by the Lilith program is the most interesting characteristic of the program's results. Moreover, reproduction of the syntheses proposed by the other approaches guarantees the applicability of the Lilith program to real synthetic problems. A brief outline of the Lilith program is inclu

ISSN:0165-0513    

DOI:10.1002/recl.19921110607

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractA novel scheme for assigning initial, or substrate‐independent, ratings for transforms (retroreactions) in the chemical knowledge base for the LHASA program for computer‐assisted synthetic analysis is described. The new rating scheme is based on keyword scales defined for eight rating criteria. Initial ratings are calculated as weighted averages of the ratings in the eight categories. Various applications of initial ratings in LHASA are outli

ISSN:0165-0513    

DOI:10.1002/recl.19921110608

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractOne of the strategies used by chemists when designing retrosynthetic routes is to direct them towards particular starting materials which have been chosen because they have structural similarities to the target compounds. This paper illustrates uses of the starting‐material strategy in the LHASA program. To apply the strategy, LHASA must be able to select potential starting materials, perceive how they map onto the target compound, recognise the structural changes implied by the mapping if the target structure is to be converted retrosynthetically into that of the starting material, find chemical reactions that can bring about the changes and decide upon the order in which they should be don

ISSN:0165-0513    

DOI:10.1002/recl.19921110609

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractA new approach of computer‐assisted design of organic synthesis is proposed with the COSYMA system. It is based on the similarity between the target molecule and an intermediate or the final product of a well‐known synthesis pathway. Similarity between two molecules is defined as equality of the structures obtained by applying generalization rules to these two molecules. Similarity criteria are described, and associated generalization rules expressed. A new internal representation of synthesis pathways is also described, which fits COSYMA requirements, and consists of time‐independent structural and temporal parts. The temporal part describes variations of atom connectivity in the different synthesis

ISSN:0165-0513    

DOI:10.1002/recl.19921110610

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY