LHASA analysis

In 1969 Corey and Wipke [7] reported the program OCSS (Organic Chemical Simulation of Synthesis) which was the precursor of one of the most powerful programs known at present which has been named LHASA (the acronym of Logic and Heuristics Applied to Synthetic Analysis) [5b] [8]. Since then, different... 

DfW predictions include information about the mechanism of activity, for example metabolic steps necessary for toxicity. For a more detailed analysis of the toxicity of a compound and its metabolites DfW can be used in combination with an in silico program for the prediction of metabolites. LHASA Limited offers such a program with the name METEOR. For the combination of these two systems, first the metabolites of a compound are predicted by METEOR. These metabolites are then sent to DfW for the prediction of toxicity of the compound and its predicted metabolites. 

The computer-assisted synthetic analysis designated OCSS (organic chemical simulation of synthesis) and LHASA (logic and heuristics applied to synthetic analysis) were designed to assist chemists in synthetic analysis by Corey et LHASA generates trees of synthetic intermediates from a target molecule by analysis in the retrosynthetic direction. 

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. 

Series 61, American Chemical Society, Washington, DC, 1977, pp. 1-32. LHASA—Logic and Heuristics Applied to Synthetic Analysis. 

Analysis of diffraction data to be collected by area detectors. Silicon Graphics. LHASA... 

Retrosynthetic Analysis. An approach to computer-assisted synthesis design that starts with the products of a reaction or sequence of reactions and works backwards toward the reactants. An example program that implements retrosynthetic analysis is the LHASA program of E. J. Corey s group. 

Corey and Feiner have developed a computer program (LHASA) for conformational analysis and for determining the destabilization energies (Ep) in substituted cyclohexane derivatives. In the following discussion, we will adopt their A, G and U designations and use the corresponding values for evaluating steric interactions. 

Socorro et al, 2005) and the LHASA (Logic and Henristics Applied to Synthetic Analysis) software (see URL). However, the cnrrent solntions to chemical reaction prediction have several limitations. Secondary and tertiary interactions are rarely considered and there is httle work on chemistry reasoning which is valrrable for chemical stability analysis bnt would reqtrire an exphcit irrformation model. In additiorr, there is little scope for integration of the reaction irrformation (which might describe conditions in microsolutiorts found between solid particles) with the solid information. 

Logic and Heuristics Applied to Synthetic Analysis (LHASA) is an expert system for synthesis planning that assists chemists in designing efficient routes to target molecules for organic synthesis. 

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