PRECLAV

PRECLAV (PRoperty Evaluation by CLAss Variables) is a useful software for QSPR/QSAR calculations, available from Tarko Laszlo, Center of Organic Chemistry (CCO) - Bucharest, Romanian Academy.

Here are some key features of "PRECLAV":

· accepts as input MOPAC93 output files · analyzes molecules with maximum 99 atoms (H, C, N, O, S, P, F, Cl, Br, I, B, Si or As) · analyzes molecules with maximum 60 heavy atoms (C, N, O, S, P, F, Cl, Br, I, B, Si or As) · analyzes maximum 500 molecules (learning set + testing set) · calculates over 1100 (global, local and grid / field) descriptors · calculates the aromaticity of chemical bonds by the TPA algorithm · computes the optimum value for probe atom distances · selects descriptors using r2 and Class functions · computes weighting factors by the Ordinary Least Squares Method · QSPR /QSAR selection is made by r2 function and r2CV , rKCV cross-validation functions · minimum number of predictors in final QSPR /QSAR: 2 · maximum number of predictors in final QSPR /QSAR: 10 · adaptable to work with user databases

Limitations:

· may analyse only 50 molecule databases · none time limitations

What's New in This Release:

· accepts as input MOPAC93 output files · new molecular descriptors · work very easy with user database