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What is XLOGP?


    The XLOGP method is developed by Dr. Renxiao Wang. It is an atom-additive method for calculating octanol/water partition coefficient (logP). It gives the logP value for a given compound by summing the contributions from component atoms and correction factors.

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    Here Ai is the occurrence of the ith atom type and Bj is the occurrence of the jth correction factor; ai is the contribution of the ith atom type and bj is the contribution of the jth correction factor. The coefficients are derived by multivariate regression of large number of organic compounds.

    Our original work on XLOGP is published on J. Chem. Inf. Comput. Sci. 1997, 37, 615-621. XLOGP v1.1 was released to the public in September, 1997. Since then, we have improved the XLOGP algorithm to version 2.0. In the current version, totally 90 atom types are used to classify carbon, nitrogen, oxygen, sulfur, phosphorus, and halogen atoms. Ten additional correction factors are also applied to deal with some special chemical structures. Compared to its previous version, XLOGP v2.0 is more robust and gives better statistical results. The comparison of various logP calculation procedures demonstrates that our method gives much better results than other atom-additive approaches and is at least comparable to some popular fragmental approaches like CLOGP. Because of the simple methodology, “missing fragment” problem does not occur to our method.

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Correlation between the calculated and the experimental logP values of 1853 organic compounds.
(n=1853, r = 0.973, s = 0.349)

    We have prepared a manuscript describing the algorithm of XLOGP v2.0 in detail and have submitted it to Perspectives in Drug Design and Discovery. It will be available to the users soon.

     Copyright of the XLOGP program belongs to the Institute of Physical Chemistry, Peking University.


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