CLOGP program

The chromatographic parameters were compared with calculated H2O-u-octanol logP value (2.23) (by CLOGP program) (96JC(A)135). 

Volume 2 of "Exploring QSAR" by Hansch and Leo (1995) contains the most extensive hard-copy database of log Poct values — about 18,000 values for over 16,500 structures. Sangster (1989) has published log P measurements and offers a comparable computer database on diskettes. Several of the computerized calculation programs access a similar log Poct database. If values in other solvent/ water systems are needed, the MASTERFILE database can accompany the CLOGP program on VAX and UNIX systems and contains about 40,000 measured log P values in over 300 solvent systems in addition to about 10,000 measured values of pKa. 

MedChem Master file or ClogP program, Sabljic et al. 1995)... 

There are many theoretical expressions to estimate the partition coefficient besides Equation (3.100). The most commonly used one is the CLOGP program. CLOGP is a fragment method that can be expressed as ... 

The MedChem database [64] contains the largest publicly available collection of more than 60,000 measurements of log P and log P> values, and it is available as a commercial product from BioByte Inc. (http //www.biobyte.com). This database provided experimental support for the development of the CLOGP program [65,66]. The PHYSPROP database [14] of Syracuse Research Inc. provides experimental logP values for 13,058 compounds. This database is publicly available at http //esc.syrres.com/interkow/KowwinData.htm. 

The methodology of the CLOGP program is somewhat unique in that fragments are determined by the computer—not preset by the designer. As will become evident, this has advantages in how much valuable latent information ... 

For comparison, some simple correlations were obtained between biological activity and the octanol/water partition coefficients, as calculated by the CLOGP program of Leo (19). An example is seen in Figure 3, which shows an apparent parabolic relationship between the log(l/minimum dose for acute death) and log P. The two outlier structures may have poorly calculated log P values (the epoxide ring and the conjugated system are special features), or they may undergo special metabolic transformation. 

Hydrophobic log P values of compounds II and III were calculated with the CLOGP program (21). Those of compounds I and IV were obtained from the literature (22). 

We wish to thank Dr. N. Ohno and Dr. N. Matsuo of this company for their valuable discussions. We also express appreciation to Mr. H. Katsumi of this company for installing the CLOGP program. 

The authors express their gratitude to Dr. Al Leo, Pomona College Medicinal Chemistry Project, for his guidance in the interpretation of the correction factors used in the CLOGP program. 

CLOGP Program, Release 3.3. Pomona College Medicinal Chemistry Project, Seaver Chemistry Laboratory, Pomona College, Claremont, CA. March 1985. 

Nonadditivities of n-octanol/water partition coefficients [173] limit the applicability of the CLOGP program. There is experimental evidence that some polar compounds may not be as polar as expected from their chemical structures, due to a network of intramolecular hydrogen bonds [263]. 

The exact isomeric structure could not be defined by the name given In the study. Mowever, the log P calculation were performed on each isomer listed using the CLOGP program. 

In the log P calculation, the CLOGP program does not distinguish between para and ortho isomers. 

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