Structure-activity relationships ring transformations

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. 

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