Theoretical descriptors for the correlation of aquatic toxicity of environmental pollutants by quantitative structure-toxicity relationships.

Quantitative structure-toxicity relationships were developed for the prediction of aqueous toxicities for Poecilia reticulata (guppy) using the CODESSA treatment. A two-parameter correlation was found for class 1 toxins with R(2) = 0.96, and a five-parameter correlation was found for class 2 toxins with R(2) = 0.92. A five-parameter correlation for class 3 toxins had R(2) = 0.85. The correlations for class 4 toxins were less satisfactory. All the descriptors utilized are calculated solely from the structures of the molecules, which makes it possible to predict unavailable or unknown toxins.

Correlation of the solubilities of gases and vapors in methanol and ethanol with their molecular structures.

Two four-parameter quantitative structure-property relations, with R2 = 0.95 and R2 = 0.97, respectively, gave good correlations for the solubilities of 87 gases and vapors in methanol and 61 in ethanol. All the descriptors used are derived solely from the structures of the molecules, making it possible to predict solubilities for unavailable or unknown compounds.