Comparative QSAR in toxicology: examples from teratology and cancer chemotherapy of aniline mustards.

During the past 30 years, thousands of quantitative structure-activity relationships (QSAR) have been published for all sorts of chemicals acting on many forms of life or parts thereof (DNA, enzymes, organelles, etc.). Very little effort has been made to show the relationship among these equations. In this report, we discuss two examples, the toxicity of phenols to rats and the effect of aniline mustards on a variety of living systems, where the electronic effects in the QSAR can be correlated to QSAR from physical organic chemistry. This enables one to make better mechanistic deductions about the biological structure-activity relationships. From this, it is concluded that radicals formed from the phenols cause birth defects.