The disposition of N-(4,6-dimethyl-2-pyrimidinyl)benzene[U-14C]sulfonamide in the rat.

Rats given a single oral dose of N-(4,6-dimethyl-2-pyrimidinyl)benzene[U-14C]sulfonamide (14C-DAS) excreted 64.2% of the 14C in the urine and 22.4% in the feces within 96 hr. Compounds accounting for 86% of the 14C in the 0-24-hr urine were isolated by a variety of chromatographic techniques and identified by IR, NMR, and MS analysis. Approximately 4% of the 14C in the urine was the parent compound. The structures of 14C-metabolites in the urine indicated that 14C-DAS was metabolized by at least three pathways which included: 1) hydroxylation and glucuronic acid conjugation at the 4-position of the benzene ring; 2) hydroxylation, and sulfate ester and glucuronic acid conjugation at the 5-position on the heterocyclic ring; and 3) hydroxylation and glucuronic acid conjugation of one methyl group on the heterocyclic ring.