TY - JOUR T1 - IDENTIFICATION OF A RARE SULFONIC ACID METABOLITE OF ANDROGRAPHOLIDE IN RATS JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 983 LP - 985 DO - 10.1124/dmd.31.8.983 VL - 31 IS - 8 AU - Xiangjiu He AU - Jiankuan Li AU - Hao Gao AU - Feng Qiu AU - Ke Hu AU - Xiangmin Cui AU - Xinsheng Yao Y1 - 2003/08/01 UR - http://dmd.aspetjournals.org/content/31/8/983.abstract N2 - Andrographolide is widely used in clinic as an anti-inflammatory and antibiotic drug. In this paper, the metabolites of andrographolide in rats after single oral doses of 120 mg/kg were investigated. The structures of the metabolites were elucidated by high-resolution mass spectra, NMR spectroscopy including 1H NMR, 13C NMR, and two-dimensional NMR, through comparison to a synthetic standard. The main metabolite of andrographolide in rats was 14-deoxy-12(R)-sulfo andrographolide. In the proposed mechanism, the β-carbon of α, β-unsaturated carbonyl was attacked by sulfonic acid, to form the sulfonate compound. This was a rare metabolic reaction. It may be the main metabolic pathway of andrographolide in rats. The polarity of the sulfonate metabolite increased greatly and could be easily eliminated from body. The American Society for Pharmacology and Experimental Therapeutics ER -