New paeonilactone-A adducts formed by anaerobic incubation of paeoniflorinwith Lactobacillus brevis in the presence of arylthiols

During the course of preparing anticonvulsant paeonimetabolin-I adducts, ne w paeonilactone-A adducts: 9-phenylthiopaeonilaetone-A, 9-(o-tolylthio)paeo nilactone-A, 9-(m-tolylthio)paeonilactone-A, 9-(p-tolylthio)paeonilactone-A and 9-(2-naphthylthio)paeonilactone-A, were obtained along with expected p aeonimetabolin-I adducts by anaerobic incubation of paeoniflorin from peony roots with Lactobacillus brevis in the presence of the aromatic thiols, ph enylthiol, o-tolylthiol, m-tolylthiol, p-tolylthiol and t-naphthylthiol. Th e structures of these compounds were determined by spectroscopic methods in cluding two dimensional (2D) NMR.