Manuifolin Q, an unusual 4-aryl-substituted isoflavan from Maackia tenuifolia.

Manuifolin Q (1), an unusual 4-aryl-substituted isoflavan, was isolated from the roots of Maackia tenuifolia. Its absolute configuration was determined as (3R,4R)-3,4-trans-7,2'-dihydroxy-4'-methoxy-4-[(2,4-dihydroxy-5-(1,1-dimethyl-2-propenyl)]-phenyl-isoflavan, on the basis of spectroscopic analysis.

Identification of three sulfate-conjugated metabolites of berberine chloride in healthy volunteers' urine after oral administration.

AIM: To identify the structure of unknown metabolites of berberine (Ber) in human urine after oral administration. METHODS: Urine samples were obtained from 5 volunteers after they orally took Ber chloride 0.9 g per day for three days. Metabolites in urine samples were isolated and purified by polyporous resin column chromatography. The individual metabolites were identified mainly using electrospray ionization mass spectroscopy (ESI-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy. RESULTS: Three unknown metabolites (M1, M2, and M3) were isolated. They were susceptible to arylsufatase. ESI-MS measurements of M1, M2, and M3 produced quasimolecular ions [M+H]+, m/z 17.9, 404.0, and 402.0 respectively. Especially, each of them produced a characteristic protonated ion [M-80+H]+, which can be ascribed as quasimolecular ions lost a SO3 fragment. 1H NMR spectra of the metabolites were also obtained and each of 1H signals was assigned. CONCLUSION: Structures of M1, M2, and M3 were firmly identified as jatrorrhizine-3-sulfate, demethyleneberberine-2-sulfate, and thalifendine-10-sulfate, and the major metabolite was M2.