title: Determination of (R)-xanthoanthrafil, a phosphodiesterase-5 inhibitor, in a dietary supplement promoted for sexual enhancement.
abstract: We describe here the first case of the finding of xanthoanthrafil, a phosphodiesterase-5 inhibitor, in a dietary supplement. A methanol extract of the supplement product was first analyzed by TLC and HPLC. The results indicated that the extract contained an unknown compound. The molecular weight of the compound was 389 and the accurate mass showed its elemental composition to be C(19)H(23)N(3)O(6). Combined with this data, NMR analysis revealed the planar structure of the unknown compound to be N-(3,4-dimethoxybenzyl)-2-(1-hydroxypropan-2-ylamino)-5-nitrobenzamide. The R-configuration of this compound had been synthesized as a phosphodiesterase-5 inhibitor, formerly reported as FR226807 by Fujisawa Pharmaceutical Co., Ltd. The absolute configuration of the isolated compound was estimated to have R-configuration by its optical rotation. Considering its general properties, this compound is renamed as (R)-xanthoanthrafil with the agreement of Astellas Pharma Inc. which is the successor of Fujisawa Pharmaceutical Co., Ltd. Quantitative analysis revealed that the content of (R)-xanthoanthrafil in the product was about 31 mg/capsule.
authors.affiliation: Kanagawa Prefectural Institute of Public Health, Chigasaki, Kanagawa, Japan. kumasaka.z3aa@pref.kanagawa.jp
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kumasaka
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kawahara
authors.forename: Kayo
authors.initials: K
authors.lastname: Doi
authors.forename: Takashi
authors.initials: T
authors.lastname: Kojima
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Goda
mesh_terms: D001549:Benzamides / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5 / Q000737:chemistry*; D019587:Dietary Supplements / Q000032:analysis*; D013287:Illicit Drugs / Q000032:analysis; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008958:Models, Molecular; D008968:Molecular Conformation; D010726:Phosphodiesterase Inhibitors / Q000032:analysis*
chemical_list: D001549:Benzamides; D013287:Illicit Drugs; D007202:Indicators and Reagents; D010726:Phosphodiesterase Inhibitors; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C527317:(R)-xanthoanthrafil