title: Diastereomers of neopterin and biopterin in human urine.
abstract: A new pteridine compound, named umanopterin, was isolated from human urine both of cancer patients and non-cancer controls. The structure was confirmed to be 2-amino-4(3H)-oxo-6-[(1'R,2'R)-1',2',3'-trihydroxypropyl]pteridine , a diastereomer of neopterin. The amount of umanopterin relative to neopterin was about 10%, which was practically the same among the non-cancer controls and the patients of various cancers. A small amount of a threo diastereomer of biopterin, named orinapterin, was isolated from human urine for the first time. Its structure was shown to be 2-amino-4(3H)-oxo-6-[(1'S,2'S)-1',2'-dihydroxypropyl]pteridine. A non-enzymatic transformation of 7,8-dihydroneopterin and 7,8-dihydrobiopterin by a mechanism analogous to keto-enol tautomerism is postulated for the formation of umanopterin and orinapterin in human body.
authors.affiliation: Department of Pharmacology, Nagoya University School of Medicine, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ogiwara
authors.forename: T
authors.initials: T
authors.lastname: Nagatsu
authors.forename: R
authors.initials: R
authors.lastname: Teradaira
authors.forename: K
authors.initials: K
authors.lastname: Fujita
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
mesh_terms: D000107:Acetylation; D001708:Biopterins / Q000031:analogs & derivatives* / Q000737:chemistry / Q000652:urine*; D006528:Carcinoma, Hepatocellular / Q000652:urine; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000652:urine; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009369:Neoplasms / Q000652:urine*; D019798:Neopterin; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D001708:Biopterins; D019798:Neopterin