title: Chemical synthesis of 24-beta-D-galactopyranosides of bile acids: a new type of bile acid conjugates in human urine.
abstract: A method is reported for the preparation of the C-24 carboxyl-linked beta-D-galactopyranosides of lithocholic, deoxycholic, chenodeoxycholic, ursodeoxycholic, and cholic acids, two of which were recently identified as a novel type of the metabolites of bile acids excreted in human urine. Direct esterification (galactosidation) of the unprotected bile acids with 2,3,4,6-tetra-O-benzyl-D-galactopyranose in the presence of 2-chloro-1,3,5-trinitrobenzene as a coupling agent and subsequent hydrogenolysis of the resulting benzyloxy-protected bile acid 24-beta-D-galactopyranosides over 10% palladium on charcoal under atmospheric pressure afforded the title compounds. The structures of the bile acid acyl galactosides were confirmed by measuring several (1)H-(1)H and (1)H-(13)C shift correlated 2D NMR.
authors.affiliation: Department of Chemistry, College of Humanities and Sciences, Nihon University, Sakurajousui, Setagaya, Tokyo 156-8550, Japan.
authors.forename: Genta
authors.initials: G
authors.lastname: Kakiyama
authors.forename: Shinji
authors.initials: S
authors.lastname: Sadakiyo
authors.forename: Takashi
authors.initials: T
authors.lastname: Iida
authors.forename: Kumiko
authors.initials: K
authors.lastname: Mushiake
authors.forename: Takaaki
authors.initials: T
authors.lastname: Goto
authors.forename: Nariyasu
authors.initials: N
authors.lastname: Mano
authors.forename: Junichi
authors.initials: J
authors.lastname: Goto
authors.forename: Toshio
authors.initials: T
authors.lastname: Nambara
mesh_terms: D001647:Bile Acids and Salts / Q000138:chemical synthesis* / Q000652:urine*; D002635:Chenodeoxycholic Acid / Q000737:chemistry; D019826:Cholic Acid / Q000737:chemistry; D003840:Deoxycholic Acid / Q000737:chemistry; D005690:Galactose / Q000138:chemical synthesis* / Q000652:urine*; D006031:Glycosylation; D006801:Humans; D008095:Lithocholic Acid / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular; D014580:Ursodeoxycholic Acid / Q000737:chemistry
chemical_list: D001647:Bile Acids and Salts; D003840:Deoxycholic Acid; D002635:Chenodeoxycholic Acid; D008095:Lithocholic Acid; D014580:Ursodeoxycholic Acid; D019826:Cholic Acid; D005690:Galactose