出版社：American Society for Biochemistry and Molecular Biology
摘要：The chemical structures of the three major bile acids present in the gallbladder bile of the Red-winged tinamou ( Rhynchotus rufescens ), an early evolving, ground-living bird related to ratites, were determined. Bile acids were isolated by preparative reversed-phase HPLC. Two of the compounds were identified as the taurine N -acylamidates of (25 R )-3α,7α-dihydroxy-5β-cholestan-27-oic acid (constituting 22% of biliary bile acids) and (25 R )-3α,7α,12α-trihydroxy-5β-cholestan-27-oic acid (constituting 51%). The remaining compound, constituting 21% of biliary bile acids, was an unknown C27 bile acid. Its structure was elucidated by LC/ESI-MS/MS and NMR and shown to be the taurine conjugate of (25 R )-1β,3α,7α-trihydroxy-5β-cholestan-27-oic acid, a C27 trihydroxy bile acid not previously reported. Although C27 bile acids with a 1β-hydroxyl group have been identified as trace bile acids in the alligator, this is the first report of a major biliary C27 bile acid possessing a 1β-hydroxyl group.
