title: 25-Hydroxyvitamin D3 26,23-lactone: a new in vivo metabolite of vitamin D.
abstract: A major vitamin D metabolite was isolated in pure form from the blood plasma of chicks either maintenance levels or large doses of vitamin D3. The isolation involved methanol-chloroform extraction and five column chromatographic procedures. The metabolite purification and elution position on these columns were followed by a competitive protein binding assay. The metabolite was identified, using high- and low-resolution mass spectrometry, 270-MHz proton nuclear magnetic resonance spectrometry, ultraviolet absorption spectrophotometry, Fourier transform infrared spectrophotometry, and specific chemical reactions, as 3 beta,-25-dihydroxy-9,10-seco-5,7,10(19)-cholestatrieno-26,23-lactone. The trivial names 25-hydroxyvitamin D3 26,23-lactone or calcidiol 26,23-lactone are suggested for this compound.
mesh_terms: D000818:Animals; D002645:Chickens; D002762:Cholecalciferol / Q000097:blood*; D006887:Hydroxycholecalciferols / Q000097:blood*; D007783:Lactones / Q000097:blood; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D013058:Mass Spectrometry; D013053:Spectrophotometry
chemical_list: D006887:Hydroxycholecalciferols; D007783:Lactones; D002762:Cholecalciferol