Abstract
(23S)-23,25-Dihydroxycholecalciferol was converted into at least 5 metabolites in kidney homogenates prepared from 1,25-dihydroxycholecalciferol-treated chickens. One of these was positively identified as 23,25,26-trihydroxycholecalciferol by UV-absorbance analysis, mass spectrometry and chemical formation of derivatives. 23,25,26-Trihydroxycholecalciferol produces 25-hydroxycholecalciferol-26,23-lactone when incubated in chick kidney homogenates.