in contrast , 25-hydroxyvitamin d3 endoperoxides [ 25- ( oh ) d3 endoperoxides , 2a and 2a ' ] and their analogues fluorinated at the 24- or 26- and 27-positions were 2.5-10 times more potent than 25-hydroxyvitamin d3 ( 1a ) in spite of the absence of the conjugated triene structure typical of vitamin d compounds .
C0006657
25-hydroxyvitamin d3
C2713074
25