135635-47-1

31-O-demethyl-FK506 Tacrolimus Impurity 37 Tacrolimus Impurity 40 31-O-Demethyltacrolimus 15,19-Epoxy-3H-pyrido[2,1-c][1,4]oxaazacyclotricosine-1,7,20,21(4H,23H)-tetrone, 3-[2-(3,4-dihydroxycyclohexyl)-1-methylethenyl]-5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a-hexadecahydro-5,19-dihydroxy-14,16-dimethoxy-4,10,12,18-tetramethyl-8-(2-propen-1-yl)-