Tacrolimus Hydroxy Acid Impurity

Chemical Name: (3S,4R,5S,8R,12S,14S,15R,16S,18R,25aS,E)-8-allyl-5,15,19-trihydroxy-3-((E)-1-((1R,3R,4R)-4-hydroxy-3-methoxycyclohexyl)prop-1-en-2-yl)-14,16-dimethoxy-4,10,12,18-tetramethyl-1,7,20-trioxo-1,3,4,5,6,7,8,11,12,13,14,15,16,17,18,19,20,22,23,24,25,25a-docosahydropyrido[2,1-c][1]oxa[4]azacyclodocosine-19-carboxylic acid