Pimecrolimus Impurity 1

Chemical Name: (4R,5R,7S,8R,9S,11S,13E,15R,17E,19R,20S,23R)-20-((E)-1-((1R,3R,4R)-4-Chloro-3-methoxycyclohexyl)prop-1-en-2-yl)-15-ethyl-4-hydroxy-7,9-dimethoxy-5,11,13,19-tetramethyl-21,28-dioxa-1-azatricyclo[21.3.1.14,8]octacosa-13,17-diene-2,3,16,22-tetraone