Synonyms: 15,19-Epoxy-3H-pyrido[2,1-c][1,4]oxaazacyclotricosine-1,7,20,21(4H,23H)-tetrone,8-ethyl-5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a-hexadecahydro-5,19-dihydroxy-3-[2-(4-hydroxy-3-methoxycyclohexyl)-1-methylethenyl]-14,16-dimethoxy-4,10,12,18-tetramethyl-,[3S-[3R*[E(1S*,3S*,4S*)],4S*,5R*,8S*,9E,12R*,14R*,15S*,16R*,18S*,19S*,26aR*]]-;Immunomycin;Changchuanmycin;FK 520;FR 520;FR 900520;(3S,4R,5S,8R,12S,14S,15R,16S,18R,19R,26aS)-8-Ethyl-5,19-dihydroxy-3-{(E)-2-[(1R,3R,4R)-4-hydroxy-3-methoxycyclohexyl]-1-methylethenyl}-14,16-dimethoxy-4,10,12,18-tetramethyl-5,6,8,11,12,13,14,15,16,17 ,18,19,24,25,26,26a-hexadecahydro-3H-15,19-epoxypyrido[2,1-c][1,4]oxazacyclotricosine-1,7,20,21(4H,23H)-tetrone;L 683590;