1,10-Dioxa-4,7,13,16-tetraazacyclooctadecane-2,5,8,11,14,17-hexone, 4,13-dimethyl-6,15-bis[(1R)-1-methylpropyl]-9,18-bis(phenylmethyl)-, (6S,9R,15S,18R)- AIDS-220654 AIDS220654 Hirsutellide A