(3'R,4S,6'R,7'S,8'E,11'S,12'R)-7-chloro-7'-methoxy-11',12'-dimethyl-13',13'-dioxospiro(2,3-dihydro-1H-naphthalene-4,22'-20-oxa-13lambda6-thia-1,14-diazatetracyclo(14.7.2.03,6.019,24)pentacosa-8,16(25),17,19(24)-tetraene)-15'-one
(3'r,4s,6'r,7's,8'e,11's,12'r)-7-chloro-7'-methoxy-11',12'-dimethyl-13',13'-dioxospiro(2,3-dihydro-1h-naphthalene-4,22'-20-oxa-13lambda6-thia-1,14-diazatetracyclo(14.7.2.03,6.019,24)pentacosa-8,16(25),17,19(24)-tetraene)-15'-one