(-)-(trans)-2H,6H,12H-Benzo[1,2-b:3,4-b':5,6-b'']tripyran-2,12-dione, 10,11-dihydro-6,6,10,11-tetramethyl-4-propyl-, (10S,11S)- (-)-12-Oxocalanolide B 183904-54-3 2H,6H,12H-Benzo[1,2-b:3,4-b':5,6-b'']tripyran-2,12-dione, 10,11-dihydro-6,6,10,11-tetramethyl-4-propyl-, (10S-trans)- AIDS-033397 AIDS033397 Calanolide B deriv.