(+/-)-Calanolide D (+/-)-Cis-ketone 12-Oxocalanolide 2H,6H,12H-Benzo[1,2-b:3,4-b':5,6-b'']tripyran-6,12-dione,10,11-dihydro-2,2,10,11-tetramethyl-8-propyl-, (10S,11R)- AIDS-064174 AIDS064174