(7R,8S,10S,11R,12S)-7,8,12-Trihydroxy-6,6,10,11-tetramethyl-4-propyl-7,8,11,12-tetrahydro-6H,10H-dipyrano[2,3-f;2',3'-h]chromen-2-one AIDS-051628 AIDS051628 NSC683207