7,15,23-Trimethyl-3,11,19-trioxatetracyclo[19.3.1.1~5,9~.1~13,17~]heptacosa-1(25),5(27),6,8,13(26),14,16,21,23-nonaene-25,26,27-triol AIDS-153491 AIDS153491 NSC700321