.beta.-Guttiferin .beta.-Guttilactone 2-Butenoic acid, 2-methyl-4-[3a,4,5,7-tetrahydro-8-hydroxy-3,3,11-trimethyl-13-(3-methyl-2-butenyl)-11-(4-methyl-3-pentenyl)-7,15-dioxo-1,5-methano-1H,3H,11H-furo[3,4-g]pyrano[3,2-b]xanthen-1-yl]-, (2Z)- 2752-65-0 AIDS-151817 AIDS151817 Gambogic acid Guttic acid NSC693702