title: 3,3',5'-Tri-O-methylpiceatannol and 4,3',5'-tri-O-methylpiceatannol: improvements over piceatannol in bioactivity.
abstract: Piceatannol (3,4,3',5'-tetrahydroxy-trans-stilbene) (NSC 365798) has recently been isolated and was subsequently synthesized for NCI tumor panel testing as a new antileukemic natural product from the seeds of Euphorbia lagascae. During the synthesis, a bioactive reaction mixture of several partially O-methylated piceatannol analogues was obtained. This mixture has now been maximized and subjected to bioactivity-directed fractionation, using brine shrimp lethality, to yield 3,3',5'-tri-O-methylpiceatannol (NSC 381281); this new compound has improved stability and better bioactivity in several systems than piceatannol itself. To confirm the structure, 5 was synthesized from vanillin. In addition, the isovanillin analogue, 4,3',5'-tri-O-methylpiceatannol (NSC 381864), another new compound, was synthesized and found to be bioactive.
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000138:chemical synthesis*; D002460:Cell Line; D007942:Leukemia, Experimental / Q000188:drug therapy; D051379:Mice; D013267:Stilbenes / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D013267:Stilbenes; C053117:3,3',5'-tri-O-methylpiceatannol; C053118:4,3',5'-tri-O-methylpiceatannol; C041525:3,3',4,5'-tetrahydroxystilbene