title: Enantiomeric derivatives of tokinolide B: absolute configuration and biological properties.
abstract: The enantiomeric lactams (-)-8, (+)-8, (+)-9, and (-)-9 were formed by the reaction of the dimeric phthalide rac-tokinolide B (rac-3) with (R)-(+)-α-methylbenzylamine and (S)-(-)-α-methylbenzylamine. The absolute configurations of compounds 8 and 9 were assigned by experimental and theoretically calculated electronic circular dichroism methods for (+)-8 and (-)-9. Compounds 3, 5, (-)-8, (+)-8, (+)-9, and (-)-9 displayed cytotoxic activity toward several human tumor cell lines, with (-)-8 and (-)-9 being the most potent.
authors.affiliation: Instituto de Química de la  Universidad Nacional Autónoma de México , Circuito Exterior, Ciudad Universitaria, Coyoacán 04510, México, D.F.
authors.forename: Alejandra
authors.initials: A
authors.lastname: León
authors.forename: J Antonio
authors.initials: JA
authors.lastname: Cogordán
authors.forename: Olov
authors.initials: O
authors.lastname: Sterner
authors.forename: Guillermo
authors.initials: G
authors.lastname: Delgado
mesh_terms: D000465:Algorithms; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002942:Circular Dichroism; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020014:K562 Cells; D007769:Lactams / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D008962:Models, Theoretical; D019906:Nuclear Magnetic Resonance, Biomolecular; D010627:Phenethylamines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013237:Stereoisomerism
chemical_list: D000970:Antineoplastic Agents; D001572:Benzofurans; D007769:Lactams; D010627:Phenethylamines; C574260:tokinolide B; C033198:1-phenethylamine