title: Conformation of tropolone ring in antileukemic tropoloisoquinoline alkaloids.
abstract: Conformational analysis of antileukemic tropoloisoquinoline alkaloids isolated from Cissampelos pareira was conducted by thermodynamic proton nuclear magnetic resonance (1H NMR) studies. The line-broadening of one of methoxy methyl signals can be explained by the tropolone ring-puckering process. Analysis by dynamical simulated annealing and modified neglect of differential overlap (MNDO) calculations also supported puckering of tropolone ring system.
authors.affiliation: Department of Pharmacognosy, Tokyo College of Pharmacy, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Morita
authors.forename: K
authors.initials: K
authors.lastname: Matsumoto
authors.forename: K
authors.initials: K
authors.lastname: Takeya
authors.forename: H
authors.initials: H
authors.lastname: Itokawa
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology; D007546:Isoquinolines / Q000737:chemistry* / Q000494:pharmacology; D007938:Leukemia / Q000188:drug therapy; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D014334:Tropolone / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D007546:Isoquinolines; D014334:Tropolone