title: Cytotoxic alkaloids from the flowers of Senna spectabilis.
abstract: Three new alkaloids, 3(R)-benzoyloxy-2(R)-methyl-6(R)-(11'-oxododecyl)-piperidine (3), 5-hydroxy-2-methyl-6-(11'-oxododecyl)-pyridine (4) and 5-hydroxy-2-methyl-6-(11'-oxododecyl)-pyridine N-oxide (5), together with a known alkaloid, (-)-cassine (1), were isolated from the flowers of Senna spectabilis. A derivative, N,O-diacetylcassine (2), was semisynthesized. Their structures and stereochemistry were established on the basis of spectroscopic analysis. Cytotoxic activity and brine shrimp lethality of these compounds were evaluated. Compounds 2, 3 and 5 exhibited cytoxicity against KB cell lines with IC50 values of 5.2, 3.7 and 2.0 microg/mL, respectively.
authors.affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Silpakorn University, Nakorn Prathom, Thailand. lawan@email.pharm.su.ac.th
authors.forename: Lawan
authors.initials: L
authors.lastname: Sriphong
authors.forename: Uthai
authors.initials: U
authors.lastname: Sotanaphun
authors.forename: Siripan
authors.initials: S
authors.lastname: Limsirichaikul
authors.forename: Penpan
authors.initials: P
authors.lastname: Wetwitayaklung
authors.forename: Chaiyo
authors.initials: C
authors.lastname: Chaichantipyuth
authors.forename: Sunibhond
authors.initials: S
authors.lastname: Pummangura
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D001156:Artemia / Q000187:drug effects; D045744:Cell Line, Tumor / Q000187:drug effects; D007887:Fabaceae; D035264:Flowers; D006801:Humans; D020128:Inhibitory Concentration 50; D007928:Lethal Dose 50; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D010936:Plant Extracts