Biologically active aspidofractinine, rhazinilam, akuammiline, and vincorine alkaloids from Kopsia.
Eleven new indole alkaloids, in addition to the previously reported rhazinal (1), and 14 other known alkaloids, were obtained from the Malayan Kopsia singapurensis, viz., kopsiloscines A-F (2-7), 16-epikopsinine (8), kopsilongine- N-oxide (9), 16-epiakuammiline (10), aspidophylline A (11), and vincophylline (12). The structures of these alkaloids were determined using NMR and MS analyses. Rhazinal (1), rhazinilam (17), and rhazinicine (18) showed appreciable cytotoxicity toward drug-sensitive as well as vincristine-resistant KB cells, while kopsiloscines A (2), B (3), and D (5) and aspidophylline A (11) were found to reverse drug-resistance in drug-resistant KB cells.
Subramaniam
G
G
Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Hiraku
Osamu
O
Hayashi
Masahiko
M
Koyano
Takashi
T
Komiyama
Kanki
K
Kam
Toh-Seok
TS
D000470:Alkaloids / Q000737:chemistry / Q000145:classification / Q000302:isolation & purification* / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D018432:Drug Resistance, Multiple / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D007212:Indolizines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D007624:KB Cells; D007769:Lactams / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D008296:Malaysia; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry*
D000470:Alkaloids; D000972:Antineoplastic Agents, Phytogenic; D007212:Indolizines; D007769:Lactams; C009170:rhazinilam