Biologically active aspidofractinine alkaloids from Kopsia singapurensis.
Ten new indole alkaloids of the aspidofractinine type, in addition to several recently reported indole alkaloids and 20 other known alkaloids, were obtained from the leaf and stem-bark extract of the Malayan Kopsia singapurensis, viz., kopsimalines A-E (1-5), kopsinicine (6), kopsofinone (7), and kopsiloscines H-J (8-10). The structures of these alkaloids were determined using NMR and MS analysis. Kopsimalines A (1), B (2), C (3), D (4), and E (5) and kopsiloscine J (10) were found to reverse multidrug-resistance in vincristine-resistant KB cells, with 1 showing the highest potency.
Subramaniam
G
G
Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia.
Hiraku
Osamu
O
Hayashi
Masahiko
M
Koyano
Takashi
T
Komiyama
Kanki
K
Kam
Toh-Seok
TS
D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D029062:Apocynaceae / Q000737:chemistry*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D026121:Indole Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D007624:KB Cells; D008296:Malaysia; D015394:Molecular Structure; D024301:Plant Bark / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D014750:Vincristine / Q000494:pharmacology*
D000972:Antineoplastic Agents, Phytogenic; D026121:Indole Alkaloids; D014750:Vincristine