Chemical constituents of Clausena excavata: isolation and structure elucidation of novel furanone-coumarins with inhibitory effects for tumor-promotion.
A study of the chemical constituents of the leaves of Clausena excavata cultivated in a greenhouse led to the isolation and identification of 10 new furanone-coumarins named clauslactones A (1), B (2), C (3), D (4), E (5), F (6), G (7), H (8), I (9), and J (10), together with a known carbazole, clauszoline M, and a coumarin, umbelliferone. The new coumarins contain a C(10) terpenoid side chain with a furanone (gamma-lactone) moiety. Further, in clauslactones A-D (1-4), the terpenoid side chain was shown to be linked to the 7,8-dioxygenated coumarin skeleton through a 1, 4-dioxane ring system. This is the first example of coumarins with these structural characteristics in nature. These furanone-coumarins were found to exhibit inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate-induced Epstein-Barr virus early antigen activation in Raji cells.
Ito
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Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468-8503, Japan.
Itoigawa
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M
Katsuno
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Omura
M
M
Tokuda
H
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Nishino
H
H
Furukawa
H
H
D016588:Anticarcinogenic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D015394:Molecular Structure; D019685:Rosales / Q000737:chemistry*; D013057:Spectrum Analysis
D016588:Anticarcinogenic Agents; D003374:Coumarins