| Abstract
| - The first syntheses of (−)-fumiquinazolines A, B, and I, which proceed in 14 steps from protectedtryptophan, anthranilic acid, leucine, and alanine in 7% overall yield, are described. Tricycle 30was formed by a palladium-catalyzed cyclization. Oxidation of 30a with saccharine-derivedoxaziridine 21 for fumiquinazolines A and B and oxidation of 30b with dimethyldioxirane forfumiquinazoline I selectively formed the appropriate imidazoindolone stereoisomers. Applicationof the Ganesan−Mazurkiewicz cyclization completed the syntheses. Efficient 14-step syntheses of(−)-fumiquinazolines C (7) and E (3) and a 15-step synthesis of (−)-fumiquinazoline H (8) usingFmocNHCH(CH2SePh)CO2H as a dehydroalanine precursor that spontaneously eliminated benzeneselenol without oxidation under the cyclization conditions are also reported. Model 86 forfiscalins A with the H and OH anti to each other has been prepared, but the procedure that workedfor the model failed with the fully functionalized side chain.
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