Total Synthesis of (−)-Fumiquinazolines A, B, C, E, H, and I. Approaches to the Synthesis of Fiscalin A
- 19 December 2002
- journal article
- Published by American Chemical Society (ACS) in The Journal of Organic Chemistry
- Vol. 68 (2) , 545-563
- https://doi.org/10.1021/jo0264980
Abstract
The first syntheses of (−)-fumiquinazolines A, B, and I, which proceed in 14 steps from protected tryptophan, anthranilic acid, leucine, and alanine in 7% overall yield, are described. Tricycle 30 was formed by a palladium-catalyzed cyclization. Oxidation of 30a with saccharine-derived oxaziridine 21 for fumiquinazolines A and B and oxidation of 30b with dimethyldioxirane for fumiquinazoline I selectively formed the appropriate imidazoindolone stereoisomers. Application of 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) using FmocNHCH(CH2SePh)CO2H as a dehydroalanine precursor that spontaneously eliminated benzeneselenol without oxidation under the cyclization conditions are also reported. Model 86 for fiscalins A with the H and OH anti to each other has been prepared, but the procedure that worked for the model failed with the fully functionalized side chain.Keywords
This publication has 20 references indexed in Scilit:
- Facile Chemoselective Synthesis of Dehydroalanine-Containing PeptidesOrganic Letters, 2000
- Substrate-directable chemical reactionsChemical Reviews, 1993
- Heterolysis, homolysis, and cleavage energies for the cation radicals of some carbon-sulfur bondsJournal of the American Chemical Society, 1992
- Hydroxylation of 5H-3-Oxo-2,3,6,7,8,9-hexahydroimidazo[1,2-a]azepine derivatives by molecular oxygenJournal of Heterocyclic Chemistry, 1990
- Silafunctional compounds in organic synthesis. 46. Platinum-catalyzed intramolecular hydrosilation of allylamines: formation of 1-aza-2-silacyclobutanes and application to stereoselective synthesis of 2-amino alcoholsThe Journal of Organic Chemistry, 1990
- Cephalotaxine analogs: stereospecific synthesis of spiro-fused 3-benzazepine and 1,3-benzodiazepine derivativesThe Journal of Organic Chemistry, 1990
- AMINE BORANES AS SELECTIVE REDUCING AND HYDROBORATING AGENTS. A REVIEWOrganic Preparations and Procedures International, 1984
- Total synthesis of (+)- and (-)-tryptoquivaline G by biomimetic double cyclizationJournal of the American Chemical Society, 1983
- General acid catalysis in the hydrolysis of benzo[a]pyrene 7,8-diol 9,10-epoxidesJournal of the American Chemical Society, 1979
- SYNTHESIS OF SUBSTITUTED INDOLES VIA INDOLINESRussian Chemical Reviews, 1967