Ir-Catalyzed Reverse Prenylation of 3-Substituted Indoles: Total Synthesis of (+)-Aszonalenin and (−)-Brevicompanine B
摘要:
The selective reverse prenylation of 3-substituted-1H-indoles at C3 is described. The iridium-catalyzed reaction proceeds with high branched to linear selectivity (>20:1) for a variety of indoles. In addition, a diastereoselective reverse prenylation of tryptophan methyl ester is disclosed, and its synthetic utility is demonstrated in the synthesis of (+)-aszonalenin and (-)-brevicompanine B.
The biosynthesis of the mould metabolites roquefortine and aszonalenin from L-[2,4,5,6,7-2H5]Tryptophan
作者:Balkrishen Bhat、David M. Harrison、H. Maxine Lamont
DOI:10.1016/s0040-4020(01)81556-8
日期:1993.1
L-[2,4,5,6,7-2H5]Tryptophan was incorporated into roquefortine 2 by Penicillium roqueforti and aszonalenin 3 by Aspergillus zonatus with retention in each case of five deuterium atoms; that 5a-hydrogen of both metabolites is derived from the 2-hydrogen of tryptophan
Stereospecific synthesis of aszonalenins by using two recombinant prenyltransferases
作者:Wen-Bing Yin、Jun Cheng、Shu-Ming Li
DOI:10.1039/b902413a
日期:——
and its (S)-isomer (7). Interestingly, AnaPT and CdpNPT introduced prenyl moieties from opposite sides of the indoline ring system. This feature was successfully used for the chemoenzymatic synthesis of four aszonalenin stereoisomers by using 6 and 7 as substrates and AnaPT and CdpNPT as catalysts. The stereoselectivity of the one-step reactions was about 100% and the conversion rates reached 85–100%
The total synthesis of (−)-dihydroaszonalenin and the stereochemistry of aszonalenin
作者:Balkrishen Bhat、David M Harrison
DOI:10.1016/s0040-4039(00)85350-2
日期:1986.1
The enantiomer of dihydroaszonalenin has been synthesised from L-tryptophan; aszonalenin has been assigned the relative and absolute stereochemistry indicated.