Stereoselective Synthesis of the Indole Alkaloids Nitrarine, Nitramidine, and Isomers. A Biomimetic Approach
摘要:
Starting from tryptamine and dimeric piperidine derivative 8, the synthesis of 4, an immediate precursor in the biosynthesis of the Nitraria alkaloids, was accomplished. Cyclization of this achiral intermediate in aqueous solution produced a mixture of natural nitramidine 17 and one of its stereoisomers. Stereoselective reductions of these iminium salts with several reductors produced nitrarine (1), isonitrarine (2), and two new isomeric Nitraria indole alkaloids.
Quinolizidine alkaloids are synthesized from glutarimide yields via a piperidine ring transformation that is based on the lupinine biosynthesis. A short enantioselective bispiperidine synthesis usingR-phenylglycinol as a chiral precursor is described.
Stereoselective Synthesis of the Indole Alkaloids Nitrarine, Nitramidine, and Isomers. A Biomimetic Approach
作者:Martin J. Wanner、Gerrit-Jan Koomen
DOI:10.1021/jo00103a048
日期:1994.12
Starting from tryptamine and dimeric piperidine derivative 8, the synthesis of 4, an immediate precursor in the biosynthesis of the Nitraria alkaloids, was accomplished. Cyclization of this achiral intermediate in aqueous solution produced a mixture of natural nitramidine 17 and one of its stereoisomers. Stereoselective reductions of these iminium salts with several reductors produced nitrarine (1), isonitrarine (2), and two new isomeric Nitraria indole alkaloids.