U. Schmidt, M. Kroner, H. Grieser
Apr 10, 1990
Citations
0
Influential Citations
15
Citations
Journal
ChemInform
Abstract
(2S,3S)-2-Acetoxy-3-methylvaleric acid is prepared from L-isoleucine with 96% retention of configuration. Compound 3 is converted to optically pure methyl D-alloisoleucinate as its hydrochloride salt, via the methanesulfonate and the azide with 76% yield and 99.9% inversion. Subsequent protection-saponification-activation of 7, followed by reaction with the lithium enolate of methyl trimethylsilyl malonate and reduction, yields (3S,4R,5S)-N-(9-fluorenylmethoxycarbonyl) isostatine. (3S,4R,5S)-Isostatine is a characteristic unit of the didemnines