摘要:
The eight possible stereoisomers of isostatine, (3S,4R,5S)-4-amino-3-hydroxy-5-methylheptanoic acid, have been synthesized from the four isomeric D- and L-isoleucinals and D- and L-allo-isoleucinals and ethyl lithioacetate. The eight isomers have been compared for the GC retention times of their bis(trifluoroacetyl) methyl ester derivatives and the H-1 NMR properties of the gamma-lactams derived from them. The natural isomer was shown to be the 3S,4R,5S isomer.