Spaltung von synthetisch dargestelltem Isoleucin in seine vier optisch-aktiven Komponenten, nämlich l-(+) und d-(—)Isoleucin, sowie d-(—) und l-(+)Alloisoleucin.

Abstract

Isoleueine, prepared by bro- mination of secondary butyl malonic acid and subsequent aminization of the [alpha]-brom-[beta]-methyl-[beta]-ethyl pro-pionic acid, was separated into isoleueine and alloiso-leucine through differential solubilities; the alloisoleucine was purified by ester distillation. Resolution of their formyl derivatives into 1- and d-forms was accomplished by fractional crystallization of the brucine salts, the 1-forms separating out first. The four amino acids, their formyl-, phenylsulfonate, phenyl isocyanate and [alpha]-naph-thyl isocyanate derivatives were characterized.