Stereoselective Synthesis of 2,4-Diamino Acids by Asymmetric Hydrogenation

Article abstract of DOI:10.1246/bcsj.62.2315

A stereoselective synthesis of unusual basic amino acids, ornithine, 2,4-diaminopentanoic acid, and 2,4-diamino-6-methylheptanoic acid, was achieved by the hydrogenation of cyclic α,β-dehydro dipeptides obtained by the condensation of cyclo(-Gly-L(or D)-aminoacyl-) and protected linear or chiral amino aldehydes.The degree of chiral induction greatly depended on the bulkiness of the side chains of α,β-dehydro amino acids.The R_f values on paper chromatography of (2S,4S or 2R,4S)-diaminopentanoic acid prepared by the present method were different from the reported values of a compound which had been obtained from metabolic products of Clostridium sticklandii and estimated to be 2,4-diaminopentanoic acid.