Dehydro-a-aminobutyric acid

Dehydroalanine (Dha) and dehydro-a-aminobutyric acid, a putative dehydration product of threonine occur accumulated in a particular class of antibiotic fungal peptides recently named lantibiotics of which Nisin (Fig. 26) will be mentioned first. The structure of the 34-peptide as revealed by Erhard Gross and coworkers in the beginning of the seventies, contains three dehydro side chains, RCH=C(NH—)CO—, and five thioether amino acids, lanthionine, Ala-S-Ala and its homolog Abu-S-Ala. Total synthesis by the group of Tetsuo Shiba (Plate 43) [61]. 

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