Author's Organization：Pharmaceutical Institute, Medical Faculty, University of Kyoto Pharmaceutical Institute, Medical Faculty, University of Kyoto Pharmaceutical Institute, Medical Faculty, University of Kyoto
L-2-Amino-4-guanidinobutyric acid was prepared in a fairly good yield from L-2, 4-diaminobutyric acid by treatment with S-methylisothiourea sulfate after converting the acid to its copper salt and protecting the amino groups in 2-and 4-positions respectively with benzoyl and benzyloxycarbonyl group.
