Reaction of amino acids with guanidinating agents

Abstract

The reaction of amino acids with three guanidinating agents, viz. 2-methylpseudourea, 2-methyl-2-thiopseudourea, and guanyl-3,5-dimethylpyrazole, was investigated. The α-amino group of amino acids with an aliphatic side chain was readily convertible to the guanido group. However, the α-amino group of other amino acids was found to be either refractory or slow toward such modification.