Investigation of Diketopiperazines Containing a Guanidino-Functionalized Sidechain as Potential Catalysts of Enantioselective Strecker Reactions
Diketopiperazine 1 consisting of L-(γ-guanidino-α-amino)butyric acid and L-phenylalanine was synthesized as the hydroacetate and as the hydronitrate. Its structure was confirmed by X-ray analysis. In contrast to reports in the literature (Lipton et al.), compound 1 does not induce enantioselevtive catalysis of Strecker reactions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)