Synthesis and effects on arginase and nitric oxide synthase of two novel analogues of Nω-hydroxyarginine, Nω-hydroxyindospicine and p-hydroxyamidinophenylalanine

Abstract
Two novel amino acids, Nω-hydroxy-D,L-indospicine and p-hydroxyamidino-D,L-phenylalanine, have been synthesized in four steps from tert-butoxycarbonylglycine. Both compounds act as good inhibitors of arginase, Nω-hydroxyindospicine being one of the best inhibitors of this enzyme known so far (IC50= 50 µmol dm–3). In contrast, with brain NO synthase the two compounds are almost without effect.