Purines, pyrimidines, and imidazoles. Part XXVII. The synthesis of some derivatives and analogues of N-(5-amino-1-β-D-ribofuranosylimidazole-4-carbonyl)-L-aspartic acid 5′-phosphate (SAICAR) including a competitive enzyme (adenylosuccinate AMP-lyase no. 4.3.2.2.) inhibitor-N-(5-amino-1-β-D-ribofuranosylimidazole-4-carbonyl)-L-threo-β-methyl aspartic acid 5′-phosphate

Abstract

Several analogues of N-(5-amino-1-β-D-ribofuranosylimidazole-4-carbonyl)-L-aspartic acid 5′-phosphate (SAICAR) have been prepared by reaction of 5-amino-1-β-D-ribofuranosylimidazole-4-carboxylic acid with a number of α-amino-acids and dicyclohexylcarbodi-imide, and phosphorylation of the products. One of the derivatives of SAICAR namely N-(5-amino-1-β-D-ribofuranosylimidazole-4-carbonyl)-L-threo-β-methylaspartic acid 5′-phosphate was a competitive inhibitor of the enzyme adenylosuccinase. The mechanism of the enzyme-catalysed deamidation of SAICAR is discussed.