Synthesis of alpha-, beta- and cyclic spaglumic acids.
A short, one-pot synthesis of alpha- and beta-spaglumic acids (N-acetyl-L-aspartyl-L-glutamic acids, NAAGA) has been developed based on ultrasound-promoted acetylation of aspartic acid, followed by dehydration, condensation with glutamic acid dibenzyl ester and hydrogenolysis. The alpha- and beta-peptides were separated by anion-exchange chromatography. The alpha-peptide shows a remarkable tendency to cyclize during methylation with diazomethane and yields cyclic N-acetylaspartylglutamic acid dimethyl ester, which could be hydrolysed to the hitherto unreported diketopiperazine dicarboxylic acid, cyclic spaglumic acid (cyclic NAAGA).
Vittal Mallya Scientific Research Foundation, Bangalore, India.
A V
AV
Reddy
B
B
Ravindranath
D001993:Bronchodilator Agents / Q000138:chemical synthesis*; D004151:Dipeptides / Q000138:chemical synthesis*; D006634:Histamine H1 Antagonists / Q000138:chemical synthesis*; D007536:Isomerism
D001993:Bronchodilator Agents; D004151:Dipeptides; D006634:Histamine H1 Antagonists; C027172:isospaglumic acid