Patent ID: 6967202
Filing Date: 2005-11-22
Classification: C07D

Abstract:
1. A method of synthesizing a diketopiperazines of the following formula: wherein: R R R each R (a) reacting a first amino acid selected from the group consisting of glycine, alanine, valine, leucine, isoleucine, serine, threonine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, hydroxylysine, histidine, arginine, phenylalanine, tyrosine, tryptophan, thyroxine, cysteine, methionine, norvaline and ornithine, with a second amino acid derivative having one of the following formulas: NH NH (b) cyclizing the dipeptide at a temperature of between 80° C. and 180° C. in a neutral solvent to form a diketopiperazine having the formula; wherein: R (c) hydrogenating the diketopiperazine to remove the R wherein: R R