POLYMERIZATION OF BETA-AMINO ACIDS IN AQUEOUS-SOLUTION

We have compared carbonyl diimidazole (CDI) and 1-ethyl-3-(3-dimethyla minopropyl) carbodiimide (EDAC) as activating agents for the oligomeri zation of negatively-charged alpha- and beta-amino acids in homogeneou s aqueous solution. alpha-Amino acids can be oligomerized efficiently using CDI, but not by EDAC. beta-Amino acids can be oligomerized effic iently using EDAC, but not by CDI. Aspartic acid, an alpha- and beta-d icarboxylic acid is oligomerized efficiently by both reagents. These r esults are explained in terms of the mechanisms of the reactions, and their relevance to prebiotic chemistry is discussed.