We have prepared the nucleoamino acids 1-(3′-amino, 3′-carboxypropyl)uracil (3) and 9-(3′-amino, 3′-carboxypropyl)adenine (4) as (l)-enantiomers and as racemic mixtures. When 3 or 4 is suspended in water and treated with N,N′-carbonyldiimidazole, peptides are formed in good yield. The products formed from the (l)-enantiomers are hydrolyzed to the monomeric amino acids by pronase. Attempts to improve the efficiency of these oligomerizations by including a polyuridylate template in the reaction mixture were not successful. Similarly, oligomers derived from the (l)-enantiomer of 3 did not act as templates to facilitate the oligomerization of 4. © 1990 Springer-Verlag New York Inc.