Conjugation and cyclization—two strong driving forces leading to the formation of new chromophores

Novel chromophores formed in the solvent reactions of α-amino acids and small peptides were identified by crystal structure analysis and characterized by UV absorption. The formation of these chromophores in basic solutions was attributed to two strong driving forces—conjugation and cyclization. The discussion of possible reaction pathways could benefit the future design of α-amino acid-based chromophores.