Synthesis of novel 3-pyridinecarbonitriles with amino acid function and their fluorescence properties.
A variety of N-[(4,6-diaryl-3-pyridinecarbonitrile)-2-yl] amino acid esters 2-4 were synthesized through the reaction of 2-bromo-3-pyridinecarbonitriles 1 with the appropriate alpha-amino acid ester hydrochloride in refluxing dioxane in the presence of triethylamine as dehydrohalogenating agent. Similarly, N'-glycylglycine analogues 5 were obtained through the reaction of 1 with the dipeptide ester. On the other hand, attempts were made towards the construction of amino acid derivatives 7 through the reaction of 1 with aqueous solution alpha-amino acids 6 in refluxing pyridine, but were unsuccessful, and instead the unexpected 2-amino-3-pyridinecarbonitriles 8 were isolated. The fluorescence properties of the newly synthesized pyridines 2-5 were evaluated. Some of the prepared compounds show considerable antibacterial activity.