Synthesis of New 1-Substituted-1H-1,2,3,4-Tetrazoles from L-α-Amino Acids and Their Biological Assays

A new series of 1-substituted 1H-1,2,3,4-tetrazoles was synthesized from the reaction of L-α-amino acids, triethylorthoformate and sodium azide in glacial acetic acid at 80 °C in good yields (55-80 %). Not only acetic acid is a good solvent but also an effective catalyst promoting the reaction compared with the Lewis acids/microwave, Lewis acids/ ultrasonic or Lewis acids/solvent-free conditions to give the corresponding 1H-1,2,3,4-tetrazoles. Also, the antimicrobial activity investigations (antibacterial activity against E. coli and antifungal activity against Candida albicans) showed that all the tetrazoles obtained were inactive except the one obtained from tryptophan. In addition, the obtained 1- substituted 1H-1,2,3,4-tetrazoles were resistant in different reducing and oxidizing conditions.