Synthesis of Novel 6-Amino-Substituted-1,2,4-Triazines scaffolds as Potential Antibacterial Agents

Abstract

1,2,4-Triazine and its derivatives have proven their importance in the biological world since they are used in the treatment of diseases like cancer and HIV/AIDS. Thus this project was aimed at synthesizing novel 1,2,4-triazine-containing compounds, 6-aryl-1,2,4-triazine-3-amines and 6-amino-1,2,4-triazine-3,5-(2H,4H)-diones compounds in particular. Synthesis of 6-amino-1,2,4-triazine-3,5-(2H,4H)-diones started by the bromination of 6-azauracil which was subsequently reacted with different amines like acyclic primary amines, aryl primary amines and secondary amines. Products were obtained in good to excellent yields. Two different classes of 6-aryl-1,2,4-triazine-containing compounds were synthesized. The first class contained the 6-aryl-1,2,4-triazine-3-amine moiety whereas the second class contained the 6-aryl-1,2,4-triazine-3,5-diamine moiety. Synthesis of the first class of compounds commenced by the bromination of 1,2,4-triazine-3-amine which was subsequently reacted with different aryl boronic acids under Suzuki coupling reaction conditions using tetrakis(triphenylphosphine)palladium(0) as a catalyst. Products were obtained in poor to excellent yields. The second class of these novel compounds were obtained by firstly aminating 1,2,4-triazine-3-amine using the Chichibabin reaction followed by the bromination step. The resultant 6-bromo-1,2,4-triazine-3,5-diamine was Suzuki coupled with different aryl boronic acids to obtain desired products in moderate to excellent yields.