Synthesis of new benzimidazole derivatives as potential antimicrobial agents.

Barbiturates 3 as possible antimicrobial agents were obtained by reacting the N,N'-disubstituted urea 1a or the thiourea analogues 1b,c with the magic malonates 2a,b. On the other hand, reaction of 1a with ethoxycarbonyl isocyanate (4) yielded the substituted s-triazine-2,4,6(1H,3H,5H)-trione 5. The reaction of 4 with 2-aminomethyl-benzimidazole (6) gave the allophanate 7 which upon treatment with Na2CO3 yielded N-(1H-benzimidazol-2-yl)urea 8.