[Synthesis of benzimidazole derivatives by amino acid action on ortho-phenylenediamine, variously substituted in positions 4 and 5].

As part of the synthesis of the benzimidazole derivative heterocyclique system, we are interested in studying the condensation of the o-phenylenediamines with amino-acids such as aspartic acid, serine and histidine. The interest that these present is based mainly on their pharmacological properties. They have, in fact anti-inflammatory, antidepressive, antibacterial and antihistamine properties. On the other hand, it should be noted that 5,6-dimethyl-1-(alpha-D-ribofuranosyl) benzimidazole constitutes part of vitamin B12. Taken together, these results led us to pursue our research in this domain while focusing on new methods of benzimidazolic derivative synthesis. It should be said that the obtaining of these compounds depends on the quantity of the amino-acid. All synthesized products have been characterized by infrared, nuclear magnetic resonance and mass spectrometry.