Conventional and microwave-assisted synthesis of imidazole and guanidine derivatives and their biological evaluation

Abstract

A number of imidazole derivatives 3a-f and 4a-f have been synthesized by the condensation of 3-methylthiophen-2-carboxaldehyde 1a, 5-methylthiophen- 2-carboxaldehyde 1b, N-methylpyrrol-2-carboxaldehyde 1c, 1-naphthaldehyde 1d, 2-naphthaldehyde 1e, and 2-hydroxy-1-naphthaldehyde 1f with 1,2- diaminoanthraquinone 2a and 2,3-diaminophenazine 2b, respectively. Condensation of 2-guanidinobenzimidazole with functionalized aldehydes 1a-f leads to the formation of guanidine derivatives 5a-f. Both imidazole (3a-f, 4a-f) and guanidine derivatives (5a-f) were synthesized in good yields using conventional heating and microwave irradiation techniques. Structures assigned to compounds 3a-f, 4a-f and 5a-f are supported by correct spectral and analytic data. On screening for anti-inflammatory and anticancer activities, compounds 3e, 4a and 5a exhibited good anti-inflammatory and compounds 3d, 3f, 4d and 4f showed very good anticancer activity. © Springer Science+Business Media, LLC 2010.