Synthesis of benzimidazoles bearing oxadiazole nucleus as anticancer agents

Article abstract of DOI:10.1016/j.ejmech.2012.04.027

Starting from 4-(1H-benzo[d]imidazol-2-yl)-4-oxobutanehydrazide (1), twenty new 1-(1H-benzo[d]imidazol-2-yl)-3-(1,3,4-oxadiazol-5-substituted derivatives-2-yl)propan-1-ones (1b-A_7-26) were synthesized under microwave irradiation in good yields. Further, compound 1b-A₇ was reacted with different secondary amines under microwave irradiation to produce five novel 1-(1H-benzo[d]imidazol-2-yl)-3-(5-(methyl substituted)-1,3,4-oxadiazol-2-yl)propan-1-ones (1b-A_{7a -e}). The title compounds were screened for their in vitro anticancer activity at National Cancer Institute (NCI), USA; at a single dose (10 μM) in NCI 60 cell line panel and results showed significant to good anticancer activity. One compound, 1b-A₁₈ (NSC: 759205), 1-(1H-benzo[d]imidazol-2-yl)-3-(5-(2,4-dichlorophenyl)-1,3,4-oxadiazol-2-yl) propan-1-one, emerged as lead compound; it was selected for five-dose level screening and found to have significant growth inhibition activity.