Design and microwave-assisted synthesis of dimers of 1,5-benzodiazepine-1,2,3-triazole hybrids bearing alkyl/aryl spacers and their biological assessment

Large series of novel N-bis-1,2,3-triazolo-linked-1,5-benzodiazepin-2-ones (BZD) have been synthesized under microwave irradiation through a Cu(I)-catalyzed double 1,3-dipolar alkyne-azide coupling reaction. This process is of considerable synthetic advantages in terms of time saving and remarkable yields. The chemical structures of the isolated compounds have been elucidated on the basis of extensive spectroscopic methods including 1D & 2D NMR, IR and HRMS. All the synthesized compounds have been evaluated for their antimicrobial and antioxidant activities. In vitro antimicrobial environment, almost all of compounds have shown an interesting activity. Among the dimers of 1,5-benzodiazepine-1,2,3-triazole compounds tested, the results revealed that the potent antibacterial was recorded to compounds 3g,l for Gram-positive (within MIC = 31.25 and 125 μg/mL), and 3h,k for Gram-negative (within MIC = 31.25 and 125 μg/mL). Besides, the results demonstrate that compounds 3h,k have demonstrated the strongest potential against all the tested fungus (within MIC = 62.5 and 125 μg/mL). The antioxidant evaluation indicated that most compounds exhibited a moderate to good biological activity.