Reactivity Studies on a Novel 4-(2-hydroxyphenyl)-1,3-dihydro-1,5-benzodiazepine-2-thione

Regioselective One-Pot Synthesis, Biological Activity and Molecular Docking Studies of Novel Conjugates N-(p-Aryltriazolyl)-1,5-benzodiazepin-2-ones as Potent Antibacterial and Antifungal Agents

Novel 1,2,3-triazolo-linked-1,5-benzodiazepinones were designed and synthesized via a Cu(I)-catalyzed 1,3-dipolar alkyne-azide coupling reaction (CuAAC). The chemical structures of these compounds were confirmed by 1H NMR, 13C NMR, HMBC, HRMS, and elemental analysis. The compounds were screened for their in vitro antibacterial and antifungal activities. Several compounds exhibited good to moderate activities compared to those of established standard drugs. Furthermore, the binding interactions of these active analogs were confirmed through molecular docking.

Design and Synthesis of (3,5-Disubstituted Isoxazole)-Linked [1,5]-Benzodiazepine Conjugates: Evaluation of their Antimicrobial and Anti-Tyrosinase Activities

A series of novel 2-(3,5-disubstituted isoxazolyl)-1,5-benzodiazepines and 2,4-bis-(3,5-disubstituted isoxazolyl)-1,5-benzodiazepine derivatives have been designed and synthesised by employing an alkyne/nitrile oxide cycloaddition ‘click’ type chemistry protocol. The structures of the compounds were determined on the basis of 1H, 13C and 2D-NMR techniques and by HRMS analysis. These hybrid molecules exhibit moderate to significant antimicrobial and anti-tyrosinase activities.

Chemoselectivity of the 1,3-Dipolar Cycloaddition of Some Diazoalkanes with 1,5-Benzodiazepine Derivatives

Benzodiazepines are pharmaceutically important synthetic materials. Reaction of the 4-(2-hydroxyphenyl)-1,5-benzodiazepin-2-one with 2-diazopropane (DAP) gave a mixture of the 2-isopropylether of 4-(2-hydroxyphenyl)-3H-1,5-benzodiazepine and 1-isopropyl-4-(2-hydroxyphenyl)-3H-1,5-benzodiazepin-2-one. Whilst diphenyldiazomethane (DPDM) gave 1-benzhydryl-4-(2-hydroxyphenyl)-3H-1,5-benzodiazepin-2-one. Reaction of the corresponding thione with DAP led to the 2-isopropylthioether of 4-(2-hydroxyphenyl)-3H-1,5-benzodiazepine and 1-isopropyl-4-(2-hydroxyphenyl)-1,5-benzodiazepine-2-thione while the reaction with DPDM gave the 2-benzhydrylthioether of 4-(2-hydroxyphenyl)-3H-1,5-benzodiazepine. The characterisation of these prepared - N, - O and - S alkylated benzodiazepines involved 1D and 2D-NMR techniques, mass spectrometry and elemental analysis.

Comprehensive DFT and MP2 level investigations of reaction of 2,3-dihydro-1,5-benzodiazepine-2-thiones with hydrazine

Density functional theory approach was used for the 4-phenyl-2,3-dihydro-1,5-benzodiazepine-2-thione compound to determine the mechanism of hydrazinolysis of 4-substituted 2,3-dihydro-1,5-benzodiazepine-2-thiones. Single-point calculations at the MP2/6-311+G(d,p)//B3LYP/6-311+G(d,p) level were performed for the more accurate energy prediction. The solvent effect was taken into account by carrying out single-point calculations using the PCM methodology. The obtained results show that in the investigating mechanism the first step consists of the hydrazine molecule addition to the thiocarbonyl bond of the 4-phenyl-2,3-dihydro-1,5-benzodiazepine-2-thione following removal of H(2)S. Further addition of another hydrazine molecule to the azomethyne bond and cyclization with pyrazole ring formation occur, and then the diazepine ring-opening and the removal of hydrazine molecule proceed. Finally, imine-enamine tautomerization leads to 5-N-(2-aminophenyl-1-amino)-3-phenylpyrazole as a main product that is in agreement with the experimental observation. The cyclization step is a rate-determining step of this reaction.