Mahadev N. Kumbar

Design, synthesis and pharmacological analysis of 5-[4′-(substituted-methyl)[1,1′-biphenyl]-2-yl]-1H-tetrazoles

In the present paper 5-[4′-({4-[(4-aryloxy)methyl]-1H-1,2,3-triazol-1-yl}methyl)[1,1′-biphenyl]-2-yl]-1H-tetrazoles (5a–g) and [2′-(1H-tetrazol-5-yl)[1,1′-biphenyl]-4-yl]methyl-substituted-1-carbodithioates (11h–q) have been designed and synthesized. These compounds were subjected to docking (against AT1 receptor protein enzyme in complex with Lisinopril), in vitro angiotensin converting enzyme inhibition, anti-proliferative, anti-inflammatory screening (through egg albumin denaturation inhibition and red blood cell membrane stabilization assay) and finally anti-fungal activity analyses. Some of the compounds have shown significant pharmacological properties.

Design and Microwave Assisted Synthesis of Coumarin Derivatives as PDE Inhibitors

Coumarins appended to benzimidazole through pyrazole are designed and synthesized using microwave irradiation. These compounds were analyzed for phosphodiesterase (PDE) inhibition indirectly by motility pattern in human spermatozoa. Some of the synthesized compounds, namely, 5d, 5e, 5f, 5g, 5h, and 5k, have exhibited potent inhibitory activity on PDE.

One-pot multicomponent synthesis of novel thiazol-2-imines via microwave irradiation and their antifungal evaluation

Abstract Microwave-assisted green approach is developed for an efficient synthesis of thiazol-2-imines under catalyst-free conditions. The desired products are formed by one-pot three-component reaction which is an improvised method for Hantzsch thiazole synthesis. The microwave-assisted protocol gives excellent yields with high purity in just 10–15 min. All the synthesized compounds have been screened for antifungal activity and some of the derivatives show a broad spectrum against fungal pathogens. Graphical Abstract

Synthesis, Photophysical and Computational Study of Novel Coumarin Based Organic Dyes

A series of novel coumarin pyrazoline moieties combined with tetrazoles, 3‐(1‐phenyl‐4‐(1H‐tetrazol‐5‐yl)‐1H‐pyrazol‐3‐yl)‐2H‐chromen‐2‐one, 6‐chloro‐3‐(1‐phenyl‐4‐(1H‐tetrazol‐5‐yl)‐1H‐pyrazol‐3‐yl)‐2H‐chromen‐2‐one, 6‐bromo‐3‐(1‐phenyl‐4‐(1H‐tetrazol‐5‐yl)‐1H‐pyrazol‐3‐yl)‐2H‐chromen‐2‐one and 6‐bromo‐3‐(1‐(4‐bromophenyl)‐4‐(1H‐tetrazol‐5‐yl)‐1H pyrazol‐3‐yl)‐2H‐chromen‐2‐one7(a‐d), were designed and synthesized. Single crystal X‐ray diffraction and their interactions were studied by Hirshfeld surface analysis. Thermal stabilities and electrochemical properties of these compounds were examined from differential scanning calorimetry (DSC), thermogravimetric (TGA) and cyclic voltammetric (CV) studies. Their spectroscopic properties were analyzed in various alcohols and general solvents by UV–Vis absorption, fluorescence and time‐resolved spectroscopy. In addition, the ground and excited state electronic properties were investigated using density functional theory (DFT). The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and energy band gap (Eg) values have revealed the effect of substitution of halogens. The substitution has equally affected the ground and excited states of 7(a‐d) compounds. The solvatochromism on absorption, fluorescence spectra and fluorescence lifetimes of these compounds was investigated. All these results showed the chromen‐2‐one of pyrazoline tetrazole derivatives could play an important role in photonic and electronic devices.

Synthesis and Anti-Proliferative Activity of Biphenyl Derived 5-Substituted-Indolin-2-Ones

A series of novel biphenyl derived 5-substituted-indolin-2-one derivatives were synthesized by the reaction of 6-chloro-5-(2-chloroethyl)-indolin-2-one 1 with cyclic secondary amines 2a-h followed by condensation of bromomethylcyanobiphenyl to afford the compounds 5a-h. The nitrile group of 5a-h was converted into tetrazole to obtain the compounds 7a-h and tetrazole of 7a-h was further ring transformed into oxadiazole to get compounds 8a-h. Molecular docking study of these previously unknown molecules was performed on PDB: 453D to analyze the interaction and preferred binding mode of synthesized molecules with DNA. Anti-proliferative activity of these newly synthesized compounds were evaluated against a panel of 60 human cancer cell lines at National Cancer Institute (NCI), Bethesda USA. Among these, seven (07) compounds were evaluated for their anti-cancer activity. Some of the compounds displayed potent anti-proliferative activity at 10 µM.

Design, docking studies and molecular iodine catalyzed synthesis of benzo (a)xanthen-one derivatives as hyaluronidase inhibitors

A series of novel benzo[a]xanthen-11(12H)-one derivatives 4a–m were designed and subjected to docking studies. The title compounds were synthesized from 3-aryl-4-formylsydnones 1a–m, β-naphthol and dimedone in presence of molecular iodine as a catalyst and evaluated for their in vitro inhibitory effects on the hyaluronidase.

1-(4-Chloro­phen­yl)-1H-1,2,4-triazol-5(4H)-one

In the title compound, C8H6ClN3O, the dihedral angle between the 1,2,4-triazole and benzene rings is 4.60 (9)° and an intramolecular C—H⋯O interaction closes an S(6) ring. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds generate R 2 2(8) loops and C—H⋯O interactions link the dimers into [100] chains. Weak π–π stacking interactions [centroid–centroid distance = 3.644 (1) Å] are also observed.