Arabinda Ray

1, 2, 4-triazole and 1, 3, 4-oxadiazole analogues: synthesis, MO studies, in silico molecular docking studies, antimalarial as DHFR inhibitor and antimicrobial activities

1,2,4-Triazole and 1,3,4-oxadiazole analogues are of interest due to their potential activity against microbial and malarial infections. In search of suitable antimicrobial and antimalarial compounds, we report here the synthesis, characterization and biological activities of 1,2,4-triazole and 1,3,4-oxadiazole analogues (SS 1-SS 10). The molecules were characterized by IR, mass, 1H NMR, 13C NMR and elemental analysis. The in vitro antimicrobial activity was investigated against pathogenic strains, the results were explained with the help of DFT and PM6 molecular orbital calculations. In vitro cytotoxicity and genotoxicity of the molecules were studied against S. pombe cells. In vitro antimalarial activity was studied. The active compounds were further evaluated for enzyme inhibition efficacy against the receptor Pf-DHFR computationally as well as in vitro to prove their candidature as lead dihydrofolate reductase inhibitors.

Phytol induces ROS mediated apoptosis by induction of caspase 9 and 3 through activation of TRAIL, FAS and TNF receptors and inhibits tumor progression factor Glucose 6 phosphate dehydrogenase in lung carcinoma cell line (A549)

A number of drugs as well as lead molecules are isolated from natural sources. Phytol is one of such lead molecule belongs to terpenes group distributed widely in medicinal plants. In the present work, we investigated the cytotoxic behavior of phytol on human lung carcinoma cells (A549). Phytol was found to cause characteristic apoptotic morphological changes and generation of ROS in A549 cells. The mechanism of phytol involved the activation of TRAIL, FAS and TNF-α receptors along with caspase 9 and 3. In silico molecular docking studies revealed that phytol has a good binding affinity with glucose-6-phosphate dehydrogenase (G6PD), which is known to promote tumor proliferation. The ability of phytol to become potential drug candidate has been revealed from the pharmacokinetic study performed in the present study.

Synthesis, characterization and in silico designing of diethyl-3-methyl-5-(6-methyl-2-thioxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxamido) thiophene-2,4-dicarboxylate derivative as anti-proliferative and anti-microbial agents

A series of eight compounds diethyl-3-methyl-5-(6-methyl-2-thioxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxamido) thiophene-2,4-dicarboxilate (KM10-17) analogues have been prepared by conventional methods and characterized by IR, Mass, NMR and elemental analysis. In silico docking studies on Human topoisomerase IIbeta (PDB Id: 3QX3) have been performed for all molecules (KM10-17) synthesized. The compounds were tested for in vitro anti-proliferative activity on VERO and 786-O cell lines. Out of all the synthesized compounds, KM11 &KM16 showed moderate activity on both cell lines. In vitro anti-microbial activity was also checked against Bacillus subtilis (BS), Staphylococcus aurous (SA), Pseudomonas aeruginosa (PA), Escherichia coli (EC) and Candida albicans (CA) by well diffusion method. The compound KM11 was found to have highest zone of inhibition against BS, SA, PA and EC. The molecules KM13 and KM16 exhibited good activity against CA. The compounds KM14 and KM16 indicated good zone of inhibition against BS.

Benzothiazole analogues: synthesis, characterization, MO calculations with PM6 and DFT, in silico studies and in vitro antimalarial as DHFR inhibitors and antimicrobial activities

Benzothiazole analogues are of interest due to their potential activity against malarial and microbial infections. In search of suitable antimicrobial and antimalarial agents, we report here the synthesis, characterization and biological activities of benzothiazole analogues (J 1-J 10). The molecules were characterized by IR, Mass, 1H NMR, 13C NMR and elemental analysis. The in vitro antimicrobial activity was investigated against pathogenic strains; the results were explained with the help of DFT and PM6 molecular orbital calculations. In vitro cytotoxicity and genotoxicity of the molecules were studied against S. pombe cells. In vitro antimalarial activity was studied. The active compounds J 1, J 2, J 3, J 5 and J 6 were further evaluated for enzyme inhibition efficacy against the receptor Pf-DHFR, computational and in vitro studies were carried out to examine their candidatures as lead dihydrofolate reductase inhibitors.

6-Tosyl-4,5,6,7-Tetrahydrothieno[2,3-c]Pyridine-3-Carboxamide Analogues: Synthesis, Characterization, MO Calculation, and Antibacterial Activity

A series of 6-tosyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxamide analogues are synthesized by conventional techniques and characterized by elemental analysis, IR, MS, 1H, and 13C NMR. These are tested for their antibacterial activity against Bacillus subtilis (abbreviated as BS), Staphylococcus aureus (abbreviated as SA), and Escherichia coli (abbreviated as EC). The synthesized compounds are able to inhibit the growth of the SA and EC. None of the compounds are effective against BS. All valence molecular orbital (abbreviated as MO) calculations with PM6 have been carried out for the molecules for which bioactivity data are available. Ciprofloxacin is taken as the standard antibiotics to compare activity with the molecules synthesized. It has been attempted to correlate the activity of the molecules with their electronic structure.

Synthesis, characterization, in silico molecular docking study and biological evaluation of a 5-(phenylthio) pyrazole based polyhydroquinoline core moiety

A multicomponent cyclocondensation reaction has been developed by incorporating 3-methyl-5-substituted phenylthio-1-phenyl-1H-pyrazole-4-carbaldehydes 3a–c, various enaminones 6a–c and different active methylene compounds 7a–c (malononitrile 7a/ethylcaynoacetate 7b/caynoacetamide 7c) in the presence of piperidine as a basic catalyst, to afford a combinatorial library of polyhydroquinoline scaffolds, i.e.8a–p. The targeted compounds were synthesized in good to excellent yields (71–84%). All the synthesized compounds have been characterized by 1H NMR, 13C NMR, IR, mass spectrometric techniques and elemental analysis. All the synthesized compounds were evaluated in vitro for their antibacterial, antitubercular and antimalarial activities. An in silico molecular docking study as well as in silico pharmacokinetics evaluation have been carried out. Many candidates of this new class revealed noticeable activities against first line drugs.

Bioproduction and characterization of extracellular melanin-like pigment from industrially polluted metagenomic library equipped Escherichia coli

To explore the potential genes from the industrially polluted Amlakhadi canal, located in Ankleshwar, Gujarat, India, its community genome was extracted and cloned into E. coli EPI300™-T1R using a fosmid vector (pCC2 FOS™) generating a library of 3,92,000 clones with average size of 40kb of DNA-insert. From this library, the clone DM1 producing brown colored melanin-like pigment was isolated and characterized. For over expression of the pigment, further sub-cloning of the clone DM1 was done. Sub-clone containing 10kb of the insert was sequenced for gene identification. The amino acids sequence of a protein 4-Hydroxyphenylpyruvate dioxygenase (HPPD), which is know to be involved in melanin biosynthesis was obtained from the gene sequence. The sequence-homology based 3D structure model of HPPD was constructed and analyzed. The physico-chemical nature of pigment was further analysed using 1H and 13C NMR, LC-MS, FTIR and UV-visible spectroscopy. The pigment was readily soluble in DMSO with an absorption maximum around 290nm. Based on the genetic and chemical characterization, the compound was confirmed as melanin-like pigment. The present results indicate that the metagenomic library from industrially polluted environment generated a microbial tool for the production of melanin-like pigment.