Synthesis, Characterization, In Silico DFT, Molecular Docking, and Dynamics Simulation Studies of Phenylhydrazono Phenoxyquinolones for Their Hypoglycemic Efficacy.

A series of novel 24 phenylhydrazono phenoxyquinoline derivatives were synthesized with moderate to excellent yield and screened for their efficacy against the α-amylase enzyme through in silico studies. The structures were characterized using spectroscopic techniques such as 1HNMR, 13CNMR, and HREI-MS. Comprehensive computational studies including, drug-likeness and ADMET profiling, quantum chemical calculations, molecular docking, and molecular dynamics (MD) simulation studies, were performed. A density functional theory study of the synthesized compounds indicated a favorable reactivity profile. The synthesized novel analogues were docked against α-amylase (PDB 6OCN) enzymes to investigate the binding interactions. Based on the docking studies, one of the compounds was found to be the hit with the highest negative binding affinity for α-amylase. A MD simulation study indicated stable binding throughout the simulation.

Palladium-Mediated Synthesis of 2-([Biphenyl]-4-yloxy)quinolin-3-carbaldehydes through Suzuki-Miyaura Cross-Coupling and Their in Silico Breast Cancer Studies on the 3ERT Protein.

A series of novel quinoline appended biaryls have been synthesized (5a-5o) by reacting various substituted boronic acids (4e-4h) with various substituted 2-(4-bromophenoxy)quinolin-3-carbaldehydes (3a-3d) through carbon-carbon bond formation. Effects of various quinoline appended biaryls (5a-5o) on the breast cancer protein 3ERT are moderate to high, as found by in silico molecular docking studies. Comparatively, all quinoline appended biaryls (5a-5o) 5h show better efficacy with a binding energy of -9.39 kcal/mol, and hydrogen bonds are Thr347, Glu353, and Arg394 in the binding pocket. Conclusively, the final novel quinoline appended biaryls (5a-5o) have been confirmed with all the spectral studies, and their efficacy has been validated with in silico studies.

Regioselective synthesis of 2-chloroquinoline based ethyl 4-(3- hydroxyphenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3- carboxylates and their in-silico evaluation against P. falciparum lactate dehydrogenase.

The reaction of various substituted 2, 4-dichloroquinolines with ethyl 4-(3-hydroxyphenyl)- 2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexahydroquinoline-3-carboxylate was carried out in the presence of K2CO3 as a mild and efficient base at controlled temperature leading to novel 2-chloroquinoline based polyhydroquinoline with high regioselectivity. All the synthesized compounds were characterized using IR, NMR, Mass spectral data and then subjected to an in-silico analysis against P. falciparum lactate dehydrogenase.

Flavonoid from Carica papaya inhibits NS2B-NS3 protease and prevents Dengue 2 viral assembly.

UNLABELLED: Dengue virus belongs to the virus family Flaviviridae. Dengue hemorrhagic disease caused by dengue virus is a public health problem worldwide. The viral non structural 2B and 3 (NS2B-NS3) protease complex is crucial for virus replication and hence, it is considered to be a good anti-viral target. Leaf extracts from Carica papaya is generally prescribed for patients with dengue fever, but there are no scientific evidences for its anti-dengue activity; hence we intended to investigate the anti-viral activity of compounds present in the leaves of Carica papaya against dengue 2 virus (DENV-2). We analysed the anti-dengue activities of the extracts from Carica papaya by using bioinformatics tools. Interestingly, we find the flavonoid quercetin with highest binding energy against NS2B-NS3 protease which is evident by the formation of six hydrogen bonds with the amino acid residues at the binding site of the receptor. Our results suggest that the flavonoids from Carica papaya have significant anti-dengue activities. ABBREVIATIONS: ADME - Absorption, distribution, metabolism and excretion, BBB - Blood brain barrier, CYP - Cytochrome P450, DENV - - Dengue virus, DHF - Dengue hemorrhagic fever, DSS - Dengue shock syndrome, GCMS - - Gas chromatography- Mass spectrometry, MOLCAD - Molecular Computer Aided Design, NS - Non structural, PDB - Protein data bank, PMF - Potential Mean Force.

ß-Keto esters from ketones and ethyl chloroformate: a rapid, general, efficient synthesis of pyrazolones and their antimicrobial, in silico and in vitro cytotoxicity studies.

BACKGROUND: Pyrazolones are traditionally synthesized by the reaction of ß-keto esters with hydrazine and its derivatives. There are methods to synthesize ß-keto esters from esters and aldehydes, but these methods have main limitation in varying the substituents. Often, there are a number of methods such as acylation of enolates in which a chelating effect has been employed to lock the enolate anion using lithium and magnesium salts; however, these methods suffer from inconsistent yields in the case of aliphatic acylation. There are methods to synthesize ß-keto esters from ketones like caboxylation of ketone enolates using carbon dioxide and carbon monoxide sources in the presence of palladium or transition metal catalysts. Currently, the most general and simple method to synthesize ß-keto ester is the reaction of dimethyl or ethyl carbonate with ketone in the presence of strong bases which also requires long reaction time, use of excessive amount of reagent and inconsistent yield. These factors lead us to develop a simple method to synthesize ß-keto esters by changing the base and reagent. RESULTS: A series of ß-keto esters were synthesized from ketones and ethyl chloroformate in the presence of base which in turn are converted to pyrazolones and then subjected to cytotoxicity studies towards various cancer cell lines and antimicrobial activity studies towards various bacterial and fungal strains. CONCLUSION: The ß-keto esters from ethyl chloroformate was successfully attempted, and the developed method is simple, fast and applicable to the ketones having the alkyl halogens, protecting groups like Boc and Cbz that were tolerated and proved to be useful in the synthesis of fused bicyclic and tricyclic pyrazolones efficiently using cyclic ketones. Since this method is successful for different ketones, it can be useful for the synthesis of pharmaceutically important pyrazolones also. The synthesized pyrazolones were subjected to antimicrobial, docking and cytotoxicity assay against ACHN (human renal cell carcinoma), Panc-1 (human pancreatic adenocarcinoma) and HCT-116 (human colon cancer) cell line, and lead molecules have been identified. Some of the compounds are found to have promising activity against different bacterial and fungal strains tested.