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An efficient green and sustainable protocol has been devised for the selective oxidative halogenation of acetanilides, benzanilides, sulphonamides, and heterocyclic compounds, using easily available NaX as a halogen source and Oxone as a powerful oxidant. Reaction products were analyzed by GC‐MS. Defined experimental conditions provided the mono and dihalo compounds. The present protocol is simple and environmentally benign to conduct the laboratory scale halogenations and can be extended to prepare industrially important compounds. [ABSTRACT FROM AUTHOR]

The present study deals with conventional Witting olefination of 2 H-chromene-3-carbaldehydes with stabilized ylide in the presence of dichloromethane to afford (2 E)-ethyl-3-(4-chloro-2H-chromen-3-yl) acrylate derivatives. All the products were found to have E-geometry at C=C bond. The synthesized compounds were characterized by spectral data such as IR, H NMR and MS. Compounds were screened for antimicrobial activity against strains of gram positive, gram negative bacterial and fungal strains. All compounds showed good antibacterial and antifungal activity. [ABSTRACT FROM AUTHOR]

Series of 4H-chromone-based hydrazones 3a–z, pyrazolecarboxylates 5a–x and pyrazolylmethanones 6a–u were prepared and screened for their anti-proliferative activity on A549, HeLa, DU145 and MDAMB 231 cell lines. The hydrazone compound 3s with a chloro substituent on the chromanone moiety and a methoxy group on the phenyl ring displayed promising activity on A549, HeLa and DU145 cell lines. The compound 5p with a bromo substituent on the chromanone moiety and a methyl group on the phenyl ring displayed potent activity on DU145. Furopyrazolecarboxylate 5w having a methyl substituent on the phenyl ring displayed potent activity on HeLa cell line. The pyrazolylmethanone 6e with a fluoro substituent on the phenyl ring and compound 6j having a methyl substituent on the chromanone moiety and a methoxy group on the phenyl ring have shown promising anti-proliferative activity on HeLa cell line.

Regioselective cleavage of epoxides with aromatic amines in the presence of tungstophosphoric acid (H3 PW12O40) is described. The reaction proceeded rapidly and afforded the corresponding b-amino alcohols in moderate to high yields. [ABSTRACT FROM AUTHOR]

An efficient and chemoselective deprotection of prenyl ethers of phenols and alcohols with ZrCl4/NaBH4 in DCM was achieved in high yields. The selectivity of prenyl ether deprotection is well demonstrated by carrying out the reaction in the presence of several other ether and ester functionalities. [Copyright &y& Elsevier]

A series of novel pyrazolyl alcohols (5a-h), pyrazolyl azides (6a-h), and pyrazolyltriazoles (8a-h, 10a-p and 12a-l) were prepared and evaluated for their bioactivity (anti-bacterial and anti-inflammatory) profile. The compound 5c displayed the potent anti-bacterial activity against Micrococcus luteus (MIC 3.9 and MBC 7.81µg/mL). In vitro anti-inflammatory activity data denoted that compound 8b is effective among the tested compounds against IL-6 (IC 50 6.23μM). Docking analysis of compounds 5f, 8a-b, 8e-f and 8h displayed high binding energies for the compounds 8a-b and 8h towards TNF-α dimer (2AZ5 protein) and IL-6 (1ALU protein). In vivo anti-inflammatory activity of compounds 8b and 8h with respect to LPS induced mice model indicated that compound 8h showed significant reduction in TNF-α., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Glycosidases play an important role in a wide range of physiological and pathological conditions, and have become potential targets for the discovery and development of agents useful for the treatment of diseases such as diabetes, cancer, influenza, and even AIDS. In this study, several benzimidazole derivatives were prepared from o-phenylenediamine and aromatic and heteroaromatic carboxaldehydes in very good yields, using PdCl2(CH3CN)2 as the most efficient catalyst. Synthesized compounds were assayed for their activity on yeast and rat intestinal alpha-glucosidase inhibition and cytotoxic activity against colon carcinoma cell line HT-29. Compound 3e exhibited 95.6% and 75.3% inhibition of yeast and rat intestinal alpha-glucosidase enzyme, while showing 74.8% cytotoxic activity against the HT-29 cell line at primary screening concentrations of 2.1 mM for yeast and rat intestinal alpha-glucosidase enzyme and 0.2 mM for cytotoxic activity against the HT-29 cell line, respectively. Compound 3c displayed 76% and 34.4% inhibition of yeast and rat intestinal alpha-glucosidase enzyme, and 80.4% cytotoxic activity against the HT-29 cell line at similar primary screening concentrations. The IC50 value for the most potent intestinal alpha-glucosidase inhibitor compound 3e was found to be 99.4 microM. The IC50 values for the most active cytotoxic compounds 3c and 3e were 82 microM and 98.8 microM, respectively. Both compounds displayed significant antihyperglycemic activity in starch-induced postprandial hyperglycemia in rats. This is the first report assigning yeast and rat intestinal alpha-glucosidase enzyme inhibition, cytotoxic activity against the HT-29 cell line, and antihyperglycemic activity to benzimidazole compounds 3c and 3e.

The methanolic extract of rhizome of Himalayan rhubarb Rheum emodi displayed mild yeast as well as mammalian intestinal alpha-glucosidase inhibitory activity. However, further fractionation of active extract led to the isolation of several potent molecules in excellent yields, displaying varying degrees of inhibition on two test models of alpha-glucosidase. Rhapontigenin, desoxyrhapontigenin, chrysophanol-8-O-beta-d-glucopyranoside, torachrysone-8-O-beta-d-glucopyranoside displayed potent yeast alpha-glucosidase inhibition. However chrysophanol-8-O-beta-d-glucopyranoside, desoxyrhaponticin and torachrysone-8-O-beta-d-glucopyranoside displayed potent to moderate mammalian alpha-glucosidase inhibitory activity. Other compounds displayed mild activity on both the tests. Except desoxyrhapontigenin and rhapontigenin that increased Vmax, other compounds including crude extract decreased the Vmax significantly (p<0.02) in yeast alpha-glucosidase test. Further kinetic analysis on mammalian alpha-glucosidase inhibition showed that chrysophanol-8-O-beta-d-glucopyranoside, desoxyrhaponticin and torachrysone-8-O-beta-d-glucopyranoside may be classified as mixed-noncompetitive inhibitors. However, desoxyrhapontigenin and rhapontigenin may be classified as modulators of enzyme activity. Presence and position of glycoside moiety in compounds appear important for better inhibition of mammalian alpha-glucosidase. This is the first report assigning particularly, mammalian intestinal alpha-glucosidase inhibitory activity to these compounds. Chrysophanol-8-O-beta-d-glucopyranoside, desoxyrhaponticin, desoxyrhapontigenin and rhapontigenin have been isolated in substantial yields from R. emodi for the first time. Therefore, these compounds may have value in the treatment and prevention of hyperglycemia associated diabetes mellitus.