A series of 3-substituted-1H-isochromene-1-thiones (3) were prepared by the reaction of 3-substituted isocoumarins (2) with Lawesson's reagent in the presence of toluene under a nitrogen atmosphere. The antimicrobial activities of the newly synthesized products were measured using Gram-negative (Escherichia coli, Salmonella typhi, and Proteus mirabilis) and Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus). Synthesized thioanalogue of isocoumarins showed good antibacterial activity against Proteus mirabilis. © Taylor &amp; Francis Group, LLC.

Mohana Roopan S

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Nawaz Khan F

Manivel P

Kumar D.P

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Isocoumarin Thioanalogues as Potential Antibacterial Agents

Phosphorus, Sulfur, and Silicon and the Related Elements

Thyroxine, the main secretory hormone of thyroid gland, is produced from thyroglobulin by thyroid peroxidase/hydrogen peroxide/iodide system. The prohormone T4 is then converted to its potent form T3 by a selenocysteine- containing enzyme iodothyronine deiodinase. Autoantibodies which activate thyroid-stimulating hormone receptor are not under the pituitary feedback control system, and therefore, the uncontrolled production of thyroid hormones leads to a condition called "hyperthyroidism." The overproduction of T4 and T3 can be controlled by specific inhibitors, which either block the synthesis of thyroid hormone or reduce the conversion of T4-T3. Unique classes of such inhibitors are thiourea drugs, methimazole (MMI), 6-n-propyl-2- thiouracil, and carbimazole suggesting that thione moiety exhibit excellent antithyroid activity. We have carried out biomimetic studies by HPLC assay, which suggested that isochromene-1-thiones exhibit significant antithyroid activity by inhibiting the lactoperoxidase (LPO)-catalyzed iodination, comparable with MMI, and that the inhibitory effects of some of them were found to be much superior to those of MMI. Kinetic studies demonstrate that isochromene-1-thiones inhibit LPO irreversibly. Our inhibition studies suggest that isochromene-1-thiones might be another promising candidate with potential for developing therapeutics for hyperthyroidism. The quantitative structure-activity relationship (QSAR) was developed between the LPO-inhibitory activities of isochromene-1-thiones and their physiochemical properties. The statistical measures, such as r2 (0.81), r2adj (0.79), q2 (0.73), and F-ratio (39.05), were found to be within the acceptable range. © 2013 Springer Science+Business Media New York.

Medicinal Chemistry Research

Antithyroid agents and QSAR studies: Inhibition of lactoperoxidase- catalyzed iodination reaction by isochromene-1-thiones

AbstractA new series of 1,2,3-selenadiazoles containing an aryl or a 3-arylisoquinoline sulfanyl moiety at carbons 4 and 5, respectively, was prepared by cyclization of the respective semicarbazones in the presence of selenium(II) oxide and tetrahydrofuran at 70–75°C. Semicarbazones required for the reaction were obtained from 2-((3-arylisoquinolin-1-yl)sulfanyl)-1-phenylethanones, I, by a reaction with semicarbazide hydrochloride in ethanol/water mixture and potassium acetate base.

Chemical Papers

Facile synthesis of 3-aryl-1-((4-aryl-1,2,3-selenadiazol-5-yl)sulfanyl)isoquinolines

AbstractAn efficient ligand-free cross-coupling reaction of 2-chloro-3-(chloromethyl)benzo[h]quinoline with N-heterocycles such as piperidin-4-one, 4(3H)-pyrimidone, and ethyl 6-chloro-1,2-dihydro-2-oxo-4-phenylquinoline-3-carboxylate using a catalytic amount of ZnO nanorods as a recyclable catalyst and KOH as the base in DMSO under reflux at 110°C is reported.

ZnO nanorods catalyzed N-alkylation of piperidin-4-one, 4(3H)-pyrimidone, and ethyl 6-chloro-1,2-dihydro-2-oxo-4-phenylquinoline-3-carboxylate

A series of hydrazinothiazoles has been synthesized by the condensation of thiosemicarbazones and α-bromoketones. Similarly the hydrazinothiazolidiones were prepared by the condensation of thiosemicarbazone and α-bromoesters. The newly synthesized compounds were characterized by NMR and LCMS studies.

Synthesis of Some New 2,4-Disubstituted Hydrazinothiazoles and 2,5-Disubstituted Thiazolidinones

New hydrazine derivatives were synthesized via reaction between 1, 3 cyclic diketones and hydrazinoisoquinoline derivatives. The reaction proceeded smoothly in ethanol under reflux temperature and furnished products in excellent yields (76-87%). The products have been purified and fully characterized by spectroscopy techniques. The compounds 8a-c showed good bacterial inhibition against Bacillus cerus and 8d-f showed good antifungal activity against Candida albicans.

Fulltext

Journal of the Chilean Chemical Society

SYNTHESIS OF 3 SUBSTITUTED ISOQUINOLIN-1-YL-2-(CYCLOALK-2-ENYLIDENE) HYDRAZINES AND THEIR ANTIMICROBIAL PROPERTIES

Synthetic Communications

Synthesis of Some 3‐Substituted Isochromen‐1‐ones

Acta Crystallographica Section E Structure Reports Online

3-Butyl-1H-isochromen-1-one

In the title compound, C13H14OS, a derivative of thio-isocoumarin, the packing is stabilized by weak C - H⋯S, C - H⋯π and π-π [separation 3.7481 (12) Å] inter-actions. © International Union of Crystallography 2007.

Journal	Phosphorus, Sulfur, and Silicon and the Related Elements
Publisher	Informa UK Limited
ISSN	1042-6507
Open Access	0