DESIGN, FACILE SYNTHESIS, AND BIOLOGICAL EVALUATION OF NOVEL 1,3-THIAZINE DERIVATIVES AS POTENTIAL ANTICONVULSANT AGENTS

Objective: Chalcones and their heterocyclic analogs represent an important class of small molecules having anticonvulsant activities. Therefore, inthis study, the synthesis and anticonvulsant activity of some new chalcones and 1,3-thiazines were described.Methods: The reaction of 1-acetylnaphthalene with substituted aromatic aldehydes in the presence of aq. NaOH afforded corresponding chalconeswhich upon further cyclization with thiourea resulted in 1,3-thiazine derivatives. The newly synthesized compounds were tested for anticonvulsantactivity by pentylenetetrazole-induced seizures method using diazepam as standard.Results: Most of the compounds showed good anticonvulsant activity but is less than diazepam. 1,3-thiazines were more potent than chalconesand among them, compound P4 containing 4-fluorophenyl substituents on the thiazine moiety was more potent as it has prolonged the onset ofconvulsions by 155.2 seconds.Conclusion: We described the synthesis and anticonvulsant activity of novel chalcones and 1,3-thiazine derivatives. 1,3-thiazines are more activeanticonvulsant agents than chalcones and in particular compounds with electron withdrawing substituents.Keywords: Chalcone, 1,3-thiazine, Pentylenetetrazole

DEVELOPMENT AND CHARACTERIZATION OF GASTRO RETENTIVE MUCOADHESIVE MICROBEADS CONTAINING SIMVASTATIN WITH DIFFERENT CROSS LINKING AGENTS

Objective: The aim of the present work was to prepare and examine drug release of the oral controlled release microbeads using different curing agents by emulsification internal ionic gelation technique. Methods: Cross-linked alginate microbeads were prepared with different cross linking agents by using mucoadhesive properties. The formation and compatibility of microbeads were confirmed by compatibility studies. Prepared microbeads evaluated for encapsulated efficiency, micromeritic properties, drug loading, in vitro wash off studies, in vitro dissolution studies, drug release kinetics and stability studies Results: The in vitro drug release was influenced by both type of curing agents and type of polymers and no significant changes in characterization parameters was observed after 3 mo stability studies. The sustained release profile of optimized batch was found to be 99.66±0.18% in comparison to pure drug profile of 28.64±0.02% at 12 h release study. Results of both wash-off and in vitro studies suggests that batch (SF2) prepared with aluminium chloride has shown better mucoadhesive property. Drug release of optimized batch follows zero order with non fickian mechanism according to Korsmeyer-Peppas equation. Conclusion: The data suggest the use of simvastatin mucoadhesive cross linked microbeads to offer the potential for oral controlled drug delivery with improved gastric retention and capable to provide sustained drug release by using cross linking agents

A formal stereoselective synthesis of (−)-maurenone

An efficient formal synthesis of marine polypropionate (−)-maurenone is described. Highlights of the strategy include the utilization of a desymmetrization technique and the activation of the epoxide oxygen with a silyl triflate followed by intramolecular -hydride transfer - a novel transformation

Stereoseletive total synthesis of 11-α-and 11-β-methoxycurvularins

Total synthesis of 11-α-methoxycurvularin and 11-β-methoxycurvularin has been accomplished in a highly stereoselective manner by utilizing Jacobsen hydrolytic kinetic resolution, Maruoka asymmetric allylation and intramolecular Friedel-Crafts acylation as key steps

Total synthesis of (+)-aspicilin from D-mannitol

The total synthesis of the 18-membered lichen macrolide, (+)-aspicilin, has been accomplished utilizing the Swern oxidation, Masamune-Roush olefination, and ring-closing metathesis of a trienic ester as key steps. D-Mannitol has been utilized as the chiral pool material for the construction of the olefinic aldehyde and the Jacobsen hydrolytic kinetic resolution has been employed for the construction of the olefinic phosphonate ester

Total synthesis of (+)-bourgeanic acid utilizing desymmetrization strategy

A highly stereoselective total synthesis of an aliphatic depside (+)-bourgeanic acid via (-)-hemibourgeanic acid and bourgeanic lactone is described. The key steps involved in this synthesis are desymmetrization of bicyclic olefin with Brown's asymmetric hydroboration, Gillman's reaction, TEMPO-BAIB mediated selective oxidation of 1,3-diol, Yamaguchi macro-lactonization and LiOH-mediated partial hydrolysis of unusually stable eight-membered cyclic dilactone

Total synthesis of (+)-aculeatin D and (+)-6-epi-aculeatin D

The stereoselective total synthesis of spiroketal natural product (+)-aculeatin D and unnatural (+)-6-epi-aculeatin D has been accomplished. Sharpless kinetic resolution of secondary allylic alcohol and phenyliodine(III) bis(trifluoroacetate) (PIFA)-mediated oxidative spirocyclization were used as key steps in this synthesis