Synthesis and Anticonvulsant Effect of Novel Thiazolidinedione Containing Benzene-sulfonylurea and Sulfonylthiourea Derivatives.

A newer series of 1-(4-substitutedphenyl)-3-(4-((2,4-dioxothiazolidin-5-lidene)methyl)phenyl sulfonyl)urea/thiourea (4a-l) were synthesized for their anticonvulsant activity. The activity is attributed to its potential to restrain astrocytic Na+, 2HCl, and K+ co-transport similar to torasemide which has sulfonylurea in its structure. Torasemide having the similar action as the furosemide that obstructs kainic acid-induced electrical discharges observed from cortex and it has neuroprotective agents, for instance antagonizing the N-methyl-D-aspartate (NMDA) and non-NMDA receptors for evaluating antiepileptic activity. The structures of new derivatives were established by elemental analysis and spectroscopic techniques viz. FTIR, 1H NMR and LC-MS. The all twelve derivatives were assessed for anticonvulsant activity at three different doses at 30, 100 and 300 mg/kg body weight into maximal electroshock (MES) and subcutaneous pentylenetetrazole (sports) models. Compounds 4c and 4e were formed to be most active among all the derivatives for both the models of anticonvulsant activity. Beside these compounds 4g, 4i and 4k also possessed the prominent anticonvulsant activity devoid of any neurotoxicity. The sulfonylurea and sulfonylthiourea both were proved to be effective anticonvulsant pharmacophore. Other structure activity relationships were established by considering the aspect of substitution in the lead.

Anticonvulsant and Neurotoxicity of Some Novel 1-([1,3,4]thiadiazino[6,5- b]indol-3-yl Semicarbazides.

In the present study a series of new N(4)-(4-substituted benzylidene)-N(1)-([1,3,4]thiadiazino [6,5-b]indol-3-yl)semicarbazide (1-6), N(4)-([1,3,4]thiadiazino[6,5-b]indol-3-yl)-N(1)-(1-(4-substituted phenyl)ethylidene)semicarbazide (7-10), N(4)-([1,3,4]thiadiazino[6,5-b]indol-3-yl)-N(1)-((4-substituted phenyl)(phenyl)methylene) semicarbazide. (11-14) have been synthesized from isatin and thiosemicarbazide through multiple steps to meet structural necessities for the anticonvulsant activity. All the newly prepared compounds were characterized by spectral techniques like FT-IR, (1)H and (13)C NMR, EI-MS and elemental analysis. All the newly synthesized compounds were investigated for the anticonvulsant activity against maximal electroshock induced seizures (MES) and subcutaneous pentylenetetrazole (scPTZ) models and their neurotoxicity were also evaluated by rotarod test. The results obtained showed that 64% of the compounds showed protection in the MES test and 36% of the compounds showed protection in ScPTZ test. Some of the compounds also showed good activity after oral administration. Among the synthesized compounds, compound 14 was shown to be the most active compound showing activity at 100 and 300 mg/kg in MES and ScPTZ test with prolonged duration of action. In the present study, semicarbazones of hydroxy containing carbonyl compounds were depicted to be the potent molecule with low neurotoxicity and prolong duration of action on oral administration. The result of the present study may be used for the future development of novel anticonvulsants with broad spectrum of anticonvulsant activity.