scPTZ Model Research Articles

Synthesis and Anticonvulsant Activity of Certain Substituted Furochromone, Benzofuran and Flavone Derivatives

Synthesis of furochromone, 2-phenylchromone (flavone) and benzofuran derivatives substituted with thiosemicarbazide or thiazolidin-4-one moieties were accomplished. All the newly synthesized compounds were tested for their anticonvulsant activity in both subcutaneous pentylenetetrazole induced seizures (scPTZ) and maximal electric shock induced seizures (MES) tests using valproic acid and phenytoin respectively as reference standards. The most active compounds in scPTZ model were 1c, 2b, 5a and 7e showing 100% protection at 300 mg/kg upon intraperitoneal administration. Also, the effect of pre-treatment of three of the most active compounds (1c, 2b, 5a) on 4-amino pyridine-induced lethality in mice was investigated. Pre-treatment with these compounds significantly increased the latency for clonic and tonic seizures and prevented 4-amino pyridine induced death. Hence, this provides evidence for anticonvulsant activity of these compounds, and a neuroprotective activity for them. The structure-activity relationship was studied based on the obtained data.

Design and synthesis of anticonvulsants from a combined phthalimide–GABA–anilide and hydrazone pharmacophore

Two series of pharmacophoric hybrids of phthalimide–GABA–anilides/hydrazones were designed and synthesized and evaluated for their anticonvulsant and neurotoxic properties. The structures of the synthesized compounds were confirmed by the use of their spectral data besides elemental analysis. Initial anticonvulsant screening was performed using intraperitoneal (i.p.) maximal electroshock-induced seizure (MES), subcutaneous pentylenetetrazole (scPTZ), subcutaneous strychnine (scSTY), and intraperitoneal picrotoxin (ipPIC)-induced seizure threshold tests. All of the compounds were ineffective in the MES test. Most of the compounds were found to be effective in the scSTY and ipPIC models and very few compounds showed protection in the scPTZ model.

Synthesis and anticonvulsant activity of 3-(6-substituted-benzothiazol-2-yl)-6-phenyl-[1, 3]-xazinane-2-thiones.

A new series of 3-(6-substituted-benzothiazol-2-yl)-6-phenyl-[1, 3]-oxazinane-2-thiones (4a-j) has been synthesised using an appropriate synthetic route (Scheme 1) and characterised by elemental analyses and spectral (IR, (1)HNMR, (13)C NMR, and EI MS) data. The anticonvulsant activity of all the title compounds (4a-j) was evaluated against Maximal Electroshock (MES) induced seizures and furthermore the most potent compounds were evaluated against subcutaneous pentylenetetrazole (sc PTZ) induced seizures model in mice. The neurotoxicity was assessed using the rotorod procedure. All the test compounds were administered intraperitoneally at various dose levels ranging from 30-200 mg/kg body wt and the median effective dose (ED(50)), median toxic dose (TD(50)), and protection index (PI) values were determined (Table 2). Among the compounds tested, the 3-(6-dimethylaminobenzothiazol-2-yl)-6-phenyl-[1, 3]-oxazinane-2-thiones (4j) was found to be the most potent (ED(50): 9.85 and 14.8 in MES model and 12 and 17 in scPTZ model at t = 0.5 h and 4 h, respectively, and TD(50) 42.8 and 44 at t = 0.5 h and 4 h, respectively, which has been found to be significant at p < 0.01 with respect to reference standard phenytoin) with protection index (PI) 4.85.