SYNTHESIS AND BIOLOGICAL EVALUTION OF 3-CHLORO 2- METHYL PHENYL CARBAMOYL SUBSTITUTED SEMICARBAZONE DERIVATIVES AS POTENTIAL ANTICONVULSANT AGENTS

ABSTRACT A series of 3-chloro 2-methyl phenyl carbamoyl substituted semicarbazones (4-21) was synthesized and evaluated for anticonvulsant and CNS activities. The anticonvulsant activity of the synthesized compounds was established after intraperitoneal administration in three seizure models in mice which include maximal electroshock seizure, subcutaneous pentylenetetrazole, and subcutaneous strychnine-induced seizure screens. All the test compounds were administered at doses of 30, 100, and 300 mg/kg body weight and the anticonvulsant activity was noted at 0.5 and 4 h time intervals after the drug administration . . Aryl semicarbazides have also been reported to display excellent anticonvulsant activity in mice and rats . In terms of interaction at the binding site, as proposed previously by Dimmock et al. the pharma-cophoric elements were thought to be a lipophilic aryl ring and hydrogen bonding semicarbazone moiety. The attach-ment of a second aryl ring designated as the distal ring to the proximal aryl ring to increase the van der Waal's bonding at the binding site and to increase potency have also been reported. Substitutions in the aryl ring by halogens have been found to increase potency in the MES screen

3D QSAR analysis on quinoxaline derivatives as anti-malarial using K-nearest neighbour molecular field analysis

In the present article, k nearest neighbour molecular field analysis (kNN-MFA) method was used to develop a three dimensional quantitative structure activity relationship (3D-QSAR) model. In this study 37 derivatives of quinoxaline having antimalarial activity were used. Sphere exclusion (SE) algorithm was used to create the biological activity data set in to into training and test set. For model generation kNN-MFA method has coupled with stepwise, simulated annealing and genetic algorithm this method provides various models, in which the most significant model developed by stepwise backward-forward method with predictive internal q2=0.7589 and external predictivity (pred_r2 = 0.4752). In the presented model electrostatic descriptors play crucial role for activity. Electrostatic descriptor (E_137) indicates regions in which electron withdrawing groups are favourable and descriptor (E_939) represents electron rich or electron donating groups are advantageous in particular region. The counter map/ plot of this model further helps to understand the relationship of structural feature of derivative of quinoxaline and its biological activity this would be applied for designing of new potent antimalarial containing quinoxaline as lead.

3D QSAR analysis on quinoxaline derivatives as anti-malarial using K-nearest neighbour molecular field analysis

727-731In the present article, k nearest neighbour molecular field analysis (kNN-MFA) method was used to develop a three dimensional quantitative structure activity relationship (3D-QSAR) model. In this study 37 derivatives of quinoxaline having antimalarial activity were used. Sphere exclusion (SE) algorithm was used to create the biological activity data set in to into training and test set. For model generation kNN-MFA method has coupled with stepwise, simulated annealing and genetic algorithm this method provides various models, in which the most significant model developed by stepwise backward-forward method with predictive internal q2=0.7589 and external predictivity (pred_r2 = 0.4752). In the presented model electrostatic descriptors play crucial role for activity. Electrostatic descriptor (E_137) indicates regions in which electron withdrawing groups are favourable and descriptor (E_939) represents electron rich or electron donating groups are advantageous in particular region. The counter map/ plot of this model further helps to understand the relationship of structural feature of derivative of quinoxaline and its biological activity this would be applied for designing of new potent antimalarial containing quinoxaline as lead

Heterogeneous graphitic carbon nitrides in visible-light-initiated organic transformations

In recent years, g-C3N4 photocatalyst-mediated organic reactions have represented an important mode of chemical transformations and are expected to become a crucial field at the forefront of organic chemistry. Polymeric g-C3N4 as a heterogeneous catalyst has attracted great attention compared to other metal-based catalysts in photocatalytic applications because of its cost-effectiveness, good chemical stability, no heavy metal pollution, and eco-friendliness. In recent years, aerobic oxidation under visible-light has been identified as an attractive and fast-developing field in synthetic chemistry due to the simple operating procedure, easy work up and high efficiency. This review highlights carbon nitride-catalyzed visible-light-promoted strategies for the oxidation of alcohols, synthesis of esters, phenols, and sulfoxides, reduction of nitro compounds, the formation of carbonyl compounds, and several coupling reactions. However, g-C3N4 demands high temperature and O-2 pressure in addition to visible-light in the system to deliver the desired organic transformations. An alternative strategy may be to anchor organic dyes on the surface of heterogeneous catalysts for mild reaction conditions. The more challenging reaction is the reduction, since investigations related to the selective photoreduction of organic substrates are limited in comparison with photocatalytic selective oxidation; specifically, g-C3N4 is restricted to nitro compounds predominantly. Attempts can be made to enhance the selectivity in reduction by modifying surfaces, changing external conditions, forming composites, etc