Anticonvulsant evaluation of 2-pyrazolines carrying naphthyl moiety: An insight into synthesis and molecular docking study

A series of N-substituted-3-(napthalen-2-yl)-5-substituted phenyl-4,5-dihydropyrazole-1-carbothioamide derivatives (4a-n) were synthesized with the view of structural requirements of pharmacophore for potential anticonvulsant agents. The synthesized compounds were assayed intraperitoneally (i.p.) and subcutaneously (s.c.) in mice against seizures induced by MES and scPTZ methods, respectively.Neurologic deficit was evaluated by rotarod method. Among the tested compounds, 4g, 4i, 4j and 4n emerged as the most active molecule in the MES model at a dose of 30 mg/kg at 0.5h comparable to standardscarbamazepine and phenytoin. In the scPTZ test,4e and 4l were found to be most active compounds at the lowest dose of 30 mg/kg at 0.5h, in the management of the convulsive disorder. Molecular docking studies of the titled compounds were also donewith 3D crystal structure of human cytosolic branched chain amino transferase (hBCATc) enzyme and compound 4e was found to have five hydrogen bond interactions with the most important active site residues.In neurotoxicity studies, except compounds 4b, 4c, 4h and 4k, rest of the compounds showed no sign of toxicity.

Design, synthesis, and molecular docking study of benzothiazolotriazine derivatives for anticonvulsant potential.

A series of newer benzothiazolotriazine derivatives (4a-k) was designed, synthesized, and characterized as anticonvulsant agents against the two classically used MES and scPTZ animal models. The synthesized derivatives were tested in vivo in both the animal models, followed by a neurotoxicity study by the rotarod method. Compound 4e, 8-chloro-4-(2-chlorocyclohexa-1,5-dien-1-yl)-2-((4-methoxybenzyl)thio)-10aH-benzo[4,5]thiazolo[3,2a][1,3,5]triazine was found most promising among the series in both the animal models, with no neurotoxicity. From this it may be confirmed that the presence of a methoxy (OCH3 ) group at the lipophilic aryl ring was showing high anticonvulsant potency. In the molecular modeling study, compound 4e (docking score = -8.70) showed important hydrogen bond interaction with the amino acids LYS 329, SER 137, GLY 136 and π-π interactions with PHE 189 at the active site of GABA-AT. These derivatives can be further explored for the development of newer/novel anticonvulsant agents.

5,6-Dihydropyrimidine-1(2H)-carbothioamides: Synthesis, in vitro GABA-AT screening, anticonvulsant activity and molecular modelling study.

Even after considerable advances in the field of epilepsy treatment, convulsions are inefficiently controlled by standard drug therapy. Herein, a series of pyrimidine-carbothioamide derivatives 4(a-t) was designed as anticonvulsant agents by doing some important structural modifications in well-known anticonvulsant drugs. Two classical animal models were used for the in vivo anticonvulsant screening, maximum electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) models; followed by motor impairment study by rotarod method. The most active compound 4g effectively suppressed seizure effect in both the animal models with median doses of 15.6 mg/kg (MES ED50), 278.4 mg/kg (scPTZ ED50) and 534.4 mg/kg (TD50) with no sign of neurotoxicity. Furthermore, in vitro GABA-AT enzyme activity assay of 4g showed inhibitory potency (IC50) of 12.23 µM. The docking study also favored the animal studies.

Design, synthesis and evaluation of newer 5,6-dihydropyrimidine-2(1H)-thiones as GABA-AT inhibitors for anticonvulsant potential.

Several new 5,6-dihydropyrimidine-2(1H)-thione derivatives have been prepared and investigated for their potencies for anticonvulsant activity against maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) test in mice. The acute neurotoxicity was measured by rotarod test. Compounds 3c and 3l were found active in both of the animal models. Further, in vitro GABA-AT enzyme activity assay was carried out to investigate the possible mechanism of action through GABA-AT inhibition. The most potent compounds 3c and 3l showed inhibitory potency (IC50) of 18.42µM and 19.23µM, respectively. The molecular modeling was performed for all the synthesized compounds. The docking results were found in concordant with the observed animal studies.

Design, Synthesis, and Docking Study of Pyrimidine-Triazine Hybrids for GABA Estimation in Animal Epilepsy Models.

A series of new pyrimidine-triazine hybrids (4a-t) was designed and synthesized, from which potent anticonvulsant agents were identified. Most of the compounds exhibited promising anticonvulsant activity against the maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) tests, along with minimal motor impairment with higher safety compared to the standard drugs, phenytoin and carbamazepine. In the series, 5-(4-(4-fluorophenyl)-6-(4-hydroxyphenyl)-2-thioxo-5,6-dihydropyrimidin-1(2H)-yl)-1,2-dihydro-1,2,4-triazin-3(6H)-one (4o) and 5-(6-(4-hydroxy-3-methoxyphenyl)-4-(4-hydroxyphenyl)-2-thioxo-5,6-dihydropyrimidin-1(2H)-yl)-1,2-dihydro-1,2,4-triazin-3(6H)-one (4s) emerged as most potent anticonvulsant agents with median doses of 22.54 and 29.40 mg/kg (MES ED50 ), 285.02 and 293.42 mg/kg (scPTZ ED50 ), and 389.11 and 412.16 mg/kg (TD50 ), respectively. Docking studies were also performed for all synthesized compounds to get insight into the binding pattern toward the GABAA receptor as a possible mechanism of their anticonvulsant action, and in silico ADME studies were carried out to predict the safety and stability of the molecules. The increased GABA level in the experimental animals in the neurochemical estimation assay confirmed their GABAergic modulating activity. The most potent compounds were also evaluated for their neurotoxic and hepatotoxic effects. Fortunately, they did not show any sign of neurotoxicity or hepatotoxicity, suggesting that they have a broad spectrum of anticonvulsant activity with a large safety margin. Together, this research suggested that 4o and 4s may serve as leads in the discovery and development of new anticonvulsant drugs.

Synthesis, molecular docking and anti-diabetic evaluation of 2,4-thiazolidinedione based amide derivatives.

A series of thiazolidinedione based amide derivatives were designed, synthesized and docked against the PPARγ receptor target. 11 compounds from the series with good glide scores were selected for in vivo antidiabetic study based on streptozotocin induced diabetic rat model. It was observed that 4 compounds (6c, 6e, 6m &6n) showed significantly good antidiabetic activity in comparison to rosiglitazone and pioglitazone as reference drugs. Compound 6c appeared as the most potent derivative in lowering blood glucose level and showed excellent interaction with SER 342, ILE 281, pi-pi interaction with ARG 288 and halogen bond interaction with LYS 367. Further, PPARγ transactivation and gene expression studies of compound 6c were carried out to investigate the possible mechanism of action through PPARγ modulation. Compound 6c exhibited 53.65% transactivation and elevated PPARγ gene expression by 2.1 folds. The biochemical parameters (AST, ALT and ALP levels) were found within the range with no noteworthy damage to liver.

Therapeutic journey of 2,4-thiazolidinediones as a versatile scaffold: An insight into structure activity relationship.

Thiazolidinedione is an important heterocyclic ring system, a pharmacophore and a privileged scaffold in medicinal chemistry; is a derivative of thiazolidine ring which came into existence for its role as antihyperglycemic agent and a specific ligand of PPAR's (Peroxisome proliferator activated receptor). Exhaustive research has led to determination of its vast biological profile with wide range of therapeutic applications. This review covers recent pharmacological advancements of thiazolidinedione moiety along with structure activity relationship so as to provide better correlation among different structures and their receptor interactions.

Design, synthesis, anticonvulsant evaluation and docking study of 2-[(6-substituted benzo[d]thiazol-2-ylcarbamoyl)methyl]-1-(4-substituted phenyl)isothioureas.

In this paper, we report the synthesis of 2-[(6-substituted benzo[d]thiazol-2-ylcarbamoyl)methyl]-1-(4-substituted phenyl)isothiourea derivatives (4a-y) carrying active pharmacophores essential for anticonvulsant activity. The anticonvulsant activity was evaluated in vivo by maximal electroshock (MES) test and subcutaneous pentylenetetrazole (scPTZ) test in mice. Most of the compounds showed promising anticonvulsant activity. The most active compounds 4b and 4q were found active in both MES and scPTZ models, without signs of neurotoxicity. Compound 4b showed the moderate change in SGOT and alkaline phosphatase level as compared to control. Compounds 4b and 4w were also found to elevate GABA levels in the olfactory lobe, mid brain, medulla oblongata and cerebellum regions of rat brain. In molecular docking study, the title compounds exhibited good binding properties with epilepsy molecular targets such as GABA-A. Structure-activity relationships are also elaborated along with the analysis of lipophilicity. The results suggested that compound 4b is likely to have varied mechanisms of action including voltage-gated ion channel inhibition and modulating GABAergic action.