Novel Mannich-bases as Potential Anticonvulsants: Syntheses, Characterization and Biological Evaluation

Title:Novel Mannich-bases as Potential Anticonvulsants: Syntheses, Characterization and Biological Evaluation

Volume: 17 Issue: 3

Author(s): Amit K. Keshari , Aseem Tewari, Shweta S. Verma and Shailendra K. Saraf *

Affiliation:

• Faculty of Pharmacy, Babu Banarasi Das Northern India Institute of Technology, Sector-2, Dr. Akhilesh Das Nagar, Faizabad Road, Lucknow, 226028, U.P.,India

Keywords: Anticonvulsant activity, benzothiazepine, benzoxazepine, claisen-schmidt condensation, isoniazid induced convulsion model, mannich bases, MES test.

Abstract: Background: Mannich bases are known to be an important pharmacophore or bioactive leads in the synthesis of various potential agents that have a variety of therapeutic activities like anticancer, antipsychotic, anticonvulsant, antimalarial, anti-inflammatory, antibacterial and so forth. Thus, in the present research, conjugation of moieties like 1,5-benzoxazepines and 1,5-benzothiazepines with secondary amines like piperazine, methyl piperazine and morpholine was carried out in a Mannich base with an anticipation of good anticonvulsant activity.

Objective: Synthesis, characterization, structure activity relationship and anticonvulsant activity of the Mannich bases of 1,5-benzothiazepine and 1,5-benzoxazepine derivatives.

Methods: All the derivatives were synthesized in three steps. In the first step, substituted 4-hydroxy chalconylbenzene was synthesized by the reaction of 4-hydroxyacetophenone and substituted benzaldehyde, in the presence of potassium hydroxide. In the second step, 2,3-dihydro- 1,5- benzothiazepines and 2,3-dihydro-1,5-benzoxazepines were synthesized by the reaction of 2- thio/aminophenol with chalcones in the presence of glacial acetic acid. In the third step, these compounds finally underwent Mannich reaction with different secondary amines to the respective title compounds. All the synthesized derivatives were characterised and evaluated for anticonvulsant activity using MES (Maximal Electroshock Induced Seizure) and INH (Isoniazide Induced Convulsion) models.

Results: The synthesized derivatives were found to be more active in the MES model than INH model, with phenytoin and diazepam being the standards respectively. Accordingly, the mode of action of the synthesized compounds may be similar to phenytoin. The methyl piperazine containing compound, at a dose of 30 mg/kg., was found to be the most active and promising compound in the series.

Conclusion: The benzothiazepine derivatives showed better anticonvulsant activity than the benzoxazepines derivatives.

Cite this article as:

Keshari K. Amit , Tewari Aseem, Verma S. Shweta and Saraf K. Shailendra *, Novel Mannich-bases as Potential Anticonvulsants: Syntheses, Characterization and Biological Evaluation, Central Nervous System Agents in Medicinal Chemistry 2017; 17 (3) . https://dx.doi.org/10.2174/1871524917666170717113524