en |
Synthesized 2-Substituted-3-Phenylthiazolidine-4-ones as Potent Antioxidants and Antidiabetic Agents
Sen, Sandip; De, Biplab & Easwari, Trichy Siva
Abstract
Purpose: To employ intramolecular cyclization of Schiff bases of pyrazole-4-carboxaldehydes to form
thiazolidine-4-ones and determine the antioxidant and antidiabetic activity of the synthesized
compounds. Methods: The Schiff bases were obtained upon reaction between the electrophillic carbon atom of
pyrazole-4-carboxaldehyde and the nucleophillic nitrogen atom of the amine. Preparation of thiazolidine-
4-one was preceded by attack of sulphur nucleophile of thioglycollic acid on imine carbon followed by
intramolecular cyclization using acid catalyst. In vitro antioxidant activity was determined by 1, 1-
diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay method using ascorbic acid as standard.
Evaluation of antidiabetic activity was carried out in streptazotocine-induced diabetes in Wister rats
using rosiglitazone as reference drug. Blood glucose levels were estimated by GOD-POD kit. Serum
biochemical parameters like total cholesterol, triglyceride, urea, creatinine and total protein level were
also measured. Results: Compounds 7a, 7b, 7c, 7e, 7j showed higher IC50 [Half maximal inhibitory concentration]
values than the reference antioxidant, ascorbic acid. On the 21st day of treatment, there was significant
fall and rise blood glucose level and body weight, respectively, compared to the anti-diabetic standard.
There was decrease in serum cholesterol, triglyceride, creatinine and urea levels while high density
lipoprotein (HDL) level and total protein levels increased after 21 days of treatment. Compared to
rosiglitazone, compounds 7a, 7b, 7c, 7h, 7j showed stronger significant antidiabetic effect in
hyperglycemic rats due, probably, to the presence of thiazolidine-4-one nucleus as well as parasubstitution
on phenyl ring.
Conclusion: The 2-(3-Methyl-1H-pyrazol-4-yl)-3-phenylthiazolidin-4-ones possess potent antioxidant
and antidiabetic activity but further studies are required to develop them for clinical use.
Keywords
Pyrazole-4-carboxaldehydes; Thiazolidine-4-one; Antioxidant; Anti diabetic
|