L-Proline-Catalyzed Synthesis of Phthalimide Derivatives and Evaluation of Their Antioxidant, Anti-Inflammatory, and Lipoxygenase Inhibition Activities

Shagufta Perveen,Raha Orfali

doi:10.1155/2018/5198325

Abstract

A study was planned to synthesize the phthalimide derivatives as phthalimides have versatile biological activities. To synthesize the phthalimide derivatives, initially the reaction was optimized with various catalysts, and L-proline was found to be the best catalyst as it provided excellent yield. A series of phthalimide derivatives was synthesized by facile one-top reaction of phthalic acid with aryl amines under mild reaction conditions in the presence of L-proline as catalyst. Products were obtained in excellent yields and structurally characterized by 1H, 13C NMR, and mass spectral data. Products 1–7 were evaluated for antioxidant, anti-inflammatory, and lipoxygenase enzyme inhibition activities. Compounds 1 and 4 showed potent antioxidant activity under DPPH with IC50 values 27.3 and 25.0 μM when compared with the standard BHA (IC50 = 44.2 μM), respectively. Compounds 1 and 4 further showed strong lipoxygenase inhibition activity with IC50 values 21.34 and 20.45 μM when compared with standard baicalein (IC50 = 22.60 μM), respectively. Compound 2 was found to be promising and about equal to the used standard aspirin in the inhibition of bovine serum albumin denaturation, while other compounds showed weak-to-moderate % inhibition.

Highlights

Heterocyclic compounds have been found to possess important physiological and pharmaceutical properties [1]
Due to wide range of applications in medicinal chemistry, interest is increasing in the synthesis and biological activities of phthalimides and its derivatives
We planned to synthesize the N-aryl phthalimides from phthalic acid and aryl amines and evaluate them biologically to find out the novel lead candidates

Summary

Introduction

Heterocyclic compounds have been found to possess important physiological and pharmaceutical properties [1]. Phthalimides and their N-substituted derivatives belongs to the imide ring containing heterocyclic class of compounds which possess extensive biological activities [2]. Due to wide range of applications in medicinal chemistry, interest is increasing in the synthesis and biological activities of phthalimides and its derivatives. We report the synthesis of N-aryl phthalimides 1–7 and their biological screening for antioxidant and anti-inflammatory potentials. All the synthesized compounds have significant antioxidant active, whereas compounds 1 and 4 showed potent antioxidant potential, much better potential as compare to the standard BHA

Materials and Methods

Biological Assays

In Vitro Antioxidant Activities

Results and Discussion