Alumina-K₃PO₄ Solid Supported Microwave Synthesis of 1, 3-diaryl-2- propene-1-one Derivatives as a Prominent Antioxidant Scavenger

Abstract

Background: The various industrial processes have diverse effect on environment through pollution. In view of these observations, some environmentally benign synthetically protocols have developed under green chemistry. For rapid and sustainable synthesis the microwave irradiation (MI) has gained popularity as a powerful tool compared to conventional synthesis. The present study describes the synthesis of novel substituted 1, 3-diaryl-2-propene-1-one derivative using alumina supported K3PO4-MWI combination. Objective: Chalcones are the important compounds and widely spread in nature such as in fruits, vegetables, tea, spices etc. The 2’-hydroxy derivative of chalcones play an important role in synthesis of bioactive compounds. The present communication deals with a convenient and rapid synthesis of 1, 3-diaryl-2-propene-1-one under the support of alumia-tripotassium phosphate and microwave irradiation. Our efforts are focused on the introduction of typical and easier route for synthesis of title compounds using microwave. All synthesized chalcones have been screened and evaluated for the antioxidant activity by DPPH and nitric oxide radical scavenging. Some of these compounds found to be more potent scavengers and may lead to the development of new class of antioxidants. Method: The α, β-unsaturated carbonyl functionality contain two electrophilic centers allowing them to undergo addition and cyclisation reaction with different nucleophiles. In the literature survey, we found that Chalcones were synthesized using tripotassium phosphate catalyst under refluxing by conventional method. A novel method for the synthesis of 1, 3-diaryl-2-propene-1-one via Claisen –Schmidt has been introduced by reacting substituted 2’- hydroxyl acetonaphthones with substituted aromatic aldehydes under the support of basic alumina –tripotassium phosphate via microwave radiations. Formation of corresponding Chalcones was confirmed by spectral studies followed by their screening for antioxidant activity. The scavenging activity is expressed in terms of % inhibition and IC50 value (μg/ml). Results: The structures of newly synthesized Chalcones were confirmed and in good agreement with obtained spectral analysis such as IR, NMR, Mass and elemental analysis. Commercially available basic alumina and tripotassium phosphate in combination of microwave were utilized and found to be effective, convenient route for the synthesis of 1, 3-diaryl-2-propene-1-one derivatives with desirable yields in short reaction time (5-12 min). The results of antioxidant activity revealed that the IC50 value for compounds 3a, 3d, 3e, 3f, 3g, 3h, 3j, 3l and 3nare lower than that of standard ascorbic acid to scavenge DPPH radical. This indicates that these compounds are more significant scavenger in comparison with standard drug. On the other hand the compounds 3a, 3b, 3c, 3d, 3g, 3l and 3n are more potent scavenger for NO free radical. Conclusion: We have introduced an efficient, ecofriendly, simple and fast microwave assisted method using basic alumina-tripotassium phosphate for synthesis of 1, 3-diaryl-2-propene-1-one derivatives. Microwave irradiation provides an effective way for the preparation of Chalcones in terms of several advantages as simple procedure, short reaction time, milder reaction condition, cleaner reaction and excellent yield. The scavenging activity of chalcones against DPPH and NO free radicals showed excellent properties of antioxidants.

Synthesis, characterization, antimicrobial screening and cytotoxic properties of Cu(II) and Zn(II) complexes with bidentate hydroxylated 1,3-diaryl-2-propene-1-ones ligand

“…The presence of α,β-unsaturated carbonyl system makes chalcone huge important in organic chemistry. 10 The versatility of chalcones arises from their distinctive combination of functional groups. Chalcone and their derivatives can act as chelating agents towards metals to form stable complexes.…”

Naphthyl‐Based Chalcone Derivatives: A Multifaceted Player in Medicinal Chemistry

“…Patil et al reported the series of chalcone derivatives 109 a-n (Figure 19) by microwave-assisted method. [158] Some of these substances were discovered to be substantial scavengers and showed stronger antioxidant activity. The results showed that the IC 50 By using the two-directional Claisen-Schmidt condensation, numerous novel bis-hydroxy derivatives of chalcones 110 a-h (Figure 19) were produced by Khazaei-Poul et al [159] The in vitro antioxidant activity of bis-hydroxychalcones was measured using DPPH radical scavenging activity, with IC 50 values ranging from 134 to 1626 μM compared to ascorbic acid.…”

“…Patil et al . reported the series of chalcone derivatives 109 a – n (Figure 19) by microwave‐assisted method [158] . Some of these substances were discovered to be substantial scavengers and showed stronger antioxidant activity.…”

Optimization of pyridine based Schiff bases: Design, synthesis and determination of anti-inflammatory, antioxidant and antimicrobial activity

“…The use of catalyst for the synthesis of imine suffers from several demerits such as harsh reaction conditions, tedious work up in the separation of product and catalyst. Recently the use of K3PO4 13 encouraged us to use it for the syntheses of imines in combination with microwave irradiation methods. The tripottasium phosphate faces the reaction between 2-amino pyridine and different substituted benzaldehyde to give Schiff bases (Scheme 1).…”

“…12 Therefore, this technique presently known as etechnique as easy, ecofriendly, environmentally being and economic. 13 Following these observations and with the aim of our research has concerned on achieving reasonable yields of the synthesized Schiff bases from 2-aminopyridine. In the present work we plan to synthesize novel series of Schiff bases (3a to 3l) derived from 2-amino pyridine with different substituted benzaldehydes by using alumina-anhydrous tripottasium phosphate under microwave irradiation.…”