Synthesis, characterization and evaluation of antiinflammatory properties of novel α, β-unsaturated ketones

Purpose: To prepare and characterize alicyclic aromatic chalcone derivatives, and study their antibiotic and anti-inflammatory properties.Methods: Claisen-Schmidt (aldol condensation) base-catalyzed condensation was used for preparation of chalcone derivatives (compounds I - IV), and the products were characterized using ultraviolet-visible spectroscopy (UV), FT-IR spectroscopy, proton nuclear magnetic resonance (1H-NMR), carbone 13CNMR and mass spectroscopy (MS). The antibacterial effect of the compounds was determined against Baci. cereus, Staph. Aureus, E. coli, and Pseudomonas Aeruginosa. In addition, their anti-inflammatory effects were assayed using cotton granule-induced granuloma in mice. The results were compared with those for diclofenac, a standard drug. The synthesized derivatives were subjected to theoretical studies on their stabilities, and some chemical parameters were calculated using density function theory [DFT].Results: Using Claisen-Schmidt reaction, it was possible to prepare stable chalcone derivatives, such as derivatives of 2-(3-phenyl  acryloyl)cyclopentan-1-one, with good results. Depending on the substituted group, it was also shown that the derivatives had effective biological effects. Compound IV displayed a noticeable antibacterial effect against Staph. aureus and E. coli. The prepared chalcone derivatives exerted markedly variable anti-inflammatory effects.Conclusion: These results indicate that Claisen-Schmidt reaction is not limited to the preparation of chalcone derivatives from diphenyl structures  only. Stable alicyclic aromatic structures can also be used. This results in derivatives with good biological effects. Keywords: Chalcones, Claisen-Schmidt, Anti-inflammatory effects, Granuloma, Aldol Condensatio

SYNTHESES AND ANTIOXIDANT ACTIVITIES OF SOME HYDROXY DIMETHOXY CHALCONE DERIVATIVES

Four (4) hydroxy dimethoxy chalcones derivatives were synthesized by Claisen-Schmidt condensation of hydroxyacetophenone with 3,4-dimethoxybenzaldehyde using conventional method and grinding technique. The synthesized compounds were characterized by spectroscopy (IR, 1H-NMR and 13C-NMR). Synthesis of the hydroxy dimethoxy chalcone using grinding method is better than the conventional method. The synthesis using grinding method require a low concentration base, shorter reaction (15min) and higher yield (70-84%).  The antioxidant activity of the compounds was determined by DPPH method, showed that  2',5'-dihydroxy-3,4-dimethoxy chalcone have the highest antioxidant activity.Key word: hydroxy dimethoxy chalcone, Claisen-Schmidt condensation, grinding, DPPH metho

A Review of Synthesis Methods of Chalcones, Flavonoids, and Coumarins

Chalcones are the principal precursors for the biosynthesis of flavonoids and isoflavonoids. A three-carbon α, β-unsaturated carbonyl system constitutes chalcones. Chalcones are the condensation products of an aromatic aldehyde with acetophenones in attendance of catalyst. A lot of methods and schemes have been reported for the synthesis of these compounds. Amongst all, Aldol condensation and Claisen-Schmidt condensation reactions are the most cited synthetic protocols in literature, nevertheless, Suzuki reaction, Witting reaction, and Photo-Fries rearrangement have also been utilized as synthetic protocols towards the chalcone framework. Several catalysts have been developed in the synthesis of the chalcone framework among which SOCl2 natural phosphate, lithium nitrate, amino grafted zeolites, zinc oxide, water, K2CO3, PEG400, silica sulfuric acid, ZrCl4, and ionic liquid are the most cited ones. The development of better synthetic techniques for the synthesis of α, β- unsaturated carbonyl compounds is still remaining high demand. Keywords: Chalcones, Aldol condensation, Claisen-Schmidt condensation, Suzuki reaction, Witting reaction, Photo-Fries rearrangement DOI: 10.7176/CMR/14-3-01 Publication date:August 31st 2022

3-(2-Fluoro­phen­yl)-1-(4-methoxy­phen­yl)prop-2-en-1-one

The title compound, C16H13FO2, was prepared from 4-methoxy­hypnone and 2-fluoro­benzophenone by a Claisen–Schmidt condensation reaction. The dihedral angle between the two benzene rings is 31.99 (2)°. In the crystal structure, mol­ecules are linked by weak inter­molecular C—H⋯O hydrogen bonds along [010]

Tandem aza-Claisen rearrangement and ring closing metathesis reactions: the stereoselective synthesis of functionalised carbocyclic amides

A one-pot, tandem process has been developed for the efficient synthesis of functionalised carbocyclic amides. A substituted cyclopentenyl trichloroacetamide was synthesised using a tandem thermal aza-Claisen rearrangement and RCM process, while an analogous cyclohexenyl trichloroacetamide was generated with high diastereoselectivity using a tandem MOM-ether directed metal-catalysed aza-Claisen rearrangement and RCM process

Versatile synthesis of dissymmetric diarylideneacetones via a palladium-catalyzed coupling-isomerization reaction

peer reviewedAs a twofold Michael system, the diarylideneacetone core is of particular interest in organic synthesis and for therapeutic applications. To overcome the drawbacks of the classical Claisen-Schmidt protocol, a new methodology for the synthesis of dissymmetric (hetero)diarylideneacetones has been developed. Conditions were optimized with a Box-Behnken design of experiment. The milder reaction conditions allow the efficient preparation of fluorinated, or heteroaromatic, dissymmetric diarylideneacetones which cannot be obtained through the classical Claisen-Schmidt protocol. © Georg Thieme Verlag KG · Stuttgart · New York

Synthesis and characterization of new Oxazine , Thiazine and Pyrazol derived from chalcones

In this study, chalcones were synthesis by condensing 2-acetylpyridine with aromatic aldehyde derivatives in dilute ethanolic potassium hydroxide solution at room temperature according to Claisen-Schmidt condensation. After that, new heterocyclic derivatives such as Oxazine, Thiazine and Pyrazol were synthesis by reaction between chalcones with urea, thiourea and hydrazine hydrate respectively scheme 1. All these compounds wrer characterization by FTIR, 1H-NMR spectroscopy and elemental analysis

Microwave Assisted Synthesis, Characterization and Biological Study of Some Chalcone Compounds Derived from Phenyl Isothiocyanate

Chalcones are synthesized by Claisen-Schmidt condensation, which involves cross-aldol condensation of appropriate aldehydes and ketones by base catalyzed reaction, the new chalcone derivatives synthesized by the reaction aldehyde with their compounds. By microwave assisted synthesis, a considerable increase in the reaction rate has been observed and that too, with better yields. M.P., TLC, CHN, FTIR, NMR and MS spectroscopy has characterized all the synthesized compounds. The biological screening data of the synthesized compounds were also studied. Keywords: microwave, chalcone, antibacterial. DOI: 10.7176/CMR/11-3-05 Publication date:March 31st 201

Single-crystal X-ray diffraction study of novel pyrazole chalcone derived from 1-phenyl-3-p-tolyl-1H-pyrazole-4-carbaldehyde

143-146Novel pyrazole chalcone has been synthesized by reaction of phenyl-3-p-tolyl-1H-pyrazole-4-carbaldehyde and acetophenone by Claisen-Schmidt reaction in ethanol by microwave assisted method. It has been characterized by elemental analysis and spectroscopic (FTIR, 1H NMR and MS) studies. Crystal structure of the compound has been determined using single-crystal X-ray diffraction. Hydrogen-bonded chain is formed by C–H···O bonding enhanced by C–H···π interaction. Adjacent chains are connected through the π∙∙∙π interactions

Microwave-Assisted Claisen-Schmidt Condensation Reaction of Ethyl p-methoxycinnamate to Synthesize p-Methoxystyryl Ketone Derivatives and Evaluate Anti-inflammatory Activity of Synthetic Products

The rhizome of Kaempferia galanga has been known to contain ethyl p-methoxycinnamate (EPMC) (1) as a main component, which has anti-inflammatory properties. Previously we have reported the structural modification of EPMC (1) to form another ester, nitrostyrene, and cinnammamide derivatives and then studied their structure-activity relationships as anti-inflammatory agent. In continuing our research, in this paper, we report the microwave-assisted Claisen-Schmidt condensation of EPMC (1) to synthesize a series of p-methoxystyryl ketones followed by a study of their anti-inflammatory activity. The reaction begins with microwave-assisted cleavage oxidation of hydrolyzed product of EPMC, p-methoxycinnamic acid (2) with Ca(NO3)2 for the synthesis of p-methoxybenzaldehyde (3). Furthermore, 3 was reacted with acetophenone, ethyl methyl ketone and acetone via microwave-assisted Claisen-Schmidt condensation for the synthesis of (E)-1-(4-methoxyphenyl)-3-phenylprop-2-en-1-one (5a) (E)-1-(4-methoxyphenyl)pent-1-en-3-one (5b) and (E)-4-(4-methoxyphenyl)but-3-en-2-one (5c), respectively. The reaction products were characterized using spectroscopic techniques and were then tested for anti-inflammatory activity using in vitro anti-denaturation of protein assay. It was found that converting EPMC (1) to 5a and 5b reduced anti-inflammatory activity, while 5c retained anti-denaturation activity with an IC50 of 72.8 µg/ml