Claisen-Schmidt Condensation Reaction Research Articles

Incorporation of nanosized ZnWO4 and Fe3O4 on graphitic carbon nitride to fabricate a novel, highly active magnetically recoverable catalyst in Claisen–Schmidt condensation

Herein we outline a facile and viable approach for successful anchoring of ZnWO4 and Fe3O4 nanoparticles on graphitic carbon nitride (g-C3N4) through ultrasonication and microwave irradiation. The as-synthesised nanocomposite, g-C3N4–Fe3O4–ZnWO4, was characterised using Fourier transmission infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, vibrating-sample magnetometry, and X-ray photoelectron spectroscopy techniques. The nanocomposite exhibited appreciable catalytic performance in the Claisen–Schmidt condensation reaction between benzaldehyde and acetone producing dibenzalacetone with excellent yields. The as-prepared catalyst demonstrated excellent magnetically recyclable property for seven successive runs. The presence of g-C3N4 in the nanocomposite g-C3N4–Fe3O4–ZnWO4 played a significant role in promoting the catalytic activity due to its inherent basic nature and efficient grafting of the substrates onto the g-C3N4 sheets.

Growth and Characterization of (E)-1-(5-Chlorothiophene-2-Yl)-3-(4- Dimethylamino)Phenyl)Prop-2-En-1-One, Novel NLO Single Crystal

A novel NLO compound (E)-1-(5-chlorothiophene-2-yl)-3-(4-dimethylamino) phenyl) prop-2-en-1-one has been synthesized by adopting claisen schmidt condensation reaction method and the single crystals are grown using slow solvent evaporation technique. The FT-IR spectrum confirms the various functional groups present in the compound. The crystal structure was studied by XRD method, which reveals that the compound crystallizes in Monoclinic crystal system with a space group P21/n and the corresponding lattice parameters are a = 7.595 (2) Å, b = 17.441 (4) Å, c = 10.917 (3) Å, α = 90o, β = 102.500 (12)o, γ = 90o. UV-Visible spectrum shows that the crystal is transparent in the entire visible region. Refractive index of the crystal was determined using Brewster’s angle method. Thermal stability of the material was determined from TG/DTA test. The Second harmonic generation efficiency of the crystal was estimated using NLO test and the efficiency was found to be 0.84 times that of UREA.

Design, synthesis and biological evaluation of new steroidal β-triazoly enones as potent antiproliferative agents

β-Triazoly enones are biologically interesting scaffolds, incorporation of such scaffolds into the steroid nucleus may generate new bioactive steroids and further enrich structural types of steroids. In this work, a series of new steroidal β-triazoly enones were synthesized based on click chemistry and Claisen–Schmidt condensation reaction and further evaluated for their antiproliferative activity against a panel of cancer cells. Most of these compounds showed better potency against PC-3 and MGC-803 cells. Particularly, compound 5a inhibited PC-3 and MGC-803 cells potently with the IC50 values of 1.61 and 1.16 μM, respectively, and was less toxic toward GES-1 with an IC50 value of 20.72 μM. Further mechanistic studies showed that compound 5a inhibited migration and invasion of MGC-803 and PC-3 dose-dependently. Treatment with compound 5a varied mRNA levels and protein expression of EMT markers in both cells. Collectively, the steroidal β-triazoly enones could be potentially utilized to develop new anticancer agents with the ability of inhibiting cell migration and invasion.

Synthesis and characterization of new 4,5-dihydropyrazol-1-yl derivatives

In this study, first, a series of chalcone compounds S1–S6 were synthesized from various acetophenone derivatives (acetophenone, p-methyl acetophenone, and p-methoxy acetophenone) and aromatic aldehyde derivatives (benzaldehyde, p-methyl benzaldehyde, and p-methoxy benzaldehyde) by the Claisen–Schmidt condensation reaction. These S1–S6 compounds were then used in the preparation of 4,5-dihydropyrazol-1-yl derivatives S7–S15. Finally, four new compounds S16–S19 were synthesized from compound (S7, S8, S9, and S12) and 2,4-dinitrophenylhydrazine. Therefore, three known and ten new heterocyclic compounds were synthesized and completely characterized using 1H NMR, 13C NMR, IR, and elemental analysis.

Synthesis of new 6-substituent 2-phenyl and 2-(furan-2-yl)-3-phenyl-quinoline-4-carboxylic acid derivatives

A synthesis of substituted quinolines has been achieved by the Doebner reaction which is a three component coupling of arylaldehyde, p-amino-acetophenone and phenyl pyruvic acid. The products of 2,3-diary-6-acetyl-quinoline-4-carboxylic acids were obtained by Claisen Schmidt condensation reaction with aldehydes in the presence of sodium hydroxide in order to give the corresponding α,β-unsaturated carbonyls. The substituted α,β-unsaturated carbonyls were condensed with urea, thiourea, hydrazine, phenyl hydrazine, semicarbazide hydrochloride and ethanolamine to synthesized 2-pyrimidinone, 2-pyrimidinethion, pyrazoline-1-phenyl, pyrazoline, pyrazoline-1-carboxamide and 1,4-oxazepines derivatives, respectively, with good yields. The purity and identities of products were elucidated through thin layer chromatography (TLC), melting point and spectroscopic data (IR, 1H NMR, 13C NMR and LC-Mass).

Introduction of amino moiety enhances the inhibitory potency of 1-tetralone chalcone derivatives against LPS-stimulated reactive oxygen species production in RAW 264.7 macrophages

The design and synthesis of a series of thirty-two halogenated 1-tetralone or 6-amino-1-tetralone chalcone derivatives was achieved by the Claisen-Schmidt condensation reaction and were evaluated for their inhibitory effects against ROS production in LPS-stimulated RAW 264.7 macrophages. It was observed that the introduction of amino moiety into 1-tetralone skeleton greatly increased the inhibitory potency compared to corresponding 1-tetralone chalcones. Among the synthesized compounds, compound 18 which consists of 6-amino-1-tetralone skeleton together with o-fluorobenzylidene showed the most potent ROS inhibitory effect with IC50 value of 0.25 ± 0.13 µM. SAR analysis revealed that amino moiety at the 6th position of 1-tetralone chalcones have an important role for exerting the greater ROS inhibitory potency in LPS-stimulated RAW 264.7 macrophages than those exhibited by 1-tetralone chalcones alone.

Synthesis of Chalcone Using LDH/Graphene Nanocatalysts of Different Compositions

Layered double hydroxides (LDH) or their derived mixed oxides present marked acid-base properties useful in catalysis, but they are generally agglomerated, inducing weak accessibility to the active sites. In the search for improving dispersion and accessibility of the active sites and for controlling the hydrophilic/hydrophobic balance in the catalysts, nanocomposite materials appear among the most attractive. In this study, a series of nanocomposites composed of LDH and reduced graphene oxide (rGO), were successfully obtained by direct coprecipitation and investigated as base catalysts for the Claisen–Schmidt condensation reaction between acetophenone and benzaldehyde. After activation, the LDH-rGO nanocomposites exhibited improved catalytic properties compared to bare LDH. Moreover, they reveal great versatility to tune the selectivity through their composition and the nature or the absence of solvent. This is due to the enhanced basicity of the nanocomposites as the LDH content increases which is assigned to the higher dispersion of the nanoplatelets in comparison to bulk LDH. Lewis-type basic sites of higher strength and accessibility are thus created. The nature of the solvent mainly acts through its acidity able to poison the basic sites of the nanocatalysts.

SYNTHESIS, ANTIBACTERIAL, ANTIFUNGAL ANTITUBERCULAR ACTIVITIES AND MOLECULAR DOCKING STUDIES OF NITROPHENYL DERIVATIVES

Infectious diseases are one of the common problems encountered globally. Even though there are a number of drugs available in the market for the treatment of infectious diseases, still many new molecules are required due to the problems with the existing drugs. Hence we prepared a series of chalcones (A1-A10) containing nitrophenyl moieties by Claisen-Schmidt condensation reaction. All the ten compounds were characterized by IR, NMR, Mass spectroscopy and elemental analysis. The compounds were further screened for antitubercular activity employing MABA assay and antibacterial and antifungal activities by cup plate method against selected tubercular, bacterial and fungal organisms. The compound A9 displayed potent antitubercular activity with MIC 11.02±0.030, whereas the compound A3 showed superior antibacterial and antifungal activities. Further, molecular docking studies were performed on Thymidine Kinase (TMP) of Mycobacterium tuberculosis by employing AU autodocker. The docking scores were in association with the in vitro MABA results and also identified the potent nature of A9 with the docking score -6.7. This study helped to identify novel nitrophenyl derivatives against thymidylate kinase.

Synthesis of Some Novel Flavanones and Evaluation of Antioxidant Activities

The novel series of substituted flavanones were synthesized by reacting various 2-hydroxy chalcones. The intermediate 2-hydroxy chalcones were synthesized by Claisen-Schmidt condensation reaction. Flavanones were prepared by refluxing 2-hydroxychalcones in ethanol in presence of conc. H2SO4. All the synthesized compounds (RF1-RF9) were assigned on the basis of IR, 1H-NMR and MASS spectral data. These synthesized compounds were evaluated for their antioxidant activity by two different methods, DPPH and nitric oxide method. The compounds RF1, RF2, RF6, and RF7, RF8 showed very good activity when compared to the standard.

Graphene-induced hierarchical mesoporous MgO for the Claisen–Schmidt condensation reaction

Multistage mesoporous magnesium oxide prepared by a simple hydrothermal method has an ideal particle size, channel distribution, active crystal face, good catalytic activity and regeneration ability.

Anti-Trichomonas vaginalis activity of chalcone and amino-analogues.

Trichomoniasis is the most common non-viral sexually transmitted disease worldwide and can lead to serious consequences in reproductive health, cancer, and HIV acquisition. The current approved treatment present adverse effects and drug resistance data on this neglected parasitic infection is underestimated. Chalcones are a family of molecules that present biological applications, such as activity against many pathogenic organisms including protozoan pathogens. Chalcone (1) and three amino-analogues (2-4) were synthesized by Claisen-Schmidt condensation reaction and had their activity evaluated against the parasitic protozoan Trichomonas vaginalis. This bioassay indicated the presence and position of the amino group on ring A was crucial for anti-T. vaginalis activity. Among these, 3'-aminochalcone (3) presented the most potent effect and showed high cytotoxicity against human vaginal cells. On the other hand, 3 was not able to exhibit toxicity against Galleria mellonella larvae, as well as the hemolytic effect on human erythrocytes. Trophozoites of T. vaginalis were treated with 3, and did not present significant reactive oxygen species (ROS) accumulation, but induced a significantly higher ROS accumulation in human neutrophils after co-incubation. T. vaginalis pyruvate:ferredoxin oxidoreductase (PFOR) and β-tubulin gene expression was not affected by 3.

Structure determination and quantum chemical analysis of chalcone derivatives

The chalcone derivative with a naphthalene unit, (E)-1-(4-hydroxyphenyl)-3-(naphthalen-2-yl)-prop-2-en-1-one was synthesized using the Claisen Schmidt condensation reaction method. This compound crystallizes in the monoclinic space group P21/n, with cell parameters a = 8.7203 (14) Å, b = 12.5568 (19) Å, c = 12.9667 (19) Å, α = 90, β = 104.272 (4), γ = 90 and V = 1376.0 (4) Å3. The UV–Vis spectrum of the title compound and three more chalcone derivatives whose structures were already reported by the same group of authors, show that the crystals are transparent in the entire visible region. Molecular parameters were calculated using MOPAC 2016. The static first order hyperpolarizability of all the four compounds are found to be greater than that of urea indicating that all the compounds are NLO active and suitable for optical tuning applications.

A vacuum calcination route to high-surface-area MgO nanoplates for superior arsenate adsorption and catalytic properties

Porous MgO nanoplates with high surface area has been synthesized by a vacuum calcination route using industrially available Mg(OH)2 as the precursor. The vacuum calcination not only promoted the phase transformation of Mg(OH)2 to MgO at a low temperature (300 °C), but also inhibited the thermally-induced particle growth and pore coalescence, leading to the formation of MgO nanoplates with fine grain sizes (5.5 nm), ultrasmall pores (2–4 nm) and high surface area (390 m2 g−1). The as prepared MgO nanoplates exhibited superior arsenic adsorption properties with a maximum adsorption capacity of 481.0 mg g−1, as well as excellent catalytic activity for the Claisen-Schmidt condensation reaction.

Tổng hợp một số Chalcone có chứa nhóm Azide

In the paper, seven new azide chalcones 5a-5g were synthesized from 2,4-dihydroxyacetophenone in good yields via a 3-step procedure including selective O-alkylation with 1,2-dichloroethane, nucleophilic substitution with sodium azide and Claisen-Schmidt condensation reaction with different aldehydes 4a-4g. The structure of the azides chalcones was elucidated by spectroscopic methods such as NMR and HR-ESI-MS spectra.

Eco-friendly and simple synthesis of some non-natural flavones through chalcones

A distinctive feature of polyphenolics is the possession of biological properties such as antioxidant and antimicrobial activities. Simple synthesis and study about such important class of compounds and their analogs are very important to enhance the understanding of their role in human health and diseases. Accordingly, a series of chalcones (2a-f) have been synthesized by Claisen-Schmidt condensation reaction with required acetophenones and aromatic aldehydes in high yields. The conversion of chalcones to the corresponding flavones (1a-g) taking minimal amount of dimethyl sulfoxide with iodine in presence of sulfuric acid was carried out under microwave conditions in high yields.

SYNTHESIS AND ANTIPROLIFERATIVE ACTIVITY OF FLAVONOID DERIVATIVES: EFFECT OF B-RING SUBSTITUTION

Flavones, flavonols, flavanones and isoflavones constitute four important categories of naturally occurring flavonoids. These compounds possess good antiproliferative activity and can act as adjuvants to existing anticancer therapy. We have synthesized twenty synthetic flavonoids including flavones, flavonols, flavanones and isoflavones using Claisen-Schmidt condensation, Baker-Venkataraman rearrangement and related reactions. The synthesized compounds were evaluated for antiproliferative activity against MCF-7, K562 and HepG2 cell lines. Flavanones showed good activity against HepG2 cell lines whereas some flavones and isoflavones were active in inhibiting the growth of K562 and MCF-7 cell lines. The study underlines the importance of electron rich substituents on the B-ring of synthetic flavonoids.

Synthesis, growth and characterization of a new NLO active chalcone derivative - 4-chloro-N-{3-[(2E)-3-(methoxyphenyl)prop-2-Enoyl]phenyl}benzamide monohydrate

Single crystal of a new Chalcone derivative “4-chloro-N-{3-[(2E)-3-(methoxyphenyl)prop-2-enoyl]phenyl}benzamide(CMPB)” was grown by slow evaporation method using Claisen-Schmidt and Schotten-Boumann Condensation reaction. XRD analysis was carried out to determine the structure, inter and intramolecular interactions of the compound. FTIR spectrum was taken to confirm the presence of functional groups in the compound. The number of protons and carbons present in the compound were determined by 1H and 13C NMR spectral analysis. The absorption and emission spectrum were analyzed by UV–Vis and Photoluminescence spectral analysis. The band gap energy was calculated using the cut off wavelength obtained from the UV–Vis spectrum. Thermal analysis TG/DSC was carried out to find the stability, melting point and decomposition point of the title compound. The SHG test shows that the efficiency of the crystal is 1.4 times as that of KDP which indicates the title compound has good NLO activity.

Crystal structure and theoretical studies of two π-conjugated fused-ring chalcones: (E)-1-(anthra-cen-9-yl)-3-(9-ethyl-9H-carbazol-3-yl)prop-2-en-1-one and (E)-1-(anthracen-9-yl)-3-[4-(9H-carbazol-9-yl)phen-yl]prop-2-en-1-one.

The title chalcones, C31H23NO and C35H23NO, were synthesized via Claisen-Schmidt condensation reactions. Both structures were solved and refined using single-crystal X-ray diffraction data and optimized at the ground state using the density functional theory (DFT) method with the B3LYP/6-311++G(d,p) level. In the crystals, π-π inter-ations and weak C-H⋯O and C-H⋯π inter-actions are observed. The effect of these inter-molecular inter-actions in the solid state can be seen by the difference between the experimental and theoretical optimized geometrical parameters. The structures have also been characterized by UV-Vis spectroscopy. The smallest energy gaps of 2.86 and 2.96 eV enhance the nonlinear responses of such mol-ecular systems. Hirshfeld surface analyses and 2D (two-dimensional) fingerprint plots were used to qu-antify the inter-molecular inter-actions present in the crystal, indicating that these are the most important contribution to the crystal packing.

Design, growth and characterization of D-π-A-π-D based efficient nonlinear optical single crystal for optical device applications

Third order nonlinear material of 4-[(1 E)-3-(5-chlorothiophen-2-yl)-3-oxoprop-1-en-1-yl]phenyl4-methylbenzene-1-sulfonate (4 TP MS) was synthesized by Claisen Schmidt condensation reaction method and single crystals were grown by slow evaporation technique. The functional groups corresponding to the vibrational frequencies has been confirmed through FT-IR and FT-RAMAN spectroscopic techniques. The single crystal XRD analysis revealed the crystal is belonging to monoclinic crystal structure with P21/n space group. The optical properties were studied by UV-VIS spectroscopy and photoluminescence spectroscopy. The cut-off wavelength of 4 TPMS is found to be 432 nm and the crystal is transparent in entire visible and near IR region. Using absorbance data, the parameters like extinction co-efficient, reflectance, electrical conductivity, optical conductivity, complex dielectric constant, lattice dielectric constant and ratio of carrier concentration to effective mass has been analyzed. The crystal has blue light emission property with less defects were observed from photoluminescence studies. The 4 TPMS is thermally stable up to 254 °C. The dielectric properties like dielectric constant and dielectric loss were studied. The low value dielectric loss at high frequency region enhances the optical quality of the material. The third order nonlinear properties of nonlinear absorption and nonlinear refraction were studied through open/closed aperture Z-Scan technique. The high value nonlinear absorption co-efficient of 4 TPMS makes the material suitable for optical limiting application. These optical limiting properties were extracted from open aperture Z-Scan data and this behavior is due to reverse saturable absorption. The large value of third order nonlinear susceptibility is of the order of 10−11 esu and material has better capability to be used optical device applications.

Molecular Structure Investigation On Organic Chalcone Derivative of (E)-3-(4-Bromothiophen-2-1-(3-nitrophenyl)prop-2-en-1-one: A Combined Experimental and Theoretical Study

A new chalcone derivative namely, (E)-3-(4-Bromothiophen-2-1-(3-nitrophenyl)prop-2-en-1-one was successfully synthesized using Claisen-Schmidt condensation reaction method. The compound crystallized in the orthorhombic, Pnma space group. The synthesized molecule was well characterized using spectroscopic techniques of Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (NMR) and Ultraviolet-Visible (UV-Vis) absorption. Molecular and crystal structures were determined by single crystal X-ray diffraction method. The molecular geometry obtained from X-ray structure determination was further optimized by Density Functional Theory (DFT) using B3LYP/6-311++G(d,p) basis set in the ground state to calculate the vibrational wavenumbers and isotropic chemical shifts. TD-DFT/B3LYP method has been employed to calculate the electronic properties and frontier molecular orbital (FMO). The discrepancies between experimental and theoretical values are due to the fact that the molecule is calculated as an isolated molecule in the gaseous phase. The intermolecular interactions in the solid state contribute to the comformational changes of the molecular structure and the subsequently the crystal structure.