Chalcone Units Research Articles

(E)-1-(3,4-Di-meth-oxy-phen-yl)-3-(1,3-diphenyl-1H-pyrazol-4-yl)prop-2-en-1-one.

In the title compound, C26H22N2O3, the dihedral angle between the benzene and pyrazole rings of the chalcone unit is 88.3 (1)°. The pyrazole ring has two attached phenyl rings that form dihedral angles with the pyrazole ring of 22.6 (2) and 40.0 (1)°. In the crystal, pairwise C-H⋯O hydrogen bonds generate R 2 2(20) inversion dimers.

Smectogenic asymmetric naphthalene derived chalcones: Self-assembling behaviour and DFT studies

A series of new naphthalene derived asymmetric benzoates incorporating chalcone unit NPCH-(2–16) have been synthesized and investigated for their self-assembling behaviour. The naphthalene end of molecules linked to decyloxy long chain whereas the other end possess systematically substituted chalcone unit connected through ester and imine linking mesogenic units. New molecules have been found to exhibit smectogenic behaviour investigated by POM (polarising optical microscopy) and DSC (differential scaling calorimetry) investigations. Early members (C1 and C7) showed enantiotropic smectic-A (SmA) behaviour, whereas molecules with C8 and C10 showed enantiotropic SmA along with monotropic smectic-C (SmC) also during cooling scans. All afterwards molecules (C12-C16) with longer alkyl chains tend to exhibit enantiotropic SmC mesophase. For one of the representative compounds, the presence of mesophase was confirmed by VT-XRD (variable temperature X-ray-crystallography) analysis. Additionally, the density functional theory (DFT) method has been applied to provide an in-depth analysis of the relationship between the computed structural (length, aspect ratio) and electronic (dipole moment, polarizability) variables and the mesomorphic behaviour of investigated compounds.

Synthesis and crystal structure of (2E)-1-[3,5-bis-(benz-yloxy)phen-yl]-3-(4-eth-oxy-phen-yl)prop-2-en-1-one.

In the title compound, C31H28O4, the phenyl rings of the chalcone unit subtend a dihedral angle of 26.43 (10)°. The phenyl rings of the pendant benz-yloxy groups are orientated at 75.57 (13) and 75.70 (10)° with respect to their attached ring. In the crystal, weak C-H⋯O and C-H⋯π inter-actions link the mol-ecules. The inter-molecular inter-actions were qu-anti-fied and analysed using Hirshfeld surface analysis, which showed a breakdown into H⋯H (49.8%), H⋯C/C⋯H (33.8%) and H⋯O/O⋯H (13.6%) inter-actions with other types making negligible contributions.

Synthesis and Antiproliferative Effect of New Alkyne-Tethered Vindoline Hybrids Containing Pharmacophoric Fragments.

In the frame of our diversity-oriented research on multitarget small molecule anticancer agents, utilizing convergent synthetic sequences terminated by Sonogashira coupling reactions, a preliminary selection of representative alkyne-tethered vindoline hybrids was synthesized. The novel hybrids with additional pharmacophoric fragments of well-documented anticancer agents, including FDA-approved tyrosine-kinase inhibitors (imatinib and erlotinib) or ferrocene or chalcone units, were evaluated for their antiproliferative activity on malignant cell lines MDA-MB-231 (triple negative breast cancer), A2780 (ovarian cancer), HeLa (human cervical cancer), and SH-SY5Y (neuroblastoma) as well as on human embryonal lung fibroblast cell line MRC-5, which served as a reference non-malignant cell line for the assessment of the therapeutic window of the tested hybrids. The biological assays identified a trimethoxyphenyl-containing chalcone-vindoline hybrid (36) as a promising lead compound exhibiting submicromolar activity on A2780 cells with a marked therapeutic window.

New symmetric/unsymmetrical self-assembling salicylaldimine-chalcones: Synthesis, photophysical study and DFT approach

To understand the impact of chalcone unit, lateral hydroxy group and different alkoxy chain length on the overall mesomorphic properties, new symmetric/unsymmetrical salicylaldimine-chalcone mesogens were synthesized with different alkoxy chains on both terminals of the compound. From the study of mesomorphic behaviour of CHRS-(6–18) series it has been observed that compounds with shorter alkyl chain at both the ends showed nematic behaviour which diminished as the number of carbons increases. The middle members of the series with (n = 12, 14, & 16) displayed enantiotropic smectic C mesophase except the compound with (n = 18) chain which was found to be nonmesogenic. The compounds with a fixed dodecyloxy chain on the chalcone end and a variable alkoxy chain length at the Schiff base end 12-CHRS-(6–18), (n = 6, 8, 10, 14, 16, 18) showed an enantiotropic smectic C mesophase. Higher homologue (n = 18) of both the series were found to be nonmesogenic. All the salicylaldiine-chalcones were also studied for their photophysical properties in solid and solution phase. AIE (aggregation-induced emission) was exhibited by all the compounds. While in solution phase emission property diminished for all the compounds except for CHRS-NO2. To support the experimental findings about the mesomorphic behaviour, DFT calculations were used. Additionally, a comparison of dipole moment, polarizability, molecular electrostatic potentials, frontier molecular orbitals, and thermodynamic variables was given.

A three-step pathway from (2-aminophenyl)chalcones to novel styrylquinoline-chalcone hybrids: synthesis and spectroscopic and structural characterization of three examples.

Three new styrylquinoline-chalcone hybrids have been synthesized using a three-step pathway starting with Friedländer cyclocondensation between (2-aminophenyl)chalcones and acetone to give 2-methyl-4-styrylquinolines, followed by selective oxidation to the 2-formyl analogues, and finally Claisen-Schmidt condensation between the formyl intermediates and 1-acetylnaphthalene. All intermediates and the final products have been fully characterized by IR and 1H/13C NMR spectroscopy, and by high-resolution mass spectrometry, and the three products have been characterized by single-crystal X-ray diffraction. The molecular conformations of (E)-3-{4-[(E)-2-phenylethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H21NO, (IVa), and (E)-3-{4-[(E)-2-(4-fluorophenyl)ethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H20FNO, (IVb), are very similar. In each compound, the molecules are linked into a three-dimensional array by hydrogen bonds, of the C-H...O and C-H...N types in (IVa), and of the C-H...O and C-H...π types in (IVb), and by two independent π-π stacking interactions. By contrast, the conformation of the chalcone unit in (E)-3-{4-[(E)-2-(2-chlorophenyl)ethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H20ClNO, (IVc), differs from those in (IVa) and (IVb). There are only weak hydrogen bonds in the structure of (IVc), but a single rather weak π-π stacking interaction links the molecules into chains. Comparisons are made with some related structures.

Two Ratiometric Fluorescent Probes Based on the Hydroxyl Coumarin Chalcone Unit with Large Fluorescent Peak Shift for the Detection of Hydrazine in Living Cells.

Hydrazine is widely used in industrial and agricultural production, but excessive hydrazine possesses a serious threat to human health and environment. Here two new ratiometric fluorescence probes, DDP and DDC, with the hydroxyl coumarin chalcone unit as the sensing site are developed, which can achieve colorimetric and ratiometric recognition for hydrazine with good sensitivity, excellent selectivity, and anti-interference. The calculated fluorescence limits of detections are 0.26 μM (DDC) and 0.14 μM (DDP). The ratiometric fluorescence response to hydrazine is realized through the adjustment of donor and receptor units in coumarin conjugate structure terminals, accompanied by fluorescence peak shift about 200 nm (DDC, 188 nm; DDP, 229 nm). Stronger electropositivity in the carbon-carbon double bond is helpful to the first phase addition reaction between the probe and hydrazine. Higher phenol activity in the hydroxyl coumarin moiety will facilitate the following dihydro-pyrazole cyclization reaction. In addition, both of these probes realized the convenient detection of hydrazine vapor. The probes were also successfully applied to detect hydrazine in actual water samples, different soils, and living cells.

Optical and electrical properties of new NLO active ethynylated chalcone as solution-processed OLEDs material: Experimental and theoretical approaches

This present study investigated the contribution of new hybrid moieties of ethynylated (C≡C) and chalcone (–CO–CHCH-) units as nonlinear optically active and successfully applied to solution-processed OLEDs material. The simulated data from Density Functional Theory (DFT) indicates that 3-(pyren-1-yl)-1-((4-phenylethylyn)phenyl)-2-propen-1-one (MM-1a) reveals good polarizability properties of total first hyperpolarizability βtot at 842.32 × 10−30 esu associated with low HOMO-LUMO gap at 3.04 eV. The structure-property relationship also was highlighted using TD-DFT calculations for frontier molecular orbitals (FMO), molecular electrostatic potential (MEP) maps and global chemical reactivity descriptors (GCRD). The photophysical behaviours of MM-1a presented emission maxima at 520 nm with large Stokes shifts at 95 nm where this emission shows fluoresce characters and intramolecular charge transfer (ICT) state. Remarkably, a response from the open and closed aperture Z-scan analysis reveals that MM-1a displays reverse saturable absorption (RSA) performance and self-defocusing effects under 532 nm continuous wave (CW) laser. Further, solution-processed OLED featuring single-layer of ITO/PEDOT:PSS/MM-1a/Au displayed electroluminescence effect by intense yellow emission obtained under direct current (DC) voltages supply. From the obtained result, the introduction of ethynyl as spacer in chalcone system facilitated intramolecular charge transfer and finely tuned the electronic properties to enhance NLO response and promising emissive layer for OLED applications.

Synthesis, characterization, crystal structure and mesomorphic behavior of thiophene based homologous series

ABSTRACT Through condensation of 4-n-alkoxybenzaldehyde (n = 2 to 8, 10, 12, 14, 16, 18) with (E)-1-(4-aminophenyl)-3-(thiophen-2-yl)prop-2-en-1-one, new homologous series of rod shaped calamite liquid crystals that merge Schiff base, chalcone and thiophene units have been prepared. All synthesized compounds were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopy. The liquid crystalline properties of the synthesized compounds were investigated using a polarizing optical microscope (POM) and differential scanning calorimetry (DSC). The results indicate that n-heptyloxy (A7) to n-tetradecyloxy (A14) derivatives exhibited monotropic nematic phase while the remaining derivatives of homologous series are non mesomorphic. The n-ethoxy derivative (A2) crystallizes under monoclinic, space group P21/c with unit cell dimension a = 19.343(4) Å, b = 5.8353(9) Å, c = 16.574(4) Å, β = 98.78(2) °, V = 1848.8(7) Å3. The dihedral angle between two phenyl rings of imine linkage in compound A2 is 51.64 (2) °.

66‐1: Invited Paper: Liquid‐Crystal Mixture with a Composition Including Highly Reliable Fluorinated Diluter and RM Monomer for PSVA and PI‐less IPS LCDs

We developed a high reliable diluter 3HFFH3 for LC compositions and a reactive mesogen (RM)‐monomer carrying a polarized UV absorption unit, chalcone. As the diluter does not carry a vinyl group, a trade‐off between response property and reliability could be solved, and we succeeded to fabricate the PSVA cell that showed fast response speed and high voltage holding ratio. In addition, we also succeeded to fabricate the PI‐less IPS cell owing to use the RM‐monomer carrying the chalcone unit combined with the diluter 3HFFH3.

(E)-3-{4,6-Dimeth-oxy-2-[(E)-4-meth-oxy-styr-yl]-3-methyl-phen-yl}-1-(2-hy-droxy-5-meth-oxy-phen-yl)prop-2-en-1-one.

In the title compound, C28H28O6, the benzene rings in the resveratrol moiety are connected by a trans C=C double bond, and the hydroxyl group containing a benzene ring and the central benzene ring are linked through a C=(O)-C=C (enone) moiety to form a chalcone unit. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, pairs of C-H⋯O hydrogen bonds generate dimers and additional weak C-H⋯O inter-actions link the dimers into chains propagating along the b-axis direction.

Fabrication of a novel acrylate polymer bearing chalcone and amide groups and investigation of its thermal and isoconversional kinetic analysis

The aim of the article was to examine the thermal degradation, thermal decomposition kinetics and dielectric behavior of novel poly(APHP-Am–Ac). For this purpose, the novel monomer, 4-(3-(4-acetamidophenyl)-3-oxoprop-1-en-1-yl)phenyl acrylate (APHP-Am–Ac), was synthesized from 1-(4-aminophenyl)-3-(4-hydroxyphenyl) prop-2-en-1-one (APHP) and acetic anhydride reaction. The homopolymer P(APHP-Am–Ac) was prepared by free radical polymerization within dimethylformamide at 80 °C. The presence of rigid and bulky chalcone units in polymer side chains significantly improved the solubility of polyamides, giving them an amorphous nature and good thermal stability. The structural characterization of homopolymer was accomplished using FT-IR and NMR techniques. The thermal stability and degradation features of homopolymer have been performed by using TG analysis and FT-IR during partial degradation at different temperatures. The glass transition temperature of homopolymer was determined by DSC analysis. For thermal decomposition kinetics of poly(APHP-Am–Ac), Flynn–Wall–Ozawa and Kissinger methods were applied to thermogravimetric curves and apparent activation energies (Ea) calculated from these two methods. According to FWO, the activation energy (Ea) of the first step and the second step was found as: 157.78 kJ mol−1 and 151.81 kJ mol−1, respectively. For Kissinger’s model, Ea was calculated as 154.3 kJ mol−1 and 142.83 kJ mol−1, respectively. The dielectric and conductivity measurements of homopolymer were investigated by impedance analyzer technique in a range of 10 Hz–20 kHz frequency at different temperatures (from 25 to 120 °C). The results have been plotted as a function of frequency and temperatures. The values increased significantly with temperature.

Novel liquil crystal compositions for PSVA and IPS

In this paper, we present LC compositions having novel reactive mesogen (RM) carrying a chalcone unit and fluorinated diluter 3HFFH3 showed excellent voltage holding ratio (VHR) after photo irradiation for RM polymerization. On the other hand, LC composition having diluter substituted by alkenyl group showed lower VHR compared with our novel LC composition.

Synthesis, characterization and electrochemical studies of metal-free and metallophthalocyanines containing two different chalcone units substituted on peripherally positions

In this paper, novel two different chalcone compounds (E)-3-(5-chloro-2-hydroxyphenyl)-1-o-tolylprop-2-en-1-one (2a) and (E)-3-(5-bromo-2-hydroxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (2b) and their phthalonitrile compounds (3a and 3b) were synthesized in the first step. Then, metal-free (4a and 4b), cobalt (II) (5a and 5b), copper (II) (6a and 6b) and manganese (III) (7a and 7b) phthalocyanines containing chalcone groups at peripheral positions were synthesized. All novel compounds were characterized by general spectroscopic techniques. The electrochemical studies of cobalt (II) (5a and 5b), copper (II) (6a and 6b) and manganese (III) (7a and 7b) phthalocyanine complexes were determined by cyclic voltammetry (CV) and square-wave voltammetry (SWV). Electrochemical studies display that while the CuPc (6a and 6b) shows just Pc ring-based redox processes, the CoPc (5a and 5b), MnClPc (7a and 7b) exhibit both metal-based and ring based redox reaction owing to the metal 3d orbitals lying among the Pc HOMO and LUMO.

Synthesis, Characterisation and Antimicrobial Evaluation of Chalcone Coupled Biscoumarin Copolyesters

A series of three random copolyesters comprising biscoumarin and chalcone units as prime monomers, spaced with aliphatic alkyl chains of varying methylene units and 4,4′-oxydibenzoate, was synthesized and characterised by FTIR, NMR, TGA, DSC and XRD. The antimicrobial activity of the copolyesters was studied using Agar disc diffusion and broth dilution assay. The inhibitory effects of copolyesters were higher for Gram positive than Gram negative bacteria. All the copolyesters exhibited appreciable antimicrobial activity. In particular, copolyester 4c, poly(biscoumarin-4,4′-oxydibenzoate-3-methoxychalcone) exhibited highest inhibition zone range of 19±0.39 mm for Bacillus subtilis, 20±0.51mm for Staphylococcus aureus and 20±0.22 mm for Staphylococcus epidermidis. Bacillus subtilis was more sensitive towards copolyester 4c exhibiting a minimum inhibitory concentration of 39.05 μg/mL. Chalcone coupled biscoumarin copolyester presented good antimicrobial activities comparable with those of standard antimicrobial agents, Chloramphenicol and Amphotericin-B. Thus the incorporation of biscoumarin and chalcone units in the polymer chain exhibit very good antimicrobial activity against gram positive bacterial and fungal strains.

(E)-1-(Benzo[d][1,3]dioxol-5-yl)-3-([2,2'-bi-thio-phen]-5-yl)prop-2-en-1-one: crystal structure, UV-Vis analysis and theoretical studies of a new π-conjugated chalcone.

In the title compound, C18H12O3S2, synthesized by the Claisen-Schmidt condensation method, the essentially planar chalcone unit adopts an s-cis configuration with respect to the carbonyl group within the ethyl-enic bridge. In the crystal, weak C-H⋯π inter-actions connect the mol-ecules into zigzag chains along the b-axis direction. The mol-ecular structure was optimized geometrically using Density Functional Theory (DFT) calculations at the B3LYP/6-311 G++(d,p) basis set level and compared with the experimental values. Mol-ecular orbital calculations providing electron-density plots of HOMO and LUMO mol-ecular orbitals and mol-ecular electrostatic potentials (MEP) were also computed both with the DFT/B3LYP/6-311 G++(d,p) basis set. The experimental energy gap is 3.18 eV, whereas the theoretical HOMO-LUMO energy gap value is 2.73 eV. Hirshfeld surface analysis was used to further investigate the weak inter-actions present.

Photocrosslinking of Sulfonated Poly(arylene ether ketone)s in a Hydrated State to Obtain Proton Exchange Membranes with High Performance

AbstractNovel sulfonated poly(arylene ether ketone)s (SCKs) containing photosensitive chalcone units in the main chain are synthesized by polycondensation of 4,4′‐dihydroxylchalcone, perfluorobiphenyl, and sodium 5,5′‐carbonyl bis(2‐fluorobenzenesulfonate). Photocrosslinking of SCK membranes in a hydrated state is implemented under UV irradiation, and characterization by UV–vis and X‐ray photoelectron spectroscopic techniques. The crosslinked structure formed in hydrated membranes endows crosslinked SCK membranes with desired properties, such as the greatly improved dimensional and chemical stabilities, relative better mechanical properties and thermal stability, without sacrificing proton conductivity of them. Proton conductivity of crosslinked SCK membranes only drops by 2.7–14%, and reaches 215 mS cm−1at 80 °C, which is higher than that of Nafion117 (163 mS cm−1). Atomic force microscopy and small angle X‐ray scattering analysis verify that the photocrosslinked strategy of SCK membranes in a hydrated state could well preserve percolated hydrophilic channels in membranes and give crosslinked SCK membranes high performance desirable for proton exchange membrane.

New peripherally and non-peripherally tetra-substituted metal-free, magnesium(II) and zinc(II) phthalocyanine derivatives fused chalcone units: Design, synthesis, spectroscopic characterization, photochemistry and photophysics

Chalcone containing new peripherally and non-peripherally tetra-substituted metal-free and metallophthalocyanine derivatives were designed and synthesized (Schemes 1 and 2). The structures of chalcone-phthalocyanines were characterized by a combination of common spectroscopic techniques such as LC–MS/MS (for new phthalonitrile derivative 3a), ground state electronic absorption spectra (for all new phthalocyanines), 1H NMR spectroscopy (for all new compounds), 13C NMR spectroscopy (for new phthalonitrile and metal-free phthalocyanine derivatives), Fourier transform infrared (FT–IR with ATR sampling accessory) (for all new compounds) and MALDI–TOF mass spectral data (for all new phthalocyanines and new phthalonitrile derivative 3b) as well as elemental analysis. In addition, the effects of the presence of different kinds of metal ions [magnesium(II) or zinc (II)] in the phthalocyanine core and the effects of the introduction of (3,4-dimethoxyphenyl)-3-oxoprop-1-en-1-yl)phenoxy units at both peripheral and non-peripheral positions of the phthalocyanine skeleton on photophysical and photochemical properties of the new substituted magnesium(II) and zinc(II) phthalocyanines have also been examined in DMF. The obtained results were compared with each other and with unsubstituted magnesium(II) and zinc(II) phthalocyanines. All newly synthesized phthalocyanines are soluble in common organic solvents as well as no type of aggregation was observed in these solvents. Moreover; the chalcone fused magnesium(II) and zinc(II) phthalocyanines also showed excellent fluorescence properties. Specifically, the new non-peripheral zinc(II) and magnesium(II) chalcone-phthalocyanines have the remarkable potential to be used as Type II photosensitizers for the treatment of cancer in PDT owing to their good singlet oxygen and appropriate photodegradation quantum yields. Since chalcones and their derivatives show a broad range of biological and pharmaceutical activities, these products are promising candidates for various applications, particularly as photosensitizers for photodynamic therapy in combination with fluorescence imaging.

Asymmetric Total Synthesis of Dragonbloodins A1 and A2.

The first asymmetric total synthesis of dragonbloodins A1 and A2, a pair of unprecedented chalcone-flavan heterotrimmers, has been achieved through a series of rationally designed or bioinspired transformations. Key elements of the synthesis include a highly efficient heterotrimerization reaction to assemble the two chalcone units and one flavan unit in one pot and a tandem oxidative dearomatization/cyclization/oxygenation reaction to forge the polycyclic core of dragonbloodins A1 and A2. The present synthesis unambiguously confirms the biogenetic relationship and absolute stereochemistry of dragonbloodins A1 and A2.

Synthesis, Photophysical, Electrochemical Properties and Anticancer, Antimicrobial Activity of N -n-Hexyl-N -Phenylanilinochalcone-Capped Dendrimers

Dendrimers with N-n-hexyl-N-phenylanilinochalcone as surface group and triazole as bridging unit were synthesized in good yields. UV-Visible absorption spectrum of N-n-hexyl-N-phenylanilinocalcone dendrimers show two intense absorption bands at 277–297 and 419 nm and the molar extinction coefficient of the dendrimers increases with increase in the dendrimer generation. In emission spectrum, the chalcone dendrimers show a red shift of 10 nm for the first generation dendrimers when compared to the corresponding zeroth generation dendrimers. In cyclic voltammogram, all the dendrimers show quasi-reversible redox peaks. N-n-Hexyl-N-Phenylanilinochalcone dendrimers show better cell viability (≈55%) even at higher concentration against normal liver cell line. The cytotoxicity of the chalcone dendrimers were carried out on A549 lung adenocarcinoma cell lines at various concentrations. The cytotoxicity of the chalcone dendrimers was found to be dose dependent. The higher generation fluorene and benzene core chalcone dendrimers with more number of chalcone units show significant anticancer activity. Interestingly, all the chalcone dendrimers exhibit significant antimicrobial activity against the tested pathogenic microbes.