Synthesis, XRD and HS-Analysis

An efficient microwave-assisted one-step synthetic route toward Mannich bases is developed from 4-hydroxyacetophenone and different secondary amines in quantitative yields, via a regioselective substitution reaction. The reaction takes a short time and is non-catalyzed and reproducible on a gram scale. The environmentally benign methodology provides a novel alternative, to the conventional methodologies, for the synthesis of mono- and disubstituted Mannich bases of 4-hydroxyacetophenone. All compounds were well-characterized by FT-IR, 1H NMR, 13C NMR, and mass spectrometry. The structures of 1-{4-hydroxy-3-[(morpholin-4-yl)methyl]phenyl}ethan-1-one (2a) and 1-{4-hydroxy-3-[(pyrrolidin-1-yl)methyl]phenyl}ethan-1-one (3a) were determined by single crystal X-ray crystallography. Compound 2a and 3a crystallize in monoclinic, P21/n, and orthorhombic, Pbca, respectively. The most characteristic features of the molecular structure of 2a is that the morpholine fragment adopts a chair conformation with strong intramolecular hydrogen bonding. Compound 3a exhibits intermolecular hydrogen bonding, too. Furthermore, the computed Hirshfeld surface analysis confirms H-bonds and π–π stack interactions obtained by XRD packing analyses

Synthesis, molecular docking and biochemical analysis of aminoalkylated naphthalene-based chalcones as acetylcholinesterase inhibitors

Twelve novel chalcones were synthesized using 2-alkyloxy-naphthaldehydes and Mannich bases of 4-hydroxyacetophenone. The chalcones were characterized using FTIR, 1D and 2D NMR and HRMS spectroscopy. Comparative docking analysis was carried out to screen their affinity towards the AChE enzyme (PDB 1EVE). All chalcones showed lower binding energy (-13.06 to -10.43 kcal/mol) against AChE better than donepezil (-10.52 kcal/mol). All chalcones were potent inhibitors towards AChE, with IC50 values ranging between 0.11 and 5.34 nM better than donepezil (IC50 33.4 nM) and selectivity indexes (0.66–23.83), despite the fact that chalcones 10 and 13 were inactive. The structure activity relationship indicated that introducing diethyl amine in ring A of the chalcone skeleton and the propargyl moiety at ring B was a?rmed to be a prospective drug against AChE. The multifunctional properties of chalcone 15 were all advantages that demonstrate an excellent candidate for the development of an effective drug against AChE

2-Benzyloxynaphthalene aminoalkylated chalcone designed as acetylcholinesterase inhibitor: Structural characterisation, in vitro biological activity and molecular docking studies

The design of an acetylcholinesterase inhibitor with multifunctional properties became the perspective for the development of an effective drug against Alzheimer's disease. Towards this target, 1-{4-hydroxy-3-[(piperidin-1-yl)methyl]phenyl}ethan-1-one (chalcone 3) was prepared and studied as an acetylcholinesterase inhibitor. The novel chalcone 3 was synthesised via Claisen-Schmidt condensation reaction with 84% yield and characterized using 1D and 2D NMR spectroscopy. The in vitro bioactivity studies of chalcone 3 demonstrated excellent inhibitory activity against AChE (IC50 1.0 nM) showing 33-fold better inhibition than donepezil, biometal chelating ability and moderate antioxidant activity. Chalcone 3 with these fascinating multifunctional proprieties can be a good candidate for the development of AD treatments. A molecular modelling investigation revealed that chalcone 3 showed dual binding inhibition of AChE enzyme. XRD shows short intra- and inter-molecular interactions with two chalcone 3 molecules per cell. Interesting Hirshfeld Surface Analysis (HSA) was conducted showing explicit agreement with the XRD analysis

Novel Hexadeca-Substituted Metal Free and Zinc(II) Phthalocyanines; Design, Synthesis and Photophysicochemical Properties

The syntheses of a novel 1,4,8,11,15,18,22,25-octahexyloxy-2,3,9,10,16,17,23,24-octa-(4-trifluoromethoxyphenyl) phthalocyanine (3a) and its zinc(II) phthalocyanine derivative (3b) have been described and characterized by elemental analysis,1H NMR, 13C NMR, 19F NMR, mass, UV-Vis and FT-IR. The newly prepared metal-free phthalocyanine and its zinc(II) counterpart are soluble in most organic solvents. The photophysical and photochemical properties such as aggregation, fluorescence, singlet oxygen generation and photodegradation under light irradiation of these phthalocyanines have been investigated in DMF. The hexadeca-substituted phthalocyanines (3a and 3b) showed longer absorption and emission wavelength values when compared to that of reported phthalocyanine derivatives due to substitution of the all possible positions in the phthalocyanine framework. The zinc(II) phthalocyanine derivative does not only have a good singlet oxygen generation but also has other photophysicochemical properties that enables this phthalocyanine to be useful as a photosensitizer for cancer treatment using photodynamic therapy

Crystal structure of 2-(prop-2-yn-1-yloxy)-1-naphthaldehyde, C14H10O2

C14H10O2, triclinic, P1 (no. 2), a = 7.498(3) Å, b = 7.973(3) Å, c = 9.660(4) Å, α = 67.211(13)°, β = 84.489(14)°, γ= 72.224(14)°, V = 506.8(4) Å3, Z = 2, Rgt(F) = 0.0394, wRref(F2) = 0.1135, T = 100(2) K

Microwave-Assisted Synthesis of Mono- and Disubstituted 4-Hydroxyacetophenone Derivatives via Mannich Reaction: Synthesis, XRD and HS-Analysis

An efficient microwave-assisted one-step synthetic route toward Mannich bases is developed from 4-hydroxyacetophenone and different secondary amines in quantitative yields, via a regioselective substitution reaction. The reaction takes a short time and is non-catalyzed and reproducible on a gram scale. The environmentally benign methodology provides a novel alternative, to the conventional methodologies, for the synthesis of mono- and disubstituted Mannich bases of 4-hydroxyacetophenone. All compounds were well-characterized by FT-IR, 1H NMR, 13C NMR, and mass spectrometry. The structures of 1-{4-hydroxy-3-[(morpholin-4-yl)methyl]phenyl}ethan-1-one (2a) and 1-{4-hydroxy-3-[(pyrrolidin-1-yl)methyl]phenyl}ethan-1-one (3a) were determined by single crystal X-ray crystallography. Compound 2a and 3a crystallize in monoclinic, P21/n, and orthorhombic, Pbca, respectively. The most characteristic features of the molecular structure of 2a is that the morpholine fragment adopts a chair conformation with strong intramolecular hydrogen bonding. Compound 3a exhibits intermolecular hydrogen bonding, too. Furthermore, the computed Hirshfeld surface analysis confirms H-bonds and π⁻π stack interactions obtained by XRD packing analyses