The present study epitomizes the design, synthesis, photophysics, solvation, and interaction with calf-thymus DNA of a potential antitumor, anticancer quinoline-appended chalcone derivative, (E)-3-(anthracen-10-yl)-1-(6,8-dibromo-2-methylquinolin-3-yl)prop-2-en-1-one (ADMQ) using steady state absorption and fluorescence spectroscopy, molecular modeling, molecular docking, Fourier-transform infrared spectroscopy (FTIR), molecular dynamics (MD) simulation, and gel electrophoresis studies. ADMQ shows an unusual photophysical behavior in a variety of solvents of different polarity. The dual emission has been observed along with the formation of twisted intramolecular charge transfer (TICT) excited state. The radiationless deactivation of the TICT state is found to be promoted strongly by hydrogen bonding. Quantum mechanical (DFT, TDDFT, and ZINDO-CI) calculations show that the ADMQ is sort of molecular rotor which undergoes intramolecular twist followed by a complete charge transfer in the optimized excited state. FTIR studies reveals that ADMQ undergoes important structural change from its native structure to a β-hydroxy keto form in water at physiological pH. The concentration-dependent DNA cleavage has been identified in agarose gel DNA electrophoresis experiment and has been further supported by MD simulation. ADMQ forms hydrogen bond with the deoxyribose sugar attached with the nucleobase adenine DA-17 (chain A) and result in significant structural changes which potentially cleave DNA double helix. The compound does not exhibit any deleterious effect or toxicity to the E. coli strain in cytotoxicity studies. The consolidated spectroscopic research described herein can provide enormous information to open up new avenues for designing and synthesizing chalcone derivatives with low systematic toxicity for medicinal chemistry research.

We have synthesized a small library of blue‐to‐green emissive single benzene‐based fluorophores (SBFs) in a short synthetic sequence. The molecules exhibit good Stokes shift in the range of 60–110 nm and select examples also possess very high fluorescence quantum yields of up to 87%. Theoretical investigations into the ground state and excited state geometries of many of these compounds reveal that good degree of planarization between the electron donor secondary amines and electron accepting benzodinitrile units can be achieved under certain solvatochromic conditions, giving rise to the strongly fluorescent behavior. On the other hand, the excited state geometry which lacks co‐planarity of the donor amine and the single benzene moiety can open up a non‐fluorescent channel. Additionally, in molecules with a dinitrobenzene acceptor, the perpendicular nitro moieties render the molecules completely non‐emissive.

The usefulness of heterocyclic chalcone derivative as a therapeutic target in controlling hypertension and its site specific binding interaction with model transport protein to get a clear picture about its delivery mechanism. AbstractInhibition of Angiotensin Converting Enzyme (ACE) is identified as a main therapeutic target in controlling hypertension. The principal intent of this work is to investigate the ACE inhibitory property of a quinoline appended chalcone derivative (E)-3-(anthracen-10-yl)-1-(6,8-dibromo-2-methylquinolin-3-yl)prop-2-en-1-one (ADMQ), and its binding mechanism with model transport protein BSA by employing steady state and time resolved fluorescence, Circular Dichroism (CD), in silico Molecular Docking, Induced Fit Docking (IFD) and Molecular Dynamics (MD) simulation. Incubation of ADMQ with kidney cortex plasma membrane shows considerable antihypertensive effect by the inhibition of ACE. ADMQ undergoes strong interaction with ACE both in absence and presence of BSA. Comparable ACE inhibitory mechanistic profile of ADMQ with standard drug captopril has been identified in terms of ligand interaction pattern, changes in secondary structural elements and protein RMSF. The steady state emission of BSA undergoes a remarkable decrement via ground state complex formation upon addition of ADMQ in aqueous buffer solution of BSA at physiological pH 7.4 contrary to the time resolved and FRET measurement where both the static andenergy transfer mechanism co-exists. Rotationally restricted ADMQ molecule shows strong binding affinity towards subdomain IIA of site I with a close proximity (2.45 nm) of the Trp 213 residue. The minor decrease of α-helical content as calculated from CD spectral measurement and 1-3 Å change in protein RMSD during MD simulation clearly indicate that the polypeptide chain is partially destabilized due to the above site specific accommodation of the host (ADMQ). A slight diminution in the ACE inhibitory profile is observed in presence of BSA; however BSA shows lesser binding towards ADMQ in presence of the target enzyme. The spectroscopic research described herein may provide enormous important information for ACE inhibition of chalcone derivative and its detail binding interaction with carrier protein for the chalcone based drug designing in medicinal chemistry research.

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This article reports the first perbromination of β-pyrrole and meso-phenyl groups of the 5,10,15,20-tetrakis(3ʼ,5ʼ-dimethoxyphenyl)porphinato copper(II) to generate highly brominated porphyrin, 2, 3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(2ʼ,6ʼ-dibromo-3ʼ,5ʼ-dimethoxyphenyl)-porphinato copper(II), CuT(3ʼ,5ʼ-DMP)PBr 16 complex. Its crystal structure exhibited unusual five-coordination geometry with saddle shaped conformation of the porphyrin core. H 2 T(3ʼ,5ʼ-DMP)PBr 16 and its metal complexes exhibited large anodic shift of oxidation potentials with marginal changes in reduction potentials relative to their corresponding octabromotetraphenylporphyri n, MTPPBr 8 derivatives. The enhanced electron deficiency of the ZnT(3ʼ,5ʼ-DMP)PBr 16 complex was probed by axial ligation of various Lewis bases with differing pK a values. The ZnT(3ʼ,5ʼ-DMP)PBr 16 complex exhibited decrease in equilibrium constants for the ligation of bases relative to sterically unhindered ZnTPPBr 8 . This has been ascribed to the sterics induced by the bulky ortho-bromo phenyl substituents that prevents the facile binding of Lewis bases to the Zn(II)-center.