Synthesis,characterization, pharmacological,molecular modeling and antimicrobial activity evaluation of novel isomer quinoline derivatives

The structural and spectroscopic characteristics of the synthesized structurally novel compound 4-chloro-6-methylquinoline-2(1H)-one (4C6MQ) and its isomer 4-chloro-8-methylquinoline-2(1H)-one (4C8MQ) have been examined by means of experimental and computational quantum chemical methods like density functional theory (DFT). The crystal structure of the 4C6MQ compound has been brought to light by single-crystal x-ray diffraction (SCXRD) method which consists of two independent molecules (A and B) in the asymmetric unit with similar conformations. Both the isomer compounds are characterized spectroscopically by FTIR, FT-Raman, UV-Vis, and NMR spectrum and compared with DFT results. The geometries of the isomer compounds have been optimized by using DFT/B3LYP method with the 6-311G++(d,p) basis sets. From the optimized geometry of the compounds, geometric parameters (bond lengths, bond angles, and torsion angles); vibrational analysis; chemical shifts; and electronic absorption of the isomer compounds have been computed and compared with the experimental result. The detailed assignments of vibrational wave numbers have been prepared based on potential energy distribution (PED) which was carried out in the VEDA4 program. In addition, natural bonding orbital analysis, frontier molecular orbital, and molecular electrostatic potential have been explained theoretically. The in silico (absorption, distribution, metabolism, excretion and toxicity) studies were analyzed to identify the potential drug likeliness of the isomer compounds. The implications of the inhibitory activity of isomer compounds against DNA gyrase and lanosterol 14 α-demethylase enzyme by molecular docking are discussed. Further, the isomer compounds were screened for their antibacterial and antifungal activities.     

Database diversity assessment: New ideas, concepts, and tools

We present some new ideas for characterizing and comparing largechemical databases. The comparison of the contents of large databases is nottrivial since it implies pairwise comparison of hundreds of thousands ofcompounds. We have developed methods for categorizing compounds into groupsor series based on their ring-system content, using precalculatedstructure-based hashcodes. Two large databases can then be compared bysimply comparing their hashcode tables. Furthermore, the number of distinctring-system combinations can be used as an indicator of database diversity.We also present an indepen- dent technique for diversity assessment calledthe saturation diversity approach. This method is based on picking as manymutually dissimilar compounds as possible from a database or a subsetthereof. We show that both methods yield similar results. Since the twomethods measure very different properties, this probably says more about theproperties of the databases studied than about the methods.     

Cobalt and manganese nets via their wires: facile transformation in metal-diorganophosphates

The manganese and cobalt complexes [M(dtbp)2]n (M=Mn, Co; dtbp=di-tert-butyl phosphate), which exist as one-dimensional molecular wires, transform to [M(dtbp)2(bpy)2.2H2O]n by the addition of 4,4-bipyridine (bpy) at room temperature; the latter compounds form noninterpenetrating rectangular grid structures.     

New substrates in Belousov-Zhabotinsky reaction employing mixed media

Several substrates have been employed in different oscillatory systems. A serious limitation is the low solubility in water. This has been overcome by employing aqueous-organic mixed media in the iodate-system as well as the uncatalyzed and catalyzed [Ce(III) or Ferroin] systems. The present paper deals with the study of fifteen new substrates in the bromate-Mn(II) oscillatory system employing aqueous-organic mixed media.

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Non-interpenetrating transition metal diorganophosphate 2-dimensional rectangular grids from their 1-dimensional wires: structural transformations under mild conditions

The manganese, cobalt, and cadmium complexes [M(dtbp)2]n (M = Mn (1) and Co 2) and [Cd(dtbp)2(H2O)]n (3) (dtbp = di-tert-butyl phosphate), which exist as one-dimensional molecular wires, transform to non-interpenetrating rectangular grids [M(dtbp)2(bpy)2.2H2O]n (M = Mn (4), Co (5), and Cd (6)) by the addition of 4,4-bipyridine (bpy) at room temperature. Products 4-6 have also been prepared by a room-temperature reaction or by solvothermal synthesis in methanol through a direct reaction between the metal acetate, di-tert-butyl phosphate, and 4,4'-bipyridine (bpy) in a 1:2:2 molar ratio. Single-crystal X-ray structure determination of 4-6 shows that these compounds are composed of octahedral transition metal ions woven into a two-dimensional grid structure with the help of bpy spacer ligands. The axial coordination sites at the metal are occupied by bulky unidentate dtbp ligands, which prevent any interpenetration of the individual grids. The change of reaction conditions from solvothermal to hydrothermal, for the attempted synthesis of a magnesium grid structure, however leads to the isolation of an organic phosphate [(H2bpy)(H2PO4)2] (7) and an inorganic phosphate [Mg(HPO4)(OH2)3] (8). Compound 7 can also be prepared quantitatively from a direct reaction between bpy and H3PO4. The new organic phosphate 7 is a unique example of a phosphate material with alternating layers of [H2bpy]2+ cations and [H2PO4]- anions that are held together by hydrogen bonds. Solid-state thermal decomposition of 4-6 produced the respective metaphosphate materials [M(PO3)2] (M = Mn (9), Co (10), and Cd (11)). All new metal-organic phosphates have been characterized by elemental analysis, thermal analysis (TGA, DTA, DSC), and IR and NMR spectroscopy. The metaphosphate ceramic materials were characterized by IR spectral and powder X-ray diffraction studies.     

A Simple Technique for Submicron Scale Patterning of Silver Using Visible Light Interference

A novel, one step and simple methodology for the fabrication of submicron scale silver patterns is demonstrated. The photosensitivity of an organic silver salt has been utilized for this purpose of fabrication. The silver-organometallic compound is converted to metallic silver selectively in the illuminated regions. Surface morphology was studied by scanning electron microscopy (SEM). Energy dispersion spectroscopy (EDS) shows the presence of silver in the developed film. X-ray photoelectron spectroscopy (XPS) confirms the formation of metallic silver. Feature sizes of the order of 200 nm have been achieved using this technique.     

Biocatalytic Synthesis of Two-Photon Active Resveratrol Oligomer

Resveratrol (3,5,4′ trihydroxy trans-stilbene) is a plant based phenolic compound. Enzymatic oligomerization of trans-resveratrol using horseradish peroxidase followed by characterization of the oligomer is presented. The oligomerization reaction was monitored using UV-Visible absorption and fluorescence spectroscopies. The oligomer exhibits strong two-photon-induced fluorescence. Computational modeling using spin-density calculations was performed to investigate the most probable reaction sites and the nature of products formed in the oligomerization process.