Hybrid Class Phenylthiazole and 1,2,3,4‐Tetrahydronaphthalene Target Sertraline Transporter for Antidepressant Action Revealed by Molecular Docking Studies

Phenylthiazolyl‐substituted 1,2,3,4‐tetrahydronaphthalene derivatives were synthesized, and their chemical structures were elucidated by Fourier transform infrared, ¹H‐NMR, ¹³C‐NMR spectral data and elemental analyses. Antidepressant‐like activities of these compounds were screened using both Porsolt's behavioural despair on albino mice and tail suspension tests. Open field test was also performed for the examination of probable neurological deficits, which may interfere with the test results. The test compounds exhibited different levels of antidepressant activities. Additionally, the key ligand was further substantiated by docking experiment to explore plausible mode of binding in molecular dynamics overflow. The studies elucidates role of a hydrophilic H‐bonding region and pi‐cation binding as a major driving force for biological activity.     

Synthesis,structural, DFT investigations and antibacterial activity assessment of pyrazoline-thiocyanatoethanone derivatives as thymidylate kinase inhibitors

Two novel compounds 1-(5-[4-fluorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (FSCN) and 1-(5-[4-chlorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (ClSCN) were synthesized and characterized by SC-XRD, 1H NMR, 13C NMR, FTIR, and UV methods. The X-ray diffraction studies were utilized to prove the 3D crystal structures of FSCN and ClSCN. In both the compounds, the packing is mostly driven by C H⋯N, C H⋯O, and C H⋯π (benzene ring as an acceptor) interactions. In ClSCN, additionally, the π⋯π interaction is observed between the pyrazole ring of one molecule and the benzene ring of the other molecule. The experimental values were compared with the results of DFT/B3LYP/6-311G++(d,p) theoretical computations. The pharmacological screening for FSCN and ClSCN was performed using molinspiration and PreADMET web server. To analyze antibacterial inhibition of the synthesized ligands and Ciprofloxacin (control drug) were interacted with antibacterial protein Thymidylate Kinase (TMK) (PDB ID: 4QGG) with the help of AutoDock Vina tool. The ADMET and docking results of FSCN and ClSCN pointed out the better drug likeness nature and good inhibition behavior with TMK protein. The antibacterial in vitro studies suggested that FSCN compound inhibited well with antibacterial strains than that of ClSCN. The current investigation suggests that with further improvements, our compounds could be preferred as substitute medicine for bacterial diseases.     

Effect of γ-radiation on TL,ESR and evaluation of trapping parameters of K2Ca(SO4)2:X (X = Dy or Eu) phosphors

ABSTRACT

The present phosphor K₂Ca(SO₄)_2, doped by dysprosium and europium, is synthesized by the solid-state diffusion method. The doping concentration varied from 0.1 to 0.5?mol% by weight. A phosphor is studied for X-ray powder diffraction, surface morphology analytical scanning electron microscopy and analyzed by energy-dispersive X-ray spectroscopy. The prepared phosphor K₂Ca(SO₄)_2, doped by Dy and Eu, has been characterized for thermoluminescence (TL) glow curve, showing maximum peak temperatures at 176°C and at 200°C, respectively. TL peak intensity of K₂Ca(SO₄)₂: Dy and Eu was compared with the standard TLD CaSO₄:Dy phosphor. Both phosphors show the dose linearity ranging from 20 to 240?Gy doses of γ-rays of ⁶⁰Co source at room temperature. Negligible fading has been observed when irradiated with γ-rays and stored for 60 days without taking any care from sunlight. The TL materials were used in powder forms. The linearity of ESR response with dose for powder forms of K₂Ca(SO₄)₂: Dy was also studied using the signals at g?=?2:0039 (SO₃^?) and at g?=?2:02282 (SO₄^?). It was observed that the range of linearity of dose response extended between 20 and 240?Gy. Kinetic parameters have been calculated using three different methods: Chen's peak shape method, various heating rate method and initial rise method. To study the heating rate method, the glow curve was recorded for the heating rate as 1°C, 3°C, 5°C, 7°C, 9°C each time. Electron spin resonance (ESR) shows the ionic radical formation during γ-irradiation, which is responsible for TL. The effect of temperature and microwave power on the ESR signal was also studied.     

Synthesis and characterization of some bis(cyclopentadienyl)titanium(IV) complexes with internally functionalized oximes(LH): sol–gel transformations of Cp2TiCl2, Cp2TiClL and Cp2TiL2 to nano‐sized anatase titania

Some bis(cyclopentadienyl)titanium(IV) complexes of the type [Cp₂TiCl_2?n{L}_n] {where, n = 1 or 2; L = ONC(R)Ar; R = H or CH₃ and Ar = C₅H₄N‐2, C₄H₃O‐2 or C₄H₃S‐2} have been synthesized by the metathetical reactions of Cp₂TiCl₂ with the sodium salt of internally functionalized oximes in 1:1 and 1:2 stoichiometry in anhydrous THF. All these red to brown colored solid derivatives have been characterized by elemental analyses, FT‐IR and NMR (¹H and ¹³C{¹H}) spectral studies. The FAB mass spectra of some representative derivatives indicate their monomeric nature. Oximato ligands in all the complexes appear to bind the titanium via N and O in a dihapto ( ‐N, O) manner in the solid state. Thermogravimetric curves of [Cp₂TiCl{ONC(CH₃)C₅H₄N‐2}] and [Cp₂Ti{ONC(CH₃)C₅H₄N‐2}₂] suggest the formation of hybrid materials CpTiO(Cl) and Cp₂TiO, respectively, as the final products at 900 °C under nitrogen atmosphere. Sol–gel transformations of Cp₂TiCl₂, [Cp₂TiCl{ONC(CH₃)C₅H₄N‐2}] and [Cp₂Ti{ONC(CH₃)C₅H₄N‐2}₂] yielded titania a–c, respectively, at low sintering temperature (600 °C). The powder XRD patterns, IR as well as Raman spectra of all these oxides indicate the formation of nano‐sized anatase phase. The SEM images of titania a–c indicate agglomers like surface morphologies. The absorption spectra of a–c exhibit an energy band gap in the range of 3.47–3.71 eV. Copyright © 2011 John Wiley & Sons, Ltd.     

Synthesis of 4-alkyl-, 4-aryl- and 4-arylamino-5-aminoisoquinolin-1-ones and identification of a new PARP-2 selective inhibitor

The considerable interest in substituted isoquinolin-1-ones related to 5-aminoisoquinolin-1-one (5-AIQ) as drugs points to a need for an efficient and straightforward synthesis of the 4,5-disubstituted bicycles. Bromination of 5-nitroisoquinolin-1-one gave 4-bromo-5-nitroisoquinolin-1-one but neither this nor 5-amino-4-bromoisoquinolin-1-one would participate in Pd-catalysed couplings. Protection of the lactam as 1-methoxy- and 1-benzyloxy-4-bromo-5-nitroisoquinolines, however, permitted Stille, Suzuki and Buchwald-Hartwig couplings to take place in high yields, insensitive to electronic demands and severe steric bulk in the arylboronic acids. Lithiation of 4-bromo-1-methoxy-5-nitroisoquinoline and quench with iodomethane gave 1-methoxy-4-methyl-5-nitroisoquinoline in low yield. Demethylation of the 1-methoxy-4-substituted-5-nitroisoquinolines with hydrogen bromide gave 4-substituted-5-nitroisoquinolin-1-ones, whereas hydrogenolytic debenzylation was achieved with simultaneous reduction of the 5-nitro group. 5-Amino-4-(4-trifluoromethylphenyl)isoquinolin-1-one was identified as a new potent and selective inhibitor of poly(ADP-ribose)polymerase-2 (PARP-2).     

Glycolipids that elicit IFN-γ-biased responses from natural killer T cells

Natural killer T (NKT) cells recognize glycolipids presented by CD1d. The first antigen described, α-galactosyl ceramide (αGalCer), is a potential anticancer agent whose activity depends upon IFN-γ secretion. We report two analogs of αGalCer based on a naturally occurring glycosphingolipid, plakoside A. These compounds induce enhanced IFN-γ that correlates with detergent-resistant binding to CD1d and an increased stability of the lipid-CD1d complexes on antigen-presenting cells. Structural analysis on one of the analogs indicates that it is more deeply bound inside the CD1d groove, suggesting tighter lipid-CD1d interactions. To our knowledge, this is the first example in which structural information provides an explanation for the increased lipid-CD1d stability, likely responsible for the Th1 bias. We provide insights into the mechanism of IFN-γ-inducing compounds, and because our compounds activate human NKT cells, they could have therapeutic utility.     

A microfluidic platform for high-sensitivity, real-time drug screening on C. elegans and parasitic nematodes

This paper describes a new microfluidic platform for screening drugs and their dose response on the locomotion behavior of free living nematodes and parasitic nematodes. The system offers a higher sensitivity drug screening chip which employs a combination of existing and newly developed methods. Real-time observation of the entire drug application process (i.e. the innate pre-exposure locomotion, the transient response during drug exposure and the time-resolved, post-exposure behavior) at a single worm resolution is made possible. The chip enables the monitoring of four nematode parameters (number of worms responsive, number of worms leaving the drug well, average worm velocity and time until unresponsiveness). Each parameter generates an inherently different dose response; allowing for a higher resolution when screening for resistance. We expect this worm chip could be used as a robust cross species, cross drug platform. Existing nematode motility and migration assays do not offer this level of sophistication. The device comprises two principal components: behavioral microchannels to study nematode motility and a drug well for administering the dose and observing drug effects as a function of exposure time. The drug screening experiment can be described by three main steps: (i) 'pre-exposure study'- worms are inserted into the behavioral channels and their locomotion is characterized, (ii) 'dose exposure'- worms are guided from the behavioral microchannels into the drug well and held for a predefined time, during which time their transient response to the dose is characterized and (iii) 'post-exposure study'- worms are guided back into the behavioral microchannels where their locomotion (i.e. their time-resolved response to the dose) is characterized and compared to pre-exposure motility. The direction of nematodes' movement is reliably controlled by the application of an electric field within a defined range. Control experiments (e.g. in the absence of any drug) confirm that the applied electric fields do not affect the worms' motility or viability. We demonstrate the workability of the microfluidic platform on free living Caenorhabditis elegans (wild-type N2 and levamisole resistant ZZ15 lev-8) and parasitic Oesophagotomum dentatum (levamisole-sensitive, SENS and levamisole-resistant, LEVR) using levamisole (a well-studied anthelmintic) as the test drug. The proposed scheme of drug screening on a microfluidic device is expected to significantly improve the resolution, sensitivity and data throughput of in vivo testing, while offering new details on the transient and time-resolved exposure effects of new and existing anthelmintics.     

Agrobacterium-Mediated Transformation in Alpinia galanga (Linn.) Willd. for Enhanced Acetoxychavicol Acetate Production

Agrobacterium-mediated transformations ensure elevated amounts of secondary metabolite accumulation with genetic and biosynthetic stability. In the present study, Alpinia galanga rich in bioactive compounds was genetically transformed using different strains of Agrobacterium rhizogenes viz. LBA 9402, A ₄ , 532, 2364 and PRTGus. Even though a higher growth rate was obtained with the LBA 9402 strain, maximum acetoxychavicol acetate accumulation (ACA) was seen in the PRTGus transformant. PRTGus root line has shown 10.1 fold higher ACA content in comparison to the control roots. The lowest ACA production was shown by the A ₄ transformant (4.9 fold). The quantification of ACA in the transformed roots was carried out by using HPLC, which was found to be in the order of PRTGus > LBA 9402 > 2364 > 532 > A ₄ . The fast growth rate of hairy roots, genetic stability and their ability to synthesize more than one metabolite offer a promising system for the production of valuable secondary metabolites.     

High pressure behavior and structural properties of transition metal carbides

A pressure induced structural phase transition from NaCl-type (B₁) to CsCl-type (B₂) structure has been predicted in transition metal carbides, namely TiC, ZrC, NbC, HfC, and TaC by using an interionic potential theory with modified ionic charge (Z_m ), which includes Coulomb screening effect due to d-electron. The phase transition pressure (P_T ) relies on large volume discontinuity in pressure–volume relationship, and identifies the structural phase transition from B₁ phase to B₂ phase. The variation of second-order elastic constants with pressure follows a systematic trend identical to that observed in other compounds of NaCl-type structure. The Born criterion for stability is found to be valid in transition metal carbides.