Stannoxanes and phosphonates: new approaches in organometallic and transition metal assemblies

Phosphonate ligands, [RPO3]2-, are extremely versatile in the assembly of multi-tin and multi-copper architectures. We have used organostannoxane cores for supporting multi-ferrocene and multi-porphyrin peripheries. The copper-metalated multi-porphyrin compound is an excellent reagent for facile cleavage of DNA, even in the absence of a co-oxidant. Reaction oft-BuPO3H2 with Cu(C104)2. 6H2O in the presence of 2-pyridylpyrazole (2-Pypz) leads to the synthesis of a decanuclear copper (II) assembly

Carboxylation of pincer PCP platinum methoxide complexes under formation of metalla carbonates

The ligand 2,6-bis[(diphenylphosphino)methyl]benzene ((PCP)H) was prepared and characterised in an improved manner. With platinum it forms the complex (PCP)PtOTf which reacts with sodium methoxide to give (PCP)PtOMe as the major product together with a small amount of [(PCP)Pt](2)-mu-H. The platinum methoxide reacts with carbon dioxide to give (PCP)PtO(CO)OMe. Also the dinuclear [(PCP)Pt](2)(mu-O(CO)OMe) is formed in this reaction if (PCP)PtOTf is present. The crystal structures for [(PCP)PtOH2]OTf, PCP)PtOMe, [(PCP)Pt](2)-mu-H and [(PCP)Pt](2)(mu-O(CO)OMe) are reported. (c) 2011 Elsevier Ltd. All rights reserved

Synthesis, Molecular Structure, and Chiroptical Properties of Dibenzylidene Derivatives of Bicyclo[3.3.1]nonane and Brexane.

Synthesis of several enantiomerically pure unsaturated bicyclo[3.3.1]nonane and related brexane (tricyclo[4.3.0.0(3,7) ]nonane) derivatives bearing exocyclic benzylidene substituents from readily available (+)-(1S,5S)-bicyclo[3.3.1]nonane-2,6-dione was accomplished. Molecular geometry and chiroptical properties of compounds with enone and styrene chromophores were studied by X-ray diffraction analysis, molecular modeling, and circular dichroism (CD) spectroscopy. Difunctional 3,7-dibenzylidenebicyclo[3.3.1]nonanes, such as and , exhibited intense CD couplets, arising from the exciton coupling between the two unsaturated chromophores. The observed negative sign of the exciton couplets is congruent with the negative twist (negative chirality) defined by the two interacting transition dipoles. The sign of the Cotton effect corresponding to the π→π* transitions in the CD spectra of monoenone and tricyclic brexane acetate was correlated with the intrinsic dissymmetry (helicity) of the styrene chromophore. Chirality 27:728-737, 2015. © 2015 Wiley Periodicals, Inc

Study of anti-inflammatory, anti-diabetic, and analgesic activity of Oscillatoria annae extract in rats and mice

The aqueous extract of the cyanobacterium Oscillatoria annae was investigated for its anti-inflammatory, anti-diabetic,analgesic and cholesterol regulating properties in different experimental standard animal models. The non-steroidal anti-inflammatory drug, indomethacin (10 mg/kg/body weight) was used as standard in the anti-inflammatory, and analgesic studies, while glibenclamide (600 μg/kg/b.wt.) was used as standard drug in the anti-diabetic study. The results reveal that O. annae possesses significant ameliorating effects in the studied animal models, including rats and mice. These effects were comparable to those obtained after treatment with the standard drugs used in this study. The results indicate that the cyanobacterial extract can act as natural remedy and also open a new avenue to identify the active ingredients behind these effects.Keywords: Oscillatoria annae, anti-inflammatory, anti-diabetic, analgesic, cholestero

A distorted cubic tetranuclear copper(II) phosphonate cage with a double-four-ring-type core

The reaction of Cu<SUB>2</SUB>(O<SUB>2</SUB>CMe)<SUB>4</SUB>&#183;2H<SUB>2</SUB>O with tert-butylphosphonic acid and 3,5-di-tert-butylpyrazole in the presence of triethylamine leads to a high-yield synthesis of the tetranuclear compound [Cu<SUB>2</SUB>(3,5-t-Bu<SUB>2</SUB>PzH)<SUB>2</SUB>(t-BuPO<SUB>3</SUB>)<SUB>2</SUB>]<SUB>2</SUB> (1). The latter has a distorted cubic cage structure and its core resembles the D4R (double-four-ring) motif found in zeolites. The phosphonate, [t-BuPO<SUB>3</SUB>]<SUP>2-</SUP>, functions as a dianionic tridentate ligand, while the pyrazole ligands are neutral and are monodentate. The coordination geometry at each copper atom is distorted square planar with a 3O,1N coordination environment. Magnetic measurements on 1 reveal that the &#967;T product continuously decreases to reach a value very close to zero at 1.8 K, indicating dominant antiferromagnetic interactions between Cu(II) ions that leads to an S = 0 ground state. The tetranuclear cage 1 functions as a very effective artificial nuclease in the presence of an external oxidant, magnesium monoperoxyphthalate

Structural and spectroscopic characterization of tetranuclear iron complexes containing a (P2N2Ph)-N-R bridge

A pair of tetranuclear iron complexes consisting of two Fe-2(Cl(2)bdt)(CO)(5) subunits (Cl(2)bdt = 3,6-dicholorobenzene-1,2-dithiolate) bridged by different cyclic 1,5-diaza-3,7-diphosphacyclooctane (P2N2) ligands were prepared and structurally characterized. In the solid state, the P2N2 ligands adopt a boat conformation, which results in rather short distances between the two Fe-2(Cl(2)bdt)(CO)(5) clusters that promotes electronic communication across the diphosphine ligand

Catalytic Three-Component Domino Reaction for the Preparation of Trisubstituted Oxazoles.

Multicomponent reactions are attractive for assembling functionalized heterocyclic compounds. To this end, an efficient gold-catalyzed three-component domino reaction to form oxazoles directly from imines, alkynes, and acid chlorides is presented. The reaction proceeds in a single synthetic step by using a gold(III)-N,N'-ethylenebis(salicylimine) (salen) catalyst to give trisubstituted oxazoles in up to 96 % yield. The substrate scope, a mechanistic study exploring the role of the gold catalyst, and the synthetic applications of the oxazole products are discussed

Host transcriptome-guided drug repurposing for COVID-19 treatment: a meta-analysis based approach

Background Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been declared a pandemic by the World Health Organization, and the identification of effective therapeutic strategy is a need of the hour to combat SARS-CoV-2 infection. In this scenario, the drug repurposing approach is widely used for the rapid identification of potential drugs against SARS-CoV-2, considering viral and host factors. Methods We adopted a host transcriptome-based drug repurposing strategy utilizing the publicly available high throughput gene expression data on SARS-CoV-2 and other respiratory infection viruses. Based on the consistency in expression status of host factors in different cell types and previous evidence reported in the literature, pro-viral factors of SARS-CoV-2 identified and subject to drug repurposing analysis based on DrugBank and Connectivity Map (CMap) using the web tool, CLUE. Results The upregulated pro-viral factors such as TYMP, PTGS2, C1S, CFB, IFI44, XAF1, CXCL2, and CXCL3 were identified in early infection models of SARS-CoV-2. By further analysis of the drug-perturbed expression profiles in the connectivity map, 27 drugs that can reverse the expression of pro-viral factors were identified, and importantly, twelve of them reported to have anti-viral activity. The direct inhibition of the PTGS2 gene product can be considered as another therapeutic strategy for SARS-CoV-2 infection and could suggest six approved PTGS2 inhibitor drugs for the treatment of COVID-19. The computational study could propose candidate repurposable drugs against COVID-19, and further experimental studies are required for validation

4-(2-Bromophenyl)-2-phenylpyrano[3,2-c]chromen-5(4H)-one

In the title compound, C24H15BrO3, the pyranochromenone ring is essentially planar, while the 2-bromophenyl group is almost perpendicular to it [85.58&amp;#8197;(6)&amp;#176;]. In the crystal, inversion dimers linked by pairs of weak C&amp;#8212;H...&amp;#960; bonds occur; there is also a short interatomic contact found between the Br and carbonyl O atoms [3.016&amp;#8197;(1)&amp;#8197;&amp;#197;]