Crystal structures of the sulfones of 2,3-diphenyl-2,3-di-hydro-4-1,3-benzo-thia-zin-4-one and 2,3-diphenyl-2,3-di-hydro-4-pyrido[3,2-][1,3]thia-zin-4-one.

The title sulfones, 2,3-diphenyl-2,3-di-hydro-4-1,3-benzo-thia-zine-1,1,4-trione, CHNOS, and 2,3-diphenyl-2,3-di-hydro-4-pyrido[3,2-][1,3]thia-zine-1,1,4-trione, CHNOS, crystallize in space group 2/ with two mol-ecules in each of the asymmetric units and have almost identical unit cells and extended structures. In both structures, the thia-zine rings exhibit a screw-boat pucker. The inter-molecular inter-actions observed are C-H⋯O-type hydrogen bonds and parallel partial π-π stacking between the fused aromatic rings (benzo- or pyrido-) of the core of the mol-ecules within each asymmetric unit, and also connecting to mol-ecules with translational periodicity in the -axis direction in what can be described as columns (two per asymmetric unit) of stacked mol-ecules with alternating chirality.

T3P-Promoted Synthesis of a Series of 2-Aryl-3-phenyl-2,3-dihydro-4-pyrido[3,2-][1,3]thiazin-4-ones and Their Activity against the Kinetoplastid Parasite .

A series of fourteen 2-aryl-3-phenyl-2,3-dihydro-4-pyrido[3,2-][1,3]thiazin-4-ones was prepared at room temperature by T3P-mediated cyclization of -phenyl--aryl imines with thionicotinic acid, two difficult substrates. The reactions were operationally simple, did not require specialized equipment or anhydrous solvents, could be performed as either two or three component reactions, and gave moderate-good yields as high as 63%. This provides ready access to -phenyl compounds in this family, which have been generally difficult to prepare.

Alternating magnetic field mediated release of fluorophores from magnetic nanoparticles by hysteretic heating.

This study explores the use of differential heating of magnetic nanoparticles with different sizes and compositions (MFeO (M = Fe, Co)) for heteroplexed temporal controlled release of conjugated fluorophores from the surface of nanoparticles. By exploiting these differences, we were able to control the amount of hysteretic heating occurring with the distinct sets of magnetic nanoparticles using the same applied alternating magnetic field radio frequency (AMF-RF). Using thermally labile retro-Diels-Alder linkers conjugated to the surface of nanoparticles, the fluorescent payload from the different nanoparticles disengaged when sufficient energy was locally generated during hysteretic heating.

Hydrothermal Synthesis and Structure of a Dinuclear Molybdenum(III) Hydroxy Squarate with a Mo-Mo Bond.

The reaction of molybdenum(II) and chromium(II) acetates with squaric acid in degassed and deionized water under hydrothermal conditions at 150 °C is described. The products have been formulated as M(μ-OH)(μ-CO)(HO)·2HO, where M = Cr () and Mo (), based on combustion elemental analysis, infrared spectroscopy, magic angle spinning (MAS) solid-state carbon-13 nuclear magnetic resonance (NMR), and single-crystal X-ray diffraction. The edge-shared bioctahedral structures involve doubly bridging hydroxide ligands and μ-squarate ligands.

Physicochemical interactions with (-)-epigallocatechin-3-gallate drive structural modification of celiac-associated peptide α-gliadin (57-89) at physiological conditions.

(-)-Epigallocatechin-3-gallate (EGCG), a major phenolic constituent of tea, has been shown to have biological activity within inflammatory pathways involved with food allergies and intolerances. Proposed mechanisms for this effect include sequestration and structural modification of immunostimulatory proteins as a result of interactions with EGCG. The present study employs biophysical techniques including dynamic light scattering, circular dichroism and nuclear magnetic resonance to elucidate the likely mechanism(s) by which EGCG interacts with α2-gliadin (57-89) (α2g), an immunodominant peptide in celiac disease pathogenesis.

Comparison of thermally actuated retro-diels-alder release groups for nanoparticle based nucleic acid delivery.

The present study explores alternate pericyclic chemistries for tethering amine-terminal biomolecules onto silver nanoparticles. Employing the versatile tool of the retro-Diels-Alder (rDA) reaction, three thermally-labile cycloadducts are constructed that cleave at variable temperature ranges. While the reaction between furan and maleimide has widely been reported, the current study also evaluates the reverse reaction kinetics between thiophene-maleimide, and pyrrole-maleimide cycloadducts.

Diffusion coefficient distribution from NMR-DOSY experiments using Hopfield neural network.

Diffusion ordered spectroscopy (DOSY) is a powerful two-dimensional NMR method to study molecular translation in various systems. The diffusion coefficients are usually retrieved, at each frequency, from a fit procedure on the experimental data, considering a unique coefficient for each molecule or mixture. However, the fit can be improved if one regards the decaying curve as a multiexponential function and the diffusion coefficient as a distribution.