Amino Acid-Derived Sensors for Specific Zn2+ Detection Using Hyperpolarized 13C Magnetic Resonance Spectroscopy

Alterations in Zn²⁺ concentration are seen in normal tissues and in disease states, and for this reason imaging of Zn²⁺ is an area of active investigation. Herein, enriched [1-¹³C]cysteine and [1-¹³C₂]iminodiacetic acid were developed as Zn²⁺-specific imaging probes using hyperpolarized ¹³C magnetic resonance spectroscopy. [1-¹³C]cysteine was used to accurately quantify Zn²⁺ in complex biological mixtures. These sensors can be employed to detect Zn²⁺ via imaging mechanisms including changes in ¹³C chemical shift, resonance linewidth, or T₁.     

Magnetohydrodynamic nonlinear thermal convection nanofluid flow over a radiated porous rotating disk with internal heating

Journal of Thermal Analysis and Calorimetry - Nonlinear convective flow and heat transfer characteristics are analyzed between stationary nonporous and porous rotating disks utilizing graphene...     

Weakly I-continuous functions

Summary Weakly I -continuous functions were introduced and studied by A?ikg?z, Noiri and Yüksel [1]. We further extend their study, generalize some of their results and discuss its properties.     

Convenient resolution of (±)-piperidine-2-carboxylic acid ((±)-pipecolic acid) by separation of palladium(II) diastereomers containing orthometallated (S)-(−)-1-[1-(dimethylamino)ethyl]naphthalene

(±)-Piperidine-2-carboxylic acid ((±)-pipecolic acid) has been resolved by the fractional crystallisation of diastereomeric palladium(II) complexes containing orthometallated (S)-(−)-1-[1-dimethylamino)ethyl]naphthalene. The enantiomers of the acid were liberated from the individual configurationally homogeneous diastereomers of the complex in high yield with []_D ± 26.0 (c 1.00, H₂O). The crystal and molecular structures of both diastereomers of the complex have been determined.     

Synthesis of 1-trifluoroacetyl-3-dialkylamino-methyl-5-monosubstituted benzimidazoline-2-thiones using trifluoroacetic acid as an acylating agent

1-Trifluoroacetyl-3-dialkylaminomethyl-5-monosubstituted benzimidazoline-2-thiones have been synthesized from p-substituted anilines which were acetylated with trifluoroacetic acid. The trifluoroacetanilides were nitrated, reduced and cyclised with carbon disulphide in the presence of alcoholic potassium hydroxide and finally treated with formaldehyde and suitable secondary amines to afford the Mannich bases. The compounds were characterised by their analytical and spectral (ir, pmr, ¹⁹F and mass) data. The synthesized compounds have been screened for anti-inflammatory and analgesic activity and found to be active.     

Solvent effects on the absorption and fluorescence spectra of coumarins 6 and 7 molecules: determination of ground and excited state dipole moment

Absorption and fluorescence emission spectra of coumarins 6 and 7 were recorded in solvents with different solvent parameters, viz., dielectric constant epsilon and refractive index n. The fluorescence lifetime of these dyes were measured in butanol at higher values of viscosity over temperature. Experimental ground and excited state dipole moments are determined by means of solvatochromic shift method and also the excited state dipole moments are determined in combination with ground state dipole moments. It was determined that dipole moments of the excited state were higher than those of the ground state in both the molecules.     

Electrohydrocyclization of alkoxy tether substituted mixed enone/enoate and bisenone systems: retention versus elimination

The electrohydrocyclization of tethered enone/enoate or bisenone systems which contain an alkoxyl substituent in the tether was studied. Rather surprisingly, the cyclization of these compounds afforded very different products depending upon the alkoxy substituent. This behavior and its potential applications will be discussed.