A highly regio- and chemoselective addition of carbon nucleophiles to pyrimidinones. A new route to C4 elaborated Biginelli compounds

Ethyl 6-methyl-pyrimidine-2-one-5-carboxylates react with C-nucleophiles in a diversity oriented synthetic sequence to afford C4 substituted congeners of medicinally potent Biginelli dihydropyrimidinones, in a highly regioselective manner.     

Controlled self-assembly of squaraines to 1D supramolecular architectures with high molar absorptivity

A tailor made squaraine dye upon binding with Ca2+ self-assembles to form a spherical micellar assembly that reorganises to thermodynamically stable 1D cylindrical rods with high molar absorptivity.     

Regenerable Fe-Mn-ZnO/SiO2 sorbents for room temperature removal of H2S from fuel reformates: performance, active sites, Operando studies

Fe- and Mn-promoted H(2)S sorbents Fe(x)-Mn(y)-Zn(1-x-y)O/SiO(2) (x, y = 0, 0.025) for desulfurization of model fuel reformates at room temperature were prepared, tested and characterized. Sulfur uptake capacity at 25 °C significantly exceeds that of both commercial unsupported ZnO sorbents and un-promoted supported ZnO/SiO(2) sorbents. Sulfur capacity and breakthrough characteristics remain satisfactory after multiple (～10) cycles of adsorption/regeneration, with regeneration performed by a simple and robust heating in air. XRD shows that both "calcined" and "spent" sorbents contain nano-dispersed ZnO, and XPS confirms conversion of ZnO to ZnS. "Calcined" sorbent contains Fe(3+) and Mn(3+) that are reduced to Mn(2+) upon reaction with H(2)S, but not with H(2). Operando ESR is used for the first time to study dynamics of reduction of Mn(3+) promoter sites simultaneously with measuring sulfidation dynamics of the Fe(x)-Mn(y)-Zn(1-x-y)O/SiO(2) sorbent. Fe cations are believed to occupy the surface of supported ZnO nanocrystallites, while Mn cations are distributed within ZnO.     

Computational Study of the Interactions between Benzene and Crystalline Ice Ih: Ground and Excited States

Ground‐state geometries of benzene on crystalline ice cluster model surfaces (I_h) are investigated. It is found that the binding energies of benzene‐bound ice complexes are sensitive to the dangling features of the binding sites. We used time‐dependent DFT to study the UV spectroscopy of benzene, ice clusters, and benzene–ice complexes, by employing the M06‐2X functional. It is observed that the size of the ice cluster and the dangling features have minor effects on the UV spectral characteristics. Benzene‐mediated electronic excitations of water towards longer wavelengths (above 170 nm) are noted in benzene‐bound ice clusters, where the cross‐section of photon absorption by water is negligible, in good agreement with recent experimental results (Thrower et al., J. Vac. Sci. Technol. A, 2008, 26 , 919–924). The intensities of peaks associated with water excitations in benzene–ice complexes are found to be higher than in isolated ice clusters. The π→π* electronic transition of benzene in benzene–ice complexes undergoes a small redshift compared with the isolated benzene molecule, and this holds for all benzene‐bound ice complexes.     

Dowex-promoted general synthesis of N,N′-disubstituted-4-aryl-3,4-dihydropyrimidinones using a solvent-free Biginelli condensation protocol

Dowex-50W ion exchange resin-promoted solvent-free heating of an intimate mixture of an aldehyde, an active methylene compound and N,N′-dimethylurea furnished the title compounds in moderate to good yields.     

Synthesis of 2-oxo/thioxooctahydroquinazolin-5-one derivatives and their evaluation as anticancer agents

An environment friendly method for the synthesis of 2-oxo/thioxooctahydroquinazolin-5-one derivatives has been devised using Ceric ammonium nitrate (CAN) as catalyst and polyethylene glycol (PEG) as solvent. The cytotoxic effect of these compounds was studied on U87 human glioma cells, compounds 4c, 4d and 4e are found to exhibit excellent activity at a concentration as low as 0.06 μg/ml.     

Ceric ammonium nitrate (CAN) catalyzed synthesis of N-substituted decahydroacridine-1,8-diones in PEG

Polyethylene glycol (PEG) was found to be an inexpensive non-toxic and effective medium for the one-pot synthesis of N-substituted decahydroacridine-1,8-diones in the presence of ceric ammonium nitrate (CAN) as the catalyst in high yields. Also, the solvent system can be recovered and reused; making this protocol economically and potentially viable.     

Improved machine learning scoring functions for identification of Electrophorus electricus’s acetylcholinesterase inhibitors

Molecular Diversity - Structure-based drug design (SBDD) is an important in silico technique, used for the identification of enzyme inhibitors. Acetylcholinesterase (AChE), obtained from...     

Estimation of betulinic acid from wild fruit extracts of Ziziphus mauritiana and Ziziphus nummularia from different regions of North India by a validated high-performance thin-layer chromatography method

JPC – Journal of Planar Chromatography – Modern TLC - The Ziziphus fruits are recognized as a rich source of biologically active compounds, such as polysaccharides, phenolics,...