Synthesis and Pharmacological Evaluation of 4‐Aryloxyquinazoline Derivatives as Potential Cytotoxic Agents

In the present study, novel 4‐aryloxyquinazoline derivatives were synthesized and screened for in vitro cytotoxicity on human cancer cell lines at 10 μM. Some of the synthesized compounds displayed moderate to significant and selective cytotoxic activity against various leukemia, melanoma, ovarian, breast, and colon cancer cell lines. (E)‐3‐(3,4‐Dimethoxyphenyl)‐1‐(4‐(quinazolin‐4‐yloxy)phenyl)prop‐2‐en‐1‐one ( 9b ) was the most potent compound among all with an average growth inhibition of 70% against leukemia cancer cell lines. The compound also produced strong inhibition (75%) of colon cancer cell lines with 42.58% lethality of HCT‐116 cell line.     

Palladium acetate and phosphine assisted synthesis of five-membered N-heterocycles

A wide variety of biological activities are possessed by oxygen, nitrogen, and sulfur heterocyclic compounds and much research has been performed for the synthesis of these heterocycles. The synthesis of heterocycles with the help of metal became highly rewarding and important method in organic synthesis. This review article concentrated on the synthesis of nitrogen containing five-membered heterocylces in the presence of palladium acetate and phosphine as a catalyst.     

Effect of modifiers field strength on optical,structural and mechanical properties of lanthanum borosilicate glasses

An attempt has been made to understand the role of modifiers on physical, mechanical and spectroscopic properties of AO-SiO₂–B₂O₃-La₂O_3, (A = Mg, Ca, Sr, Ba) glasses. The replacement of alkaline earth metals which act as modifier in glass matrix exhibit, marked difference in their strength and optical properties. The results are discussed in light of non-bridging oxygens (NBO), optical basicity, refractive index, polarisability, hardness and fracture toughness. In addition to this, Weibull statistics and cumulative probability of failure have also been analyzed. Band gap of glasses has been calculated using UV–visible spectroscopy where the variation in band gap is observed to increase with the addition of heavier modifier. Raman features have been explored for all prepared samples through Raman spectra which is in agreement with Fourier transform infra-red (FTIR) spectroscopy and Fourier transform nuclear magnetic resonance (FT-NMR).     

Synthesis of Polylactide: Effect of Dispersion of the Initiator

The ring opening polymerization of L-lactide was studied in bulk using stannous octoate as initiator. In some experiments, triphenylphosphine, a Lewis base was also used as co-initiator. The polymerization was carried out at 130°C up to 29 h. The monomer was used after recrystallizing three times with dry toluene. Experiments were carried out using a wide range of monomer to initiator ratio. The averages and distributions of molar masses of resulting PLA have been determined by means of size exclusion chromatography, SEC. It is shown that the (mode, process) procedure of dispersion of the catalyst in polymerization system affects the molar mass distribution of the product as is evidenced by the bimodality or even trimodality observed in the SEC chromatograms.     

Effect of cation doping on low-temperature specific heat of LaMnO3 manganite

We have investigated the thermodynamic properties of perovskite manganite LaMnO₃, the parent compound of colossal magnetoresistive manganites, with the Ca²⁺ doping at the A-site. As strong electron-phonon interactions are present in these compounds, the lattice part of the specific heat deserves proper attention. We have described the temperature dependence of the lattice contribution to the specific heat at constant volume (C_v(lattice)) of La_1−xCa_xMnO₃ (x=0.125, 0.175, 0.25, 0.35, 0.50, 0.67, 0.75) as a function of temperature (1 K–20 K) by means of a rigid ion model (RIM).The trends of specific heat variations with temperature are almost similar at all the composition. The Debye temperatures obtained from the lattice contributions are found to be in somewhat closer agreement with the experimental data. The specific heat values revealed by using RIM are in closer agreement with the available experimental data, particularly at low temperatures for some concentrations (x) of La_1−xCa_xMnO₃. The theoretical results at higher temperatures can be improved by including the effects of the charge ordering, van der Waals attraction and anharmonicity in the framework of RIM.     

Insights into the photophysics,protonation and Cu2+ ion coordination behaviour of anthracene-9,10-dione-based chemosensors

Carboxylic acid–diamine-based Cu²⁺ chromogenic sensors (3 and 4) exhibited colour switching from red to blue with good sensitivity and selectivity towards Cu²⁺ among other physiologically important alkali, alkaline earth and heavy metal ions. This colour-switching phenomenon arises due to selective deprotonation of aryl amine NH by Cu²⁺. Significantly, chemosensor 3 (λ_max 492 nm) shows multiple modes of complexation towards Cu²⁺. It is very much evident from the appearance of blue colour (λ_max 615 nm) at pH >7.0 and yellow colour (λ_max 465 nm) at pH < 4.0. In addition, chemosensor 3 exhibits a unique logic gate system that involves ‘INHIBIT’ and ‘TRANSFER’ logic gates.     

Sorption of some isomeric monohydric alcohols on egg albumin

Summary Sorption of iso-propyl, iso-butyl, sec-butyl, tert-butyl and iso-amyl alcohols on egg albumin has been studied at 35 °C by using quartz fiber spring technique. Sorption is related inversely to the molar volume of the sorbate. The specific surface area of egg albumin has been calculated by the BET method. The thermodynamic functions have also been evaluated.With 3 figures and 2 tables