NOPR Collection:

Molybdenum compounds bearing pymS (pyrimidine-2-thiolato) and tertiary phosphine ligands

Mon, 01 Jun 2020 00:00:00 GMT

Title: Molybdenum compounds bearing pymS (pyrimidine-2-thiolato) and tertiary phosphine ligands Authors: Roknuzzaman; Khan, Mahadhi H.; Abedin, S. M. Tareque; Kabir, Shariff E. Abstract: In this paper we have reported mono- and dinuclear molybdenum compounds containing doubly bridging pymS (pyrimidine-2-thiolato) and P(Fu)₃{(Fu = (2-furyl)phosphine)} or P(OMe)₃(trimethyl phosphite). One-pot reaction between [Mo(CO)₃(NCMe)₃] and pymSH (pyrimidine-2-thiol) in the presence of P(Fu)₃ in THF at 50 °C gives the previously reported eight coordinate compound [Mo(к²-pymS)₄] (1) in 17% yield and two new compounds [Mo(CO)₄(P(Fu)₃)₂] (2) and [Mo₂(CO)₄(μ-к²-pymS)₂(P(Fu)₃)₂] (3) in 51 and 15% yields, respectively. A similar reaction involving P(OMe)₃furnishes two mononuclear compounds [Mo(CO)₂(κ²-pyS)₂(P(OMe)₃)] (4) and [Mo(CO)₄(P(OMe)₃)₂] (5) in 20 and 35% yields, respectively. Compounds 2 and 4 are characterized by single-crystal X-ray diffraction analysis in addition to IR, ¹H NMR and ³¹P{¹H} NMR spectroscopic methods. Page(s): 741-746

Synthesis of Na+/Ca2+ ions modified TiO2 xerogels through co precipitation method

Mon, 01 Jun 2020 00:00:00 GMT

Title: Synthesis of Na+/Ca2+ ions modified TiO2 xerogels through co precipitation method Authors: Prathyusha, K.R; Sreenivasan, Koliyat Parayil Abstract: We report a facile method for the synthesis of Na⁺/Ca²⁺ ions modified TiO₂xerogels by coprecipitation followed by calcination process. The resultant materials are well characterized by powder X-ray diffraction, Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy and high resolution transmission electron microscopy. Presence of sodium and calcium ions can influence the crystallinity of rutile TiO₂. The photocatalytic performances of bare rutile TiO₂ along with modified materials such as Na-TiO₂, Ca-TiO₂, Na-Ca-TiO₂materials are evaluated by calculating the amount of hydrogen evolved during the photocatalytic decomposition of water under light irradiation.This study will be effective informulating the effect of alkali/alkaline earth metal ions on the photocatalytic activity of rutile TiO₂. Page(s): 747-751

Microwave assisted template synthesis of metal based EGFR, TRK inhibitors, molecular docking and in vitro biological studies

Mon, 01 Jun 2020 00:00:00 GMT

Title: Microwave assisted template synthesis of metal based EGFR, TRK inhibitors, molecular docking and in vitro biological studies Authors: Jain, Preeti; Singh, Vandna; Tripathi, Vishwas Abstract: Metal based biologically active compounds have been synthesized by microwave assisted template condensation method and characterized by spectro-analytical techniques like molar conductance, UV-visible, infrared and mass spectroscopy and thermogravimetric analysis. The metal is arranged in octahedral geometry surrounded by tetradentate ligand framework. The binding affinity of all the metal complexes has been evaluated theoretically by molecular docking studies against epidermal growth factor receptor (EGFR) and tyrosine kinase (TRK) receptor molecules which are further verified by in vitro anticancer activity. Complex [Cr(C₁₆H₁₁N₄O₂)(NO₃)₂]NO₃have showed potent in vitro cytotoxicity (IC₅₀ value 39.5μM) against SCC4 cancer cell line. Antioxidant study has also performed by DPPH assay and significant results are found.[Fe(C₁₆H₁₁N₄O₂)(OAc)₂]OAc and [Cr(C₁₆H₁₁N₄O₂) (OAc)₂]OAc are most effective antioxidants with 78.7% and 76.8% free radical scavenging activity, respectively. Page(s): 752-759

Thermodynamic and kinetic studies on novel Platinum(II) Complex containing bidentate N,N-donor ligands in ethanol-water medium

Mon, 01 Jun 2020 00:00:00 GMT

Title: Thermodynamic and kinetic studies on novel Platinum(II) Complex containing bidentate N,N-donor ligands in ethanol-water medium Authors: Nandi, Debabrata; Karmakar, Parnajyoti; Dey, Anwesha; Sarkar, Roshni (Sain); Ghosh, Alak K. Abstract: Kinetic and mechanistic investigations have been made on the displacement of the two aqua molecules from the complex 1 i.e., [Pt(2,2′-bipyridine)(H₂O)₂]²⁺represented as {Pt(bpy)} (bpy = 2,2′-bipyridine) at pH 4.0. All the substitution reactions have been monitored at 264, 284 & 317 nm, where the spectral difference between the reactant and product is maximum. Two consecutive reaction steps have been observed for the substitution of aqua molecules with some bidentate N,N-donor ligands namely, dimethylglyoxime (L₁H), 1, 2-cyclohexanedionedioxime (L₂H) and α-furildioxime (L₃H) in ethanol-water medium using variable-temperature and stopped-flow spectrophotometry. Among the two steps, the former is ligand dependent and the later is ligand independent, where chelation is observed. All rate and activation parameters are consistent with associative substitution mechanisms. The thermodynamic parameters have been also calculated, which gives a negative DG⁰ value at all temperatures studied, supporting the spontaneous formation of an outer sphere association complex. The products of the reaction have been characterized with the help of IR and ESI-MS spectroscopic analysis. Page(s): 760-767