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41.
Arindam Maity Debanjana ChakrabortyAbhijit Hazra Yogesh P. BharitkarSandip Kundu Prakas R. MaulikNirup B. Mondal 《Tetrahedron letters》2014
An inexpensive one-pot green methodology has been developed for the synthesis of thiazolo[2,3-a]isoquinolin-4-ium derivatives by the reaction of different derivatives of isoquinoline and 2-bromoacetophenone/bromoacetonitrile with benzoyl isothiocyanate in aqueous micellar medium. 相似文献
42.
Kakali De Asoke Behera Indranil Banerjee Bharat Sarkar Santanu Ganguly Mridula Misra 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(3):847-861
The aim of this study was to synthesis, a radiolabeled (99mTc) new somatostatin-analogue 6-hydrazinopyridine-3-carboxylic-acid (HYNIC)-Asn3-octreotate (99mTc-HYNIC-AATE), and to evaluate as a candidate for imaging somatostatin-receptor (SSTR)-positive tumors and also compare it with 99mTc-HYNIC-Tyr3-octreotide (99mTc-HYNIC-TOC). Synthesis was performed by Fmoc-solid-phase strategy and 99mTc labeled by SnCl2. Biodistribution and imaging properties of new radiopeptide were also studied in C6 tumor bearing rat. Radiolabeling was performed at high specific activities and it showed high binding-affinity for SSTR2. In biodistribution, radiopeptides have showed high and receptor-specific uptake in the SSTR2 positive organs, tumor with rapid renal excretion from non-target tissues. These results demonstrated that 99mTc-HYNIC-AATE is a new specific radioligand for scintigraphy of somatostatin-receptor-positive tumors. 相似文献
43.
Linear {NiII–LnIII–NiII} Complexes Containing Twisted Planar Ni(μ‐phenolate)2Ln Fragments: Synthesis,Structure, and Magnetothermal Properties 下载免费PDF全文
Sourav Das Atanu Dey Subrata Kundu Sourav Biswas Prof. Dr. A. J. Mota Prof. Dr. Enrique Colacio Prof. Dr. Vadapalli Chandrasekhar 《化学:亚洲杂志》2014,9(7):1876-1887
Sequential reaction of a multisite LH4 ligand {2‐[2‐hydroxy‐3‐(hydroxymethyl)‐5‐methylbenzylideneamino]‐2‐methylpropane‐1,3‐diol} with appropriate lanthanide salts followed by the addition of Ni(NO3)2 ? 6 H2O in a 4:1:2 stoichiometric ratio in the presence of triethylamine afforded four heterobimetallic trinuclear complexes [Ni2Gd(LH3)4] ? 3 NO3 ? 3 MeOH ? H2O ? CH3CN ( 1 ), [Ni2Tb(LH3)4] ? 3 NO3 ? 3 MeOH ? CH3CN ( 2 ), [Ni2Dy(LH3)4] ? 3 NO3 ? 3 MeOH ? H2O ? CH3CN ( 3 ), and [Ni2Ho(LH3)4] ? 3 NO3 ? 3 MeOH ? H2O ? CH3CN ( 4 ). Complexes 1 – 4 possess linear trimetallic cores with a central lanthanide ion. Magnetic studies revealed a predominant ferromagnetic interaction between the Ni and Ln centers. Alternating current susceptibility measurements of complex 3 showed a small frequency dependence of the out‐of‐phase signal, χ′′M , under zero direct current field, but without achieving a net maximum above 2 K. Magnetic studies on 1 revealed that it has a significant magnetocaloric effect. 相似文献
44.
45.
Santanu Panja 《印度化学会志》2022,99(3):100359
Supramolecular gels formed by the self-assembly of organic molecules are useful in many areas from materials to medicine. Of the different applications, exploitation of gels for the visual detection of analytes is a fairly recent trend in gel chemistry. Most of the gel-based sensors rely on non-covalent interactions between the gelator molecules and the added chemical analytes and therefore, often suffer from less selectivity and long response time. In this context, dosimetric gelator probes are superior to other gel-based sensors with high selectivity and fast response time. Unlike non-covalent binding sites, dosimetric gelators typically contain a reaction centre and undergo a specific chemical reaction selective to an analyte resulting in either formation or rupturing of covalent bonds. In this review, we provide an up-to-date report of various reaction-based gel systems applied for the sensing of analytes. We elaborately discuss the concept, design principles, self-assembly properties, and reaction mechanisms of such gelators. We also highlight the limitations, challenges, and the necessity of further exploration of dosimetric gels in this domain. 相似文献
46.
Bhaskar Bishayee Biswajit Ruj Santanu Nandi Rishya Prava Chatterjee Aparajita Mallick Prasenjit Chakraborty Jayato Nayak Sankha Chakrabortty 《印度化学会志》2022,99(1):100302
The current investigation involves a continuous adsorption experiment in a packed bed column for the sorptive elucidation of fluoride from contaminated groundwater using an activated soil-clay mixture. Through the combination of naturally accessible laterite soil with silica enriched clay (3:1 ratio), a low-cost Al–Si heterogeneous material has been developed. Following detailed characterization, the developed materials were employed in a long-time column process to achieve a high degree of fluoride separation from real-world groundwater. In a packed bed column investigation, the effect of bed height, initial fluoride concentration, and flow rate on the breakthrough properties of the adsorption system were investigated. By using a non-linear regression equation, three model kinetics, such as the Thomas Model, Adams-Bohart Model, and Yoon-Nelson Model, were fitted to validate the column-based experimental data, by analysing the breakthrough curves profiles, and distinct kinetic parameters. The Bed Depth Service Time Analysis (BDST) model was tested to express the effect of bed height on breakthrough curves, as well as to predict the time for breakthrough, and material depletion under optimal conditions. The Thomas and Yoon-Nelson models were identified to be the most appropriate ones for describing the entire breakthrough curve, whereas the Adams-Bohart model was only utilised to predict the first half of the dynamic process. With correlation coefficients (R2) 0.96, the experimental results were well suited to Thomas, Yoon-Nelson, and Adams-Bohart models. Finally, regeneration assessment was carried out where even after four cycles of operation, regenerated adsorbent showed a rejection efficacy of 78% to fluoride that proves the viability of the material and methodology. 相似文献
47.
Banerjee Sangeeta Kundu Atreyee Dhak Prasanta 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2409-2435
Journal of Radioanalytical and Nuclear Chemistry - Several treatments for the removal of toxic heavy metals like uranium from wastewater have been developed, but none of them are sufficiently... 相似文献
48.
Kundu Sumana Kraytsberg Alexander Ein-Eli Yair 《Journal of Solid State Electrochemistry》2022,26(9):1809-1838
Journal of Solid State Electrochemistry - Many elements in the periodic table form ionic compounds; the crystal lattices of such compounds contain cations and anions, which are arranged in the way... 相似文献
49.
Conformational Control of Oligo(p‐phenyleneethynylene)s with Intrinsic Substituent Electronic Effects: Origin of the Twist in Pentiptycene‐Containing Systems 下载免费PDF全文
Che‐Jen Lin Dr. Sandip Kumar Kundu Dr. Cheng‐Kai Lin Prof. Jye‐Shane Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14826-14833
Dependence of the backbone planarity of oligo(p‐phenyleneethynylene)s (OPEs) on the intrinsic electronic character of substituents and on the nature of the solvent has been experimentally demonstrated with a series of center‐symmetrical five‐ring systems, pentiptycene‐pentiptycene‐arene‐pentiptycene‐pentiptycene, differing in the substituents on the central arene. In frozen 2‐methyltetrahydrofuran (MTHF), the adjacent pentiptycene units prefer to be in a mutually twisted orientation when the substituents are electron‐withdrawing (F and amido), resulting in a TPPT or TTTT conformation, whereas a planarized PPPP backbone is favored in the case of electron‐donating substituents (alkyl and alkoxy). The propensity to adopt the PPPP form is generally enhanced by replacing MTHF with either methylcyclohexane or mixed ethanol/methanol as solvent. These observations reveal that the twist between adjacent pentiptycene units in OPEs is a consequence of the electronic rather than steric effects of iptycenyl substituents. The electronic effect of iptycenyl substituents is manifested in decreased phenylene π polarizability as the net effect of both electron‐donating hyperconjugation and an electron‐withdrawing inductive effect. Variable‐temperature electronic absorption and emission spectroscopies are the critical tools for this work. Our findings provide important guidelines for conformational and electronic engineering of OPEs and for the design of novel iptycene‐based organic electronic materials. 相似文献
50.
Amongst various carbon sources, xylan was found to be the sole inducer of endoxylanase production by Penicillium janthinellum MTCC 10889 in submerged cultivation. Endoxylanase synthesis by a xylan induced culture was initially repressed after a simultaneous addition of xylose, probably by the inducer exclusion mechanism, but it was resumed and achieved its highest level at a much later stage of growth (at 120 h). Xylose added after 30 h of growth cannot exert its full repressive effect. Although glucose was proved to be a more potent repressor than xylose, supplementation of salicin, an alcoholic β-glycoside containing d-glucose, with pure xylan resulted in an about 3.22 fold increase in the enzyme synthesis at 72 h followed by constant high production of the enzyme at least until the 144th h of growth. Inducing capacity of salicin in a xylan induced culture was significantly reduced when it was added after 30 h of growth. Addition of salicin and xylan help to partially overcome the repressive effect of xylose and glucose. Failure of salicin in recovering the endoxylanase synthesis in actinomycin D and cyclohexamide inhibited the xylan induced culture indicating that salicin cannot initiate the de novo synthesis of the enzyme. 相似文献