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101.
An economical approach for the diastereoselective synthesis of highly functionalized carbocyclic spiropyrazolone derivatives having one quaternary and two tertiary stereocenters along with one exocyclic double bond exploiting dual organo-silver sequential catalysis has been developed. The unified method to both cyclohexyl and cyclopentyl spirocompounds involves the reaction of γ- and β-nitroalkynes with alkylidene pyrazolones catalyzed by Hünig’s base followed by carbophilic activation of the triple bond with a Ag(I) salt leading to cyclization via hydroalkylation. 相似文献
102.
Amrita Sikder Debes Ray Vinod K. Aswal Suhrit Ghosh 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(6):1620-1625
Herein we describe the H‐bonding‐regulated nanostructure, thermodynamics, and multivalent binding of two bolaamphiphiles NDI‐1 and NDI‐2 consisting of a hydrophobic naphthalene diimide connected to a hydrophilic wedge by a H‐bonding group and a glucose moiety on its two arms. NDI‐1 and NDI‐2 differ by the single H‐bonding group, namely, hydrazide or amide, which triggers the formation of vesicles and cylindrical micelles, respectively. Although the extended H‐bonding ensures stacking with head‐to‐head orientation and the formation of an array of the appended glucose moieties in both systems, the adaptive cylindrical structure exhibited superior multivalent binding with concanavalin A (ConA) to that of the vesicle. A control amphiphile lacking a H‐bonding group assembled with a random lateral orientation to produce spherical micelles without any notable multivalent binding. 相似文献
103.
Sweety Vashistha Vinod Kumar Kumar Anuj Singh Randhir 《Russian Journal of Electrochemistry》2019,55(3):161-167
Russian Journal of Electrochemistry - Me6-dibenzotetraaza[14] annulene type macrocyclic complexes of Ni(II) and Cu(II) have been synthesized by template method and characterized by employing... 相似文献
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S.K. Srivastava S.K. Sharma K. Vinod V.S. Malik 《Journal of Physics and Chemistry of Solids》2008,69(4):1029-1032
In the present communication we have modified the earlier calculations for the compression dependence of entropy of MgO using recent experimental data and more accurate equation of state. We have estimated the thermal expansivity with the help of the Anderson–Isaak equation at different compressions and selected temperatures up to the melting temperature of the solid. P–V relationship and compression dependence of isothermal bulk modulus are computed with the help of the Stacey equation of state. The results have been compared with those recommended by Cynn et al. [J. Phys. Chem. 99/19 (1995) 7813]. It is found that the entropy decreases with increasing compression along an isotherm. 相似文献
106.
Cobalt ferrite (CoFe2O4) nano-particles have been synthesized successfully and we studied the effect of temperature on them. The particles have been annealed at different temperatures ranging from 373 to 1173 K. Significant effect on the physical parameters like crystalline phase, crystallite size, particle size, lattice strain and magnetic properties of the nano-particles has been investigated. The studies have been carried out using a powder X-ray diffractometer (XRD), a transmission electron microscope (TEM) and a vibrating sample magnetometer (VSM). A thorough study of the variation of specific surface area and particle size with annealing is presented here, with their effects on saturation magnetization. 相似文献
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Daniel Ruth Tripathi Dhananjay Singh Sukhvir Sharma Navneet Yuvraaj Arihant Katyal Deeksha Kumar Vinod 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(7):2805-2815
Journal of Radioanalytical and Nuclear Chemistry - Uranium contamination in the aquatic environment is an emerging concern worldwide. With the development of the global economy, uranium... 相似文献
109.
Metabolism of methylstenbolone studied with human liver microsomes and the uPA+/+‐SCID chimeric mouse model
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Lore Geldof Leen Lootens Michael Polet Daniel Eichner Thane Campbell Vinod Nair Francesco Botrè Philip Meuleman Geert Leroux‐Roels Koen Deventer Peter Van Eenoo 《Biomedical chromatography : BMC》2014,28(7):974-985
Anti‐doping laboratories need to be aware of evolutions on the steroid market and elucidate steroid metabolism to identify markers of misuse. Owing to ethical considerations, in vivo and in vitro models are preferred to human excretion for nonpharmaceutical grade substances. In this study the chimeric mouse model and human liver microsomes (HLM) were used to elucidate the phase I metabolism of a new steroid product containing, according to the label, methylstenbolone. Analysis revealed the presence of both methylstenbolone and methasterone, a structurally closely related steroid. Via HPLC fraction collection, methylstenbolone was isolated and studied with both models. Using HLM, 10 mono‐hydroxylated derivatives (U1–U10) and a still unidentified derivative of methylstenbolone (U13) were detected. In chimeric mouse urine only di‐hydroxylated metabolites (U11–U12) were identified. Although closely related, neither methasterone nor its metabolites were detected after administration of isolated methylstenbolone. Administration of the steroid product resulted mainly in the detection of methasterone metabolites, which were similar to those already described in the literature. Methylstenbolone metabolites previously described were not detected. A GC‐MS/MS multiple reaction monitoring method was developed to detect methylstenbolone misuse. In one out of three samples, previously tested positive for methasterone, methylstenbolone and U13 were additionally detected, indicating the applicability of the method. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
110.