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61.
62.
Zhongda Pan Sarah M. Pound Naveen R. Rondla Prof. Dr. Christopher J. Douglas 《Angewandte Chemie (International ed. in English)》2014,53(20):5170-5174
A metal‐free, Lewis acid promoted intramolecular aminocyanation of alkenes was developed. B(C6F5)3 activates N‐sulfonyl cyanamides, thus leading to a formal cleavage of the N? CN bonds in conjunction with vicinal addition of sulfonamide and nitrile groups across an alkene. This method enables atom‐economical access to indolines and tetrahydroquinolines in excellent yields, and provides a complementary strategy for regioselective alkene difunctionalizations with sulfonamide and nitrile groups. Labeling experiments with 13C suggest a fully intramolecular cyclization pattern due to the lack of label scrambling in double crossover experiments. Catalysis with Lewis acid is realized and the reaction can be conducted under air. 相似文献
63.
Zhongda Pan Sarah M. Pound Naveen R. Rondla Christopher J. Douglas 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(20):5270-5274
A metal‐free, Lewis acid promoted intramolecular aminocyanation of alkenes was developed. B(C6F5)3 activates N‐sulfonyl cyanamides, thus leading to a formal cleavage of the N CN bonds in conjunction with vicinal addition of sulfonamide and nitrile groups across an alkene. This method enables atom‐economical access to indolines and tetrahydroquinolines in excellent yields, and provides a complementary strategy for regioselective alkene difunctionalizations with sulfonamide and nitrile groups. Labeling experiments with 13C suggest a fully intramolecular cyclization pattern due to the lack of label scrambling in double crossover experiments. Catalysis with Lewis acid is realized and the reaction can be conducted under air. 相似文献
64.
Dinesh R. Garud Amol R. Jadhav Santosh V. Lahore Nilesh M. Kahar Rohini R. Joshi Ramesh A. Joshi Mamoru Koketsu 《Tetrahedron letters》2014
The regioselective iodocyclization reaction of allene–thioureas is described, for the first time, for the synthesis of bicyclic β-lactams. The substitution at the allenyl part heavily influenced the iodocyclization reaction. The iodocyclization reaction of the unsubstituted allene–thioureas afforded six-membered 3-thia-1-dethiacephems whereas, the substituted allene–thiourea afforded seven-membered thiazepines along with five-membered isopenams. 相似文献
65.
C. Saritha Dilip B. Satpute Rohini Badarayani Anil Kumar 《Journal of solution chemistry》2009,38(1):95-114
Suitable equations have been proposed to correlate thermodynamic properties, like mean ion activity coefficients, volumes
and compressibilities, of amino acids in electrolyte solutions. An amino acid–electrolyte–water interaction parameter is extracted
from the regression of the amino acid property values in aqueous electrolyte solution that is then transferred to an expression
to correlate the properties of the electrolyte in mixtures. The single interaction parameter can successfully correlate the
published data on mean ion activity coefficients, apparent molar volumes and compressibilities of amino acids as well as of
electrolytes in their aqueous mixtures. The equations are tested against the large number of experimental data sets available
in the literature. 相似文献
66.
67.
Sudhansu S. Biswal Debajyoti Choudhury Rohini M. Godbole Ritesh K. Singh 《Pramana》2007,69(5):777-782
We examine, in a model independent way, the sensitivity of a linear collider to the couplings of a light Higgs boson to a
pair of gauge bosons, including the possibility of CP violation. We construct several observables that probe the various possible
anomalous couplings. For an intermediate mass Higgs, a collider operating at a center of mass energy of 500 GeV and with an
integrated luminosity of 500 fb−1 is shown to be able to constrain the ZZH vertex at the few per cent level, with even higher sensitivity for some of the couplings. However, lack of sufficient number
of observables as well as contamination from the ZZH vertex limits the precision to which anomalous part of the WWH coupling can be probed.
相似文献
68.
Gandhaveeti Rohini Konakanchi Ramaiah Anandaram Sreekanth 《Tetrahedron letters》2018,59(43):3858-3862
A green emissive PET operating fluorescent turn-on cell permeable novel probe R1 has been successfully developed and utilized for the detection of Fe+3 in the pure aqueous system at sub-nanomolar level. Moreover, probe R1 demonstrate highly sensitive and selective towards Fe+3 over the other divalent and trivalent metal ions and was established by using fluorescence spectroscopy. The efficiency and aid of R1 was demonstrated by the fluorescence imaging of captured Fe+3 within Pollen grains by using fluorescence microscopy. These results indicate that, this is the first fluorescent turn-on PET probe to detect sub-nanomolar Fe+3 in the pure aqueous system and in cellular level. 相似文献
69.
Alcohols are among the most widely occurring functional groups found in naturally abundant, biologically relevant organic compounds, which in many cases are considered feedstock chemicals. Herein, we report a metal-free method for the deoxygenative coupling of alcohol-derived benzoates and pyridines promoted by visible light. Given the practical, mild and water-compatible conditions, small molecules and DNA headpieces can be successfully functionalized with a range of primary, secondary and tertiary alcohols. This protocol is distinguished by its wide substrate scope and broad applicability, even in the context of late-stage functionalization and DNA–drug coupling reactions.A visible-light-mediated metal-free method for the deoxygenative coupling of alcohol-derived benzoates and pyridines. Given the mild and water-compatible conditions, small molecules and DNA headpieces are functionalized with a wide range of alcohols. 相似文献
70.
Sreekanth Tellamekala Mohan Gundluru Murali Sudileti Santhisudha Sarva Chenna Rohini Kumar Putta Suresh Reddy Cirandur 《Monatshefte für Chemie / Chemical Monthly》2020,151(2):251-260
A straightforward and greener approach has been developed for the synthesis of novel aminomethylene bisphosphonates by one-pot reaction of diverse aryl/heteroaryl amines with dialkyl phosphite and triethyl orthoformate using CuO nanoparticles as catalyst under microwave irradiation and solvent-free conditions. This is an ecofriendly synthetic approach for swift access to a library of diverse aminomethylene bisphosphonates. All the synthesized new compounds were evaluated for their antimicrobial activity by disc diffusion method and antioxidant activity by DPPH, H2O2, and NO methods. The title compounds exhibited significant antioxidant and considerable antimicrobial activities. 相似文献