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91.
Tatiana N. Drebushchak Nikita V. Chukanov Elena V. Boldyreva 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(6):o355-o357
The structure of a new polymorph of the title compound, C10H13ClN2O3S, known as the antidiabetic drug chlorpropamide, is monoclinic, in contrast with the two previously described orthorhombic α‐ and β‐forms. The molecules in the γ‐polymorph are linked into bands by hydrogen bonds similar to those in the α‐polymorph. The conformation of the molecules in the γ‐form is close to that in the β‐polymorph. 相似文献
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Let F be a field of characteristic different from 2 and let ø be an anisotropic 8-dimensional quadratic form over F with trivial deter-minant. We study the remaining open cases in the problem of describing the quadratic forms ψ such that ø becomes isotropic over the function field (ψ). 相似文献
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Oleg V. Bityukov Vera A. Vil George K. Sazonov Andrey S. Kirillov Nikita V. Lukashin Gennady I. Nikishin Alexander O. Terentev 《Tetrahedron letters》2019,60(13):920-924
It was discovered that the Kharasch peroxidation of barbituric acids proceeds both with a Cu-catalyst and without a metal catalyst. Despite the presence of possible thermal-initiated side oxidation pathways, α-tert-butylperoxybarbiturates were selectively prepared from substituted barbituric acids and tert-butyl hydroperoxide. 相似文献
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Dr. Baptiste Joalland Nuwandi M. Ariyasingha Hassan R. Younes Shiraz Nantogma Dr. Oleg G. Salnikov Dr. Nikita V. Chukanov Dr. Kirill V. Kovtunov Prof. Igor V. Koptyug Prof. Juri G. Gelovani Prof. Eduard Y. Chekmenev 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2774-2781
Many MRI contrast agents formed with the parahydrogen-induced polarization (PHIP) technique exhibit biocompatible profiles. In the context of respiratory imaging with inhalable molecular contrast agents, the development of nonflammable contrast agents would nonetheless be highly beneficial for the biomedical translation of this sensitive, high-throughput and affordable hyperpolarization technique. To this end, we assess the hydrogenation kinetics, the polarization levels and the lifetimes of PHIP hyperpolarized products (acids, ethers and esters) at various degrees of fluorine substitution. The results highlight important trends as a function of molecular structure that are instrumental for the design of new, safe contrast agents for in vivo imaging applications of the PHIP technique, with an emphasis on the highly volatile group of ethers used as inhalable anesthetics. 相似文献
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