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51.
A procedure for the selective deprotection of p-methoxybenzyl ethers using catalytic amounts of DDQ and of sodium nitrite, with oxygen as the terminal oxidant, is reported. 相似文献
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Jon Babi Linglan Zhu Angela Lin Azalea Uva Hana El-Haddad Atang Peloewetse Helen Tran 《Journal of polymer science. Part A, Polymer chemistry》2021,59(21):2378-2404
Sequence-defined polymers can be programmed to self-assemble into precise nanostructures for applications in biosensing, drug delivery, optics, and molecular computation. Inspired by the natural self-assembly processes present in biological protein and DNA systems, sets of molecular design rules have emerged across materials classes as instructions to build a variety of tunable structures. This review highlights recent advances in self-assembled sequence-defined and sequence-specific polymers across peptides, peptoids, DNA, and non-biological synthetic materials, with a focus on synthesis, assembly processes and overall structure. Specifically, these self-assembled structures are free-floating, as such constructs can potentially serve as a platform for the aforementioned applications. Emphasis is placed on the molecular design of polymers that self-assemble into zero-dimensional, one-dimensional, two-dimensional, or three-dimensional nanostructures. With the development of automated syntheses and increasing control over self-assembly, future work may focus on emerging classes of compatible hybrid materials with exciting directions toward new architectures and applications. 相似文献
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Analysis of non‐derivatised bacteriohopanepolyols by ultrahigh‐performance liquid chromatography/tandem mass spectrometry
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Iran Sheikhshoaie Helen Stoeckli-Evans Alireza Akbari S. Ali Yasrebi S. Yousef Ebrahimipour 《Arabian Journal of Chemistry》2012,5(2):173-178
The crystal and molecular structure of methanol {E-N′-(2-hydroxybenzlidene)benzohydrazido}dioxidomolybdenum (VI) was determined by single crystal X-ray diffraction. B3LYP/DZP basis set theoretical calculations nicely reproduce the X-ray experimental geometry. The obtained results are discussed in connection with the electronic and structural properties of the compound. 相似文献
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Helen M. Nanobashili S. E. Gvilava M. V. Panchvidze 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract The development of the scientific principles of the protective action of various compounds and in particular sulphur organic compounds for irradiation is one of the most actual problem in the modern radiation chemistry and radiobiology. With that in view the radiolysis of the various sulphur organic compounds in stationary and pulse conditions both in pure state and in model systems has been studied and the main regularities of their radiolytic behaviour are established. The primary processes of the radiolysis of sulphurorganic compounds containing SHY -S-, NH2, COOH, C H functional groups are investipated and the radical products of the radiolysis- anion- andcation-radicals, thiyl and alkyl radicals are identified and their reactivity is studied in irradiation field. 相似文献