Results 1 to 10 of about 207,671 (274)

Enantioselective construction of cyclic quaternary stereocenters via dinuclear copper catalyzed asymmetric [3 + 2] propargylation/annulation [PDF]

Nature Communications
While copper-catalyzed asymmetric propargylic substitution has emerged as a versatile tool for constructing chiral propargylic frameworks, its application in forging cyclic chiral quaternary carbon centers remains a significant synthetic challenge.
Lili Shao, Zekai Fang, Peng Liu, Yu Lan, Qilong Cai, Xiaoming Wang   +5 more
doaj   +2 more sources

A Natural Approach to Solving the Traveling Salesman Problem

Кібернетика та комп'ютерні технології, 2023
Introduction. The traveling salesman problem is a transport-type problem. It is natural to use a method based on the technology for solving transport problems to solve it.
Dmitri Terzi
doaj   +1 more source

Error correction by Reed–Solomon codes using its automorphisms

Весці Нацыянальнай акадэміі навук Беларусі: Серыя фізіка-тэхнічных навук, 2021
The article explores the syndrome invariants of АГ-group of automorphisms of Reed–Solomon codes (RS-codes) that are a joint group of affine and cyclic permutations. The found real invariants are a set of norms of N Г-orbits that make up one or another АГ-
V. A. Lipnitsky, S. I. Semyonov
doaj   +1 more source

Three-Component Condensation of β-Ketonitriles, 4-Fluorobenzaldehyde, and Secondary Cyclic Amines

Reactions, 2022
A new three-component condensation of β-ketonitriles, 4-fluorobenzaldehyde, and secondary cyclic amines was developed. A possible reaction mechanism has been proposed including Knoevenagel condensation followed by aromatic nucleophilic substitution.
Dmitry V. Osipov, Kirill S. Korzhenko, Vitaly A. Osyanin   +2 more
doaj   +1 more source

Amide-to-ester substitution as a stable alternative to N-methylation for increasing membrane permeability in cyclic peptides

Nature Communications, 2023
Naturally occurring peptides with high membrane permeability often have backbone ester bonds. Here, the authors investigated the effect of an amide-to-ester substitution on membrane permeability of peptides and found the substitution is useful for ...
Yuki Hosono, Satoshi Uchida, Moe Shinkai, Chad E. Townsend, Colin N. Kelly, Matthew R. Naylor, Hsiau-Wei Lee, Kayoko Kanamitsu, Mayumi Ishii, Ryosuke Ueki, Takumi Ueda, Koh Takeuchi, Masatake Sugita, Yutaka Akiyama, Scott R. Lokey, Jumpei Morimoto, Shinsuke Sando   +16 more
doaj   +1 more source

Syndrome spectrums of error orbits in RS-codes

Системный анализ и прикладная информатика, 2020
This article is devoted to the research of the properties of syndromes of errors in Reed-Solomon codes. RS-codes are built on non-binary alphabets. So, unlike BCH-codes, RS-codes contain an extremely large variety of correctable errors.
V. A. Lipnitski, S. I. Semyonov
doaj   +1 more source

Implementation of a nonlinear transformation of a substitution in the form of elements of a numbering system of a number of factorial sets

Безопасность информационных технологий, 2021
The paper investigates a nonlinear substitution transformation, presented as an element of the number system of factorial sets. This approach takes into account the characteristic features of substitutions and al-lows you to minimize the amount of memory
Alexander P. Martynov, Dmitry B. Nikolaev, Kirill D. Ermakov   +2 more
doaj   +1 more source

The automorphisms and error orbits of Reed – Solomon codes

Доклады Белорусского государственного университета информатики и радиоэлектроники, 2020
The purpose of this work with its results presented in the article was to develop and transfer to the class of Reed – Solomon codes (RS-codes) the basic provisions of the theory of syndrome norms (TNS), previously developed for the noise-resistant coding
S. I. Semyonov, V. A. Lipnitsky
doaj   +1 more source

Single nucleotide polymorphisms of human STING can affect innate immune response to cyclic dinucleotides. [PDF]

PLoS ONE, 2013
The STING (stimulator of interferon genes) protein can bind cyclic dinucleotides to activate the production of type I interferons and inflammatory cytokines.
Guanghui Yi, Volker P Brendel, Chang Shu, Pingwei Li, Satheesh Palanathan, C Cheng Kao   +5 more
doaj   +1 more source

Hypervalent Iodine-Mediated Diastereoselective α-Acetoxylation of Cyclic Ketones

Frontiers in Chemistry, 2020
A binary hybrid system comprising a hypervalent iodine(III) reagent and BF3•OEt2 Lewis acid was found to be effective for the diastereoselective α-acetoxylation of cyclic ketones.
Jiashen Tan, Weiqin Zhu, Weiping Xu, Yaru Jing, Yaru Jing, Zhuofeng Ke, Yan Liu, Keiji Maruoka, Keiji Maruoka   +8 more
doaj   +1 more source