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11.
Shibo Xu Kazutaka Takamatsu Prof. Dr. Koji Hirano Prof. Dr. Masahiro Miura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(40):9400-9404
A NiCl2(PEt3)2-catalyzed regioselective C−H coupling of 8-aminoquinoline-derived benzamides with oxetanes has been developed. The reaction proceeds with concomitant removal of the 8-aminoquinoline auxiliary to directly form the corresponding seven-membered benzolactones, which frequently occur in natural products and bioactive molecules. Additionally, no stereochemical erosion is observed during the course of the reaction, and the use of enantioenriched and substituted oxetane thus provides a new avenue to the optically active benzolactone. 相似文献
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Sina Hedayat 《代数通讯》2017,45(4):1711-1718
A proper ideal of a commutative ring is called pseudo-irreducible if it cannot be written as a product of two comaximal proper ideals. In this paper, we give a necessary and su?cient condition for every proper ideal of a commutative ring to be a product of pairwise comaximal pseudo-irreducible ideals. Examples of such rings include Laskerian rings, or more generally J-Noetherian rings and ZD-rings. We study when certain classes of rings satisfy this condition. 相似文献
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Hans Schoutens 《代数通讯》2017,45(1):262-274
We prove Hochster’s small maximal Cohen–Macaulay conjecture for three-dimensional complete F-pure rings. We deduce this from a more general criterion, and show that only a weakening of the notion of F-purity is needed, to wit, being weakly F-split. We conjecture that any complete ring is weakly F-split. 相似文献
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A right R-module M is called simple-direct-injective if, whenever, A and B are simple submodules of M with A?B, and B?⊕M, then A?⊕M. Dually, M is called simple-direct-projective if, whenever, A and B are submodules of M with M∕A?B?⊕M and B simple, then A?⊕M. In this paper, we continue our investigation of these classes of modules strengthening many of the established results on the subject. For example, we show that a ring R is uniserial (artinian serial) with J2(R) = 0 iff every simple-direct-projective right R-module is an SSP-module (SIP-module) iff every simple-direct-injective right R-module is an SIP-module (SSP-module). 相似文献
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Jairo Z. Goncalves 《代数通讯》2017,45(12):5193-5201
Let k(t) be the field of rational functions over the field k, let σ be a k-automorphism of K = k(t), let D = K(X;σ) be the ring of fractions of the skew polynomial ring K[X;σ], and let D? be the multiplicative group of D. We show that if N is a noncentral normal subgroup of D?, then N contains a free subgroup. We also prove that when k is algebraically closed and σ has infinite order, there exists a specialization from D to a quaternion algebra. This allows us to explicitly present free subgroups in D?. 相似文献
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In [1], Bannai presents a fusion condition and uses this to consider central Schur rings (S-rings) over the simple groups PSL(2,q) where q is a prime power. In this paper, we concretely describe all such S-rings in terms of symmetric S-rings over cyclic groups. The final section discusses counting these. 相似文献
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Alexander A. Kirichok Dr. Iryna Shton Dr. Maria Kliachyna Dr. Iryna Pishel Dr. Pavel K. Mykhailiuk 《Angewandte Chemie (International ed. in English)》2017,56(30):8865-8869
The 2-substituted piperidine core is found in drugs (18 FDA-approved drugs), however, their spirocyclic analogues remain unknown. Described here is the synthesis of spirocyclic analogues for 2-substituted piperidines and a demonstration of their validation in drug discovery. 相似文献