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Piotr Kus 《Journal of mass spectrometry : JMS》1991,26(7):653-654
The mass spectral fragmentation of 23 dithia [3.3]naphthalenophanes is discussed. The most characteristic species for these compounds are the M+ ion and ions at m/z 115, 135 (or 136), 141, 155 (or 154) and 185. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(30):8991-8995
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
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Babett Krauss Clemens Mügge Burkhard Ziemer Adolf Zschunke Friedrich Krech 《无机化学与普通化学杂志》2001,627(7):1542-1552
1‐Phosphabicyclo[3.2.1]octanes 1‐Phosphabicyclo[3.2.1]octane has been obtained by free‐radical cyclization of (2‐vinyl‐4‐pentenyl)‐phosphane in the presence of AIBN. Another approach to 1‐phosphabicyclo[3.2.1]octanes involves free‐radical cyclization of 2‐methyl‐4‐(2‐propenyl)‐phospholane synthesized by the reaction of [2‐(2‐propenyl)‐4‐pentenyl]‐phosphane with KPH2/[18]crown‐6 in THF. The bicyclic phosphanes are characterized by reactions with CS2, selenium, sulfur, NO, CH3I, and HSO3F, respectively, structural and analytical data as well as 1H, 13C, 31P, 77Se NMR spectral measurements. The steric crowding of the phosphanes as complex ligands has been estimated from 31P–1H coupling constants according to the Tolman model. The configuration of the methyl substituents as well as the conformation of the six‐membered ring were determined by NMR parameters (coupling constants, noe's) and proved by X‐ray crystal structure analysis. 相似文献
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《Journal of heterocyclic chemistry》2018,55(1):91-96
Reaction of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione ( 1 ) with two equivalents of some 6‐aminouracils (or 6‐amino‐2‐thiouracil) generates spirocyclic tetrahydrobenzo[if]quinolizines ( 7 ). The one‐pot, three‐component reaction of amido ketone ( 1 ) with 6‐aminouracil (or 6‐amino‐2‐thiouracil) and a cyclic six‐membered 1,3‐diketone produces spirocyclic tetrahydropyrrolo[3,2,1‐ij]quinolinones ( 15 ). 相似文献
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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
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Babett Krauss Clemens Mügge Adolf Zschunke Friedrich Krech Michaela Flock 《无机化学与普通化学杂志》2002,628(3):580-588
1‐Phosphabicyclo[2.2.1]heptanes Exo‐endo‐ and exo‐exo‐2.6‐dimethyl‐1‐phosphabicyclo [2.2.1]heptane have been obtained by cyclization of 2‐methyl‐4‐(2‐propenyl)phospholane in the presence of the complex base, sodium salt of diethylenglycolmonoethylether ‐ sodium amide in THF (NAMEDEG). The bicyclic phosphanes are characterized by reac‐tions with selenium, sulfur, (CH3)2SeO, CH3I and HSO3F, respectively, elemental analysis, X‐ray crystal structure analysis as well as 1H, 13C, 31P NMR spectral measurements. The steric demand of these phosphanes as complex ligands has been estimated from the P, H coupling constants of the phosphonium fluorosulphates according to the Tolman model. The phosphane selenides were found to display the lowest values for the 1J(Se, P) coupling constant, found up to now for alicyclic and cyclic aliphatic tertiary phosphane selenides. The nJ(P, H)‐ and nJ(H, H)n=2, 3 coupling constants have been extracted from the proton spectra at 600 MHz by computerized analysis. 相似文献