34094-21-8Relevant articles and documents
Synthesis and Photodimerization of 2- And 2,3-Disubstituted Anthracenes: Influence of Steric Interactions and London Dispersion on Diastereoselectivity
Geiger, Thomas,Haupt, Anne,Maichle-M?ssmer, C?cilia,Schrenk, Claudio,Schnepf, Andreas,Bettinger, Holger F.
, p. 10120 - 10135 (2019/08/26)
There is increased evidence that the effect of bulky groups in organic, organometallic, and inorganic chemistry is not only repulsive but can be attractive because of London dispersion interactions. The influence of the size of primary alkyl substituents in 2- and 2,3-positions of anthracenes on the diastereoselectivity (anti vs syn dimer) of the [π4s + π4s] photoinduced dimerization is investigated. The synthesis of the anthracene derivatives was achieved by Suzuki-Miyaura reaction of 2,3-dibromoanthracene with alkylboronic acids as well as by reduction of anthraquinones that were obtained from 2,3-disubstituted 1,3-butadienes and naphthoquinone followed by dehydrogenation. The mixtures of dianthracene isomers were analyzed with respect to the anti/syn-ratio of the products by X-ray crystallography and nuclear Overhauser effect spectroscopy. While for the 2,3-dimethylanthracene the anti and syn isomers were formed in equal amounts, the anti dimers are the major products in all other cases. A linear correlation (R2 = 0.98) between the steric size (Charton parameter) and the isomeric ratio suggests that the selectivity is dominated by classical repulsive steric effects. An exception is the iso-butyl substituent that produces an increased amount of the syn isomer. It is suggested that this is due to an exalted effect of London dispersion interactions.
Compounds with cardiac myosin activating function and pharmaceutical composition containing the same for treating or preventing heart failure
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Paragraph 0629-0631, (2017/02/02)
The present invention relates to a compound having a cardiotonic activating function and a pharmaceutical composition containing the same. The composition comprising the compound according to the present invention is effective in preventing or treating heart failure. In addition, the compound is represented by chemical formula 2 or is pharmaceutically acceptable salt thereof.COPYRIGHT KIPO 2016
The ouroborand: A cavitand with a coordination-driven switching device
Durola, Fabien,Rebek Jr., Julius
supporting information; experimental part, p. 3189 - 3191 (2010/07/15)
(Figure Presented) Molecular switch: The ouroborand coordinates an internal side chain in its cavity, just as it were swallowing its own tail. The presence or absence of zinc(II) in solution switches the cavity between open and closed states to external guests (see scheme: deep blue sphere: Zn).