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41.
Russian Chemical Bulletin - The reactions of 3-acetoxy-2-acetyl(cyanoacetyl)aminoisoindolin-1-one (1) with o-tosylaminobenzaldehyde and o-mesylaminobenzaldehyde morpholinals lead to a mixture of...  相似文献   
42.
43.
Photochromic indoline spiropyrans with carbohydrazide substituents in the pyrano[2,3-f]chromene moiety of the molecule have been synthesized. These compounds exhibit inochromic properties and are chromogenic (“naked-eye”) and fluorogenic chemosensors for lanthanide cations.  相似文献   
44.
The novel heterocyclic fulgide, 3-(1-methylethylidene)-4-[1-(2-methylthieno[3,2-b]-[1]benzothiophen-3-yl)ethylidene]dihydrofuran-2,5-dione, was obtained and isolated as a Z-isomer. Its structure was confirmed by electronic absorption spectroscopy, 1H NMR spectroscopy, and X-ray diffraction analysis. The novel thienothiophene fulgide is photochromic in both solutions and the crystalline state. Its colored cyclic form resists photodegradation and is thermally stable. When benzothiophene is annulated with the thienyl fragment, the long-wavelength absorption peak of the cyclic isomer of the novel fulgide experiences a bathochromic shift compared to the earlier described 3-thienylfulgide. The TD B3LYP/6-311G**-calculated spectroscopic characteristics of the fulgide isomers suggest the formation of their photostationary mixture under irradiation with λ = 365 nm. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2318–2324, December, 2007.  相似文献   
45.
Novel nonsymmetric dihetarylethenes 3-(5-methoxy-1,2-dimethyl-1H-benzo[g]indol-3-yl)-4-(3-thienyl)-furan-2,5-dione and 1-alkyl- and 1-aryl-3-(5-methoxy-1,2-dimethyl-1H-benzo[g]indol-3-yl-4-(3-thienyl)-1(H)-pyrrole-2,5-diones were synthesized. The substitution of the furandione moiety for pyrroledione gives rise to the radiation and photochemical channels of deactivation of the electron excitation energy of dihetarylethenes. The products of photolysis of pyrrolediones undergo recyclization in both the ground and excited states.  相似文献   
46.
A new spirobenzopyranindoline containing a rhodamine fragment bonded by an azomethine spacer with the benzopyran fragment was synthesized based on 6-formyl-7-hydroxy-substituted spiropyran; the new compound exhibited complexation properties in solutions.  相似文献   
47.
The results are presented of a calculation of cavity flow in an axisymmetric channel with an annular obstacle. The problem was suggested to the author by G. B. Tsvetnov.The problem is solved by the method published in [1, 2].  相似文献   
48.
Russian Journal of General Chemistry - Indolyl(thienyl)maleimides with terpyridine receptor in the bridge part have been synthesized. Irradiation of their toluene solutions with light at λ =...  相似文献   
49.
A mathematical model of the air flow in the human nasal cavity is developed under the assumption of a turbulent viscous air flow. The shape of the nasal cavity is modeled with the use of the Gambit graphical software system and tomography data. A numerical solution is obtained by using the Fluent commercial software system. Calculations are performed for various variants of construction of the human nasal cavity.  相似文献   
50.
A convenient, one-pot synthesis of N-isatinylmethylthioacetic acid and several of its derivatives, as potential anticancer agents, by reactions of N-(hydroxymethyl)isatins with Bunte salts in TFA is described. The reactions involve attack of these salts on the S(II) atom by C-electrophilic species generated from hydroxy derivatives.  相似文献   
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