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1.
X-ray structural analysis was used to determine the molecular and crystal structure of 2-(N-benzyl-N-phenylhydrazinoethylidene)-3-(2H)-benzo[b]thiophenone. The crystals are monoclinic, the space group isC2/c,a=16.022(6),b=11.202(3),c=22.111(4) Å, =81.08(3)°, and andZ=8. It was shown that the ability of hydrazones of a similar class to exhibit photochromic properties is a function of the steric stresses in the molecules and their confirmation.Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2805–2809, December, 1992.  相似文献   
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New photochromic fulgide, viz., 4-{1-[2-(anthracen-9-yl)-5-methyloxazol-4-yl]ethylidene}-3-isopropylidenetetrahydrofuran-2,5-dione, with fluorescent properties was synthesized. Studies by electronic, IR, and 1H NMR spectroscopy and X-ray diffraction demonstrated that this fulgide exists in the Z form. Light irradiation of its solutions at a wavelength of 365 nm causes Z/E isomerization giving rise to the thermally stable cyclic form. The latter is transformed into the starting E isomer under light irradiation at λ = 436 nm. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 97–101, January, 2006.  相似文献   
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Phenylmercury derivatives of 3-hydroxy-2-acetyl(benzoyl)benzo[b]thiophene and 3-hydroxy-1-methyl-2-carbaldehyde N-aryl- and N-alkylimines, to which a keto enamine structure with strong intramolecular coordination of the mercury atom and the carbonyl oxygen atom was assigned on the basis of the electronic and vibrational spectra, were synthesized. Compounds of the indole series fluoresce intensely with the usual values of the Stokesian shifts.See [1] for Communication 42.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 596–599, May, 1989.  相似文献   
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2-N-(4-Aminobenzo-15-crown-5)methylene-2,3-dihydrobenzo[b]thiophen-3-one and its acetyl derivative were synthesized. Their treatment with lithium, sodium, or potassium iodide in acetonitrile solution leads to formation of the corresponding crown-metal complexes. Irradiation of the acylated compounds at 436 nm induces NO migration of the acetyl group to give O-acyl isomer which is characterized by a considerable blue shift of the long-wave absorption band ( = 70 nm). The quantum yields of the photo- induced acylotropic reaction for the free ligand and its complexes with alkali metal cations change in the series: L > K+ > Na+ > Li+.  相似文献   
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Russian Chemical Bulletin - New potentially bioactive derivatives comprising spatially hindered pyrocatechol linked to hydrazine, acid hydrazides (including isoniazid), and acetylcysteine by a...  相似文献   
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Russian Chemical Bulletin - New potential biologically active derivatives, in which the sterically hindered pyrocatechol moiety is linked through a 2-thioacetyl covalent bridge to a number of...  相似文献   
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The reaction of 4-arylalkyl- and 4-arylthiosemicarbazides with aroyl isothiocyanates gave substituted 1,2-bis(thiocarbamoyl)hydrazines, which readily cyclize to give previously unreported 4-aroyl 5-arylalkyl- and 4-aroyl-5-arylamino-2H-1,2,4-triazole-3-thiones, respectively. A spectral study of 9-anthrylmethylthiosemicarbazides and derived dihydrotriazolethione indicated the chemosensor activity of these compounds relative to a cation series.  相似文献   
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