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1.
Russian Journal of Organic Chemistry - A new series of thiazolo[4,5-d]pyrimidine-5-thione derivatives having indole and phenyl moieties were synthesized. Their structures were established by...  相似文献   
2.
Russian Journal of Organic Chemistry - A facile synthesis of a new series of 1,2,3-triazolyl nucleosides via one-pot click reaction is described. Acetylenic nicotinonitriles synthesized previously...  相似文献   
3.
Photoinduced birefringence in poly(methyl methacrylate) (PMMA), polymeric thin films doped with di-azo Sudan G was investigated. A pump-probe method was used to study the dynamic behavior of the birefringence. The mechanism for the inducement of birefringence is discussed in terms of the photoisomerization of the di-azo Sudan G molecules. The results showed that the dynamic evolution of the photoinduced birefringence was such that the average birefringence increased, saturated, and then decreased with respect to the laser pump intensity. Also, an exponential-like relationship was observed between both the saturation and the isotropic states of the averaged transmitted probe beam (expressing the residual anisotropy) and the birefringence on one hand, and the intensity amplitudes of the pumping powers on the other hand.  相似文献   
4.
An analytical method for the determination of buprofezin residues in cabbage and cauliflower was developed and validated using gas chromatography with ion trap mass spectrometry. The analyte protectant d ‐sorbitol was used at a concentration level of 0.5 mg mL?1 in acetonitrile instead of in matrix for constructing the calibration curves of the buprofezin standard. The average recoveries ranged from 91.3 to 96.8%, with an RSD of ≤2.7%. The limits of detection and quantitation of the method in cabbage and cauliflower were 1.3, 1.7 and 4.3, 6.2 μg kg?1, respectively. The residual levels and dissipation kinetics of buprofezin 25% wettabe powder in cabbage and cauliflower cultivated under open field conditions was investigated at the single (T1) and double (T2) recommended rates of application. Half‐life periods were found to be 1.73 and 2.1 days in cabbage, whereas in cauliflower, these values were 1.85 and 2.36 days at T1 and T2, respectively. Based on the dissipation study, and the maximum residue limit value of 0.05 mg kg?1, the proposed pre‐harvest interval of buprofezin in cabbage was 3–6 days and that in cauliflower was 4–10 days. The results showed that buprofezin is safe for application at both recommended application rates.  相似文献   
5.
Journal of the Iranian Chemical Society - Utility of 4-oxo-6-styryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 1 in synthesis of a new series of fused pyrimidines was described....  相似文献   
6.

Polyacrylonitrile/ferrocyanide composite incorporated with cetrimonium bromide (PFICB) was synthesized and evaluated as a novel bifunctional adsorbent for coremoval of Cs+ and HCrO4?. Results of the reaction time effect showed that adsorption of Cs+ and HCrO4? onto PFICB were rapid processes. The effect of the solution pH in the range 2.5–10 revealed that PFICB had the ability to simultaneously remove Cs+ and HCrO4?. The maximum adsorption capacity of PFICB was found to be 41.79 mg/g for Cs+ and 19.39 mg/g for HCrO4?. These values were compared with those reported in literature using other adsorbents.

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8.
2-Aminothiophene 3 was achieved through the one-pot multicomponent reaction of cycloheptanone, cyanoacetamide, elemental sulfur, and morpholine in ethanol. Diazotization of 2-aminothiophene 3 with NaNO2/HCl gave the corresponding diazonium salt 4 , that combined with the appropriate active methylene components; 5a , 5b , 7 , 11 , 13 , 16 , 18 , 21 , 9 , 19 , 22a , and 22b in pyridine (AcONa/EtOH) to form the corresponding hydrazones 6a , 6b , 8 , 10 , 14 , 15 , 17 , 20 , 23 , 24 , 25a , and 25b , respectively. Heating of compound 8 with malononitrile 9 in ethanol gave the thiazole 10 . Treatment of compound 10 , 25a , and 25b with hydrazine hydrate achieve the pyrazoles 12 , 27a , and 27b , respectively. Hydrazinolysis of compound 14 with hydrazine hydrate, followed by condensation of the obtained hydrazide 15 with acetylacetone 19 gave the pyrazole 20 . The recently orchestrated thiophenes were assessed for their cytotoxic action. The result revealed that compound 12 indicated comparable and better action towards HePG2, HCT-116, MCF-7, and PC3 cancer cell lines than Doxorubicin.  相似文献   
9.

A simple Pd2+ ligand exchanger was prepared and applied for isolation of aromatic heterocyclic sulfur compounds (S-PAHs) from petroleum condensate oil. The ligand exhibited excellent isolation efficiency and selectivity towards S-PAHs. The chromatograms of pre-isolated S-PAHs recorded by universal flame ionization (FID) and mass spectrum (MS) detections are similar to selective sulfur atomic emission detector chromatograms, indicated from traces or absence of hydrocarbons in FID and MS chromatograms. Nitrogen adsorption, electronic microscope, and X-ray diffraction techniques were employed to confirm the formation of capped Pd2+ nanoparticle dispersion within the silica framework. The results obtained revealed that Pd2+ ions exist as dispersed capped nanoparticles sized between 69 and 79 nm that can be rationalized for their enhanced isolation selectivity towards the S-PAH fraction of petroleum condensate oil.

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10.
The reaction of 3-hydroxy-3(2-oxocyclohexyl)indolin-2-one 1 with some active methylene, bidentates, phenylisocyanate, phenylisothiocyanate, carbon disulfide, benzaldehyde, ketoketene S,S-acetal, cyanoketene S,S-acetal, active halo compounds or benzylidenemalononitrile affords a series of new spiro heterocyclic systems.  相似文献   
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