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1.
Phenyl vinyl sulfonate reacts with various alkyl furan derivatives under mild conditions to produce excellent yields of the corresponding cycloadducts. 相似文献
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Omar Deeb Prof. Monika Leibscher Dr. Jörn Manz Prof. Wulf von Muellern Tamar Seideman Prof. 《Chemphyschem》2007,8(2):322-328
We propose an approach for separating nuclear spin isomers with coherent light and illustrate it by numerical calculations using fulvene as a model system. The scheme employs the equivalence of torsion and interchange of equivalent H-atoms in a class of molecules of which fulvene is a simple example. The exchange symmetry couples with the rotational symmetry to produce a spatial distinction between the two photo-excited nuclear spin isomers, and wavepacket interferometry is applied to separate the species. 相似文献
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Fatma El-Mariah Mona Hosny Ali Deeb 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2505-2517
A series of 3-substituted pyridazino[3′,4′:3,4]pyrazolo[5,1-c]-1,2,4-triazens have been synthesized starting from the 3-carboxylic acid derivative 2. The reaction of the acid chloride 3 with amines gave the corresponding anilides 4. The reaction of 2 with ethyl chloroformate and sodium azide in the presence of triethyl amine gave the carbonyl azide 5, which underwent a Curtius rearrangement in boiling ethanol to afford the carbamate 6, which converted to the 3-amino derivative 7 upon alkaline hydrolysis, and the reaction with acid chloride resulted in N-substituted products 9. On other hand, the reaction of the carboxylic acid 2 with POCl3 and thiosemicarbazide afforded 2-amino-1,3,4-thiadiazole derivative 13. The condensation of 13 with aldehydes furnished 14 in a good yield. The products were screened for their antimicrobial activity against six microorganisms. 相似文献
5.
Ali Deeb 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):637-650
AbstractThis review describes the synthesis and reactions of 5-aminothieno[2,3-c]pyridazine-6-carbonitriles as a building blocks for the synthesis of polyfunctionalized heterocyclic compounds. The antimicrobial activity of some compounds are discussed. 相似文献
6.
Ali Deeb Mahmoud Kotb Mohamed El-Abbasy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2245-2252
3-Substituted pyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine-2,4-di-ones and 3-amino-2-methylpyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine-4-ones were synthesized starting from ethyl 5-aminothieno[2,3-c] pyridazine-6-carboxylate 1. Reaction of amino ester 1with phenyl isothiocyanate affords thiourea derivative 10which undergo further transformation to the related fused heterocyclic systems. 相似文献
7.
Form factor axioms are derived in two dimensional integrable defect theories for matrix elements of operators localized both in the bulk and on the defect. The form factors of bulk operators are expressed in terms of the bulk form factors and the transmission factor. The structure of the form factors of defect operators is established in general, and explicitly calculated in particular, for the free boson and for some operator of the Lee–Yang model. Fusion method is also presented to generate boundary form factor solutions for a fused boundary from the known unfused ones. 相似文献
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Sami El Deeb 《Chromatographia》2010,71(9-10):783-787
An LC method was developed and validated for the enantioselective separation and enantiomeric impurity quantitation of atenolol. Separation of the atenolol enantiomers on the Chirobiotic V2 (150 mm × 4.6 mm, 5 μm) column was best achieved using a ternary mobile phase of methanol–acetonitrile-triethylamine acetate 0.5% (w/v), pH 4.5 in a ratio of (45:50:5; v/v/v). Good resolution value of R s = 3 was obtained at a flow rate of 1 mL min?1 within a total run time of less than 40 min. Peak identification was achieved using the standard reference of individual enantiomers. The peak of the impurity was eluted in front of the peak of the main enantiomer. Detection was performed by UV at 226 nm. Within and between day’s repeatabilities for both retention time and peak area were investigated at three concentration levels and found to be low. The method was also found to be efficient for the determination of atenolol enantiomeric impurity. An impurity quantitation level of (R)-atenolol down to 0.08% relative to the main enantiomer (S)-atenolol was found possible. 相似文献