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91.
92.
K. Nagarajan M. Bhupathy Rajendra Prasad Ziley Singh V. Venugopal D.D. Sood 《Thermochimica Acta》1980,36(1):85-89
The thermal decomposition kinetics of Pr2(SO4)3 to Pr2O2SO4 have been studied by isothermal weight change determination. The reaction was found to obey a linear law up to α = 0.5; beyond α = 0.5 it could be described as a phase-boundary controlled process. A dependence of the activation energy upon the sample weight was observed. The changes in surface area and density which occur during the decomposition are also given. 相似文献
93.
A novel synthetic approach is described to incorporate one more carbon atom at C-2 position of phospholane oxides as homologated allylic alcohol by treatment of erythro-2,3-epoxy-3-methylphospholane 1-oxides with excess of dimethylsulfonium methylide. 相似文献
94.
The Raman phonon spectroscopic study shows that the photodimerization of 2,6-dimethyl-p-benzoquinone. In the solid state is initially a homogeneous reaction but later becomes heterogeneous as the product accumulates. The Ion-temperature electronic absorption spectrum reveals that the reaction is phonon assisted by a polaron formed due to a strong electron- phonon coupling in the cxcited 1nπ* state. 相似文献
95.
[reaction: see text] The studies in the Diels-Alder reactions of 5-methoxy-masked o-benzoquinone (1a, R = OMe) and simple dissymmetric 2,4-cyclohexadienones 1b-e with methyl vinyl ketone, styrene, and benzyl vinyl ether are described. The dienones 1b-e reacted with dienophiles to form syn adducts (dienophile approach is syn to allylic methoxy group) exclusively. 相似文献
96.
1,4-Disubstituted 1,2,3-triazoles are obtained in excellent yields via a three-component coupling of secondary alcohols, alkynes and trimethylsilyl azide (TMSN3). This one-pot reaction occurs through in situ generation of an azide from the alcohol and TMSN3, followed by 1,3-dipolar cycloaddition of the terminal alkyne to afford the corresponding disubstituted triazoles. 相似文献
97.
New PNA analogues derived from aminoethylpyrrolidin-5-one backbone show stabilization of aepone-PNA:DNA hybrids and destabilization of the corresponding RNA hybrids compared to unmodified PNA. 相似文献
98.
J. V. N. Vara Prasad 《Journal of heterocyclic chemistry》1996,33(6):1599-1603
A series of 2-aryl-4-hydroxy-5-thio substituted 1,3-thiazin-6-ones were synthesized for human immunodeficiency virus-1 protease inhibition. These compounds were synthesized by the treatment of 4-hydroxy-5-thio substituted-1,3-thiazin-6-ones with the corresponding sulfenyl chlorides. The products were obtained in good isolated yields, inspite of the presence of bulkyl substitutents at the ortho position of phenyl sulfenyl chloride portion. 相似文献
99.
Condensation of azetidinones 2a and 2b with mercaptan 3 gave respectively compound 10 or a 1:1 mixture of 17 and 17 ′. Bromination of 10 , afforded cis and trans-bromohydrins 13a and of 17 and 17 ′ cis and trans-bromohydrins 18a . Acetylation and reduction with zinc and acetic acid of these bromohydrins gave cephems 4a or 4b and 4b ′ respectively. 相似文献
100.
M. V. R. Prasad 《Journal of Radioanalytical and Nuclear Chemistry》1997,226(1-2):175-179
A novel electrolytic method has been developed for destroying organic matter in urine. A combination of potassium permanganate, sulfuric acid and nitric acid has yielded about 99% destruction in initial organic content of urine within two hours when electrolysis is carried out with an applied voltage of about 2.5 V, while maintaining a current density of 8.23 mA/cm2 at 373 K. 相似文献