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71.
J.S. Yadav B.V. Subba Reddy A.K. Basak A.V. Narsaiah A. Prabhakar B. Jagadeesh 《Tetrahedron letters》2005,46(4):639-641
Baylis-Hillman acetates undergo SN2′ allylic substitution with indoles in the presence of 20 mol % of indium tribromide under mild conditions to afford a new class of substituted indoles in high yields with (E)-stereoselectivity. The stereochemistry of the products was assigned by various NMR experiments. 相似文献
72.
A highly efficient and stereoselective synthesis of (2R,3R,4R)-HMP is disclosed employing the sulfinyl group as an internal nucleophile to functionalize an olefin in the key step of the reaction sequence. The proline ring is elaborated by a (4C+N) cyclization. 相似文献
73.
Spin configuration of Gd13 clusters 总被引:1,自引:0,他引:1
74.
Andhe V. Narender Reddy Charles Y. Fiakpui David P. Czajkowski Paul Spevak Jadwiga Kaleta Ronald G. Micetich Samarendra N. Maiti 《Chemistry of Heterocyclic Compounds》1998,34(11):1289-1295
A new series of 2-spiro(2,2-diphenylcyclopropane) cephalosporin sulfones was synthesizes as potent human leukocyte elastase inhibitors.SynPhar Laboratories Inc., #2 Taiho Alberta Centre, 4290-91A Street, Edmonton, Canada T6R 5V2. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1517–1523, November, 1998. 相似文献
75.
Oludotun A. Phillips Eduardo L. Setti Andhe V. N. Reddy Ronald G. Micetich Chieko Kunugita Akio Hyodo Samarendra N. Maiti 《Chemistry of Heterocyclic Compounds》1998,34(11):1319-1323
Two monobactam derivatives, potassium 4-methyl-(3E)-[(thien-2-yl)methylene]-2-azetidinone-1-sulfonate and its (3Z)-isomer, were prepared and evaluated for their -lactamase inhibitory activities. These compounds were devoid of -lactamase inhibitory activity.SynPhar Laboratories Inc., #2, 4290-91A Street, Edmonton, Alberta T6E 5V2, Canada. Tokushima Research Institute, Taiho Pharmaceutical Co., Ltd., 224-2 Ebisuno Hiraishi, Kawauchi-cho, Tokushima 771-01, Japan. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1548–1552, November, 1998. 相似文献
76.
Application of sodium metaperiodate for the determination of ribavirin in pharmaceutical formulations 总被引:1,自引:0,他引:1
Three simple and sensitive visible spectrophotometric methods (A-C) have been described for the assay of ribavirin either in pure form or in pharmaceutical formulations. They are based on the oxidation of ribavirin with excess sodium metaperiodate and estimating either the products formed (dialdehyde with MBTH, method A; iodate with metol-sulphanilamide, in the presence of Mo(VI) and iodide, method B) or the amount of periodate consumed (celestine blue in the presence of telurium (IV), method C). All of the variables have been optimized and the reaction mechanisms presented. The concentration measurements are reproducible within a R.S.D. of 1.0%. Recoveries are 99.2-101.2%. 相似文献
77.
K. Premchand B. Seetharami Reddy B. Mallikarjuna Rao K. Parthasaradhi M. V. R. Murti K. S. Rao 《Il Nuovo Cimento D》1993,15(1):73-76
Summary An attempt is made to study theK
α
L
1 satellite multiplet structure of chlorine atoms in different compounds by photon excitation. A comparison of the averageK
α
L
1 group energy shift from the diagram line with those based on Dirac-Fock evaluations with different number ofM-shell electrons shows a reasonable agreement. The
intensity ratios are found to be higher than those studied in Mg compounds in general. 相似文献
78.
S Chandrasekhar G Chandrashekar B Nagendra Babu K Vijeender K Venkatram Reddy 《Tetrahedron letters》2004,45(28):5497-5499
A facile synthesis of symmetrical and unsymmetrical ethers is achieved by reductive coupling of carbonyl compounds with alkoxysilanes. This reaction is performed using inert polymethylhydrosiloxane as the hydride source and B(C6F5)3 as the catalytic activator of the PMHS. 相似文献
79.
[reaction: see text] Chiral beta-syn-alkoxyhomoallylic alcohols derived from alkoxyallylboration of aldehydes upon oxidation provided the corresponding chiral ketones. Chelation-controlled nucleophilic addition to these ketones occurred in a highly stereoselective manner to afford anti-homoallylic tertiary alcohols. This methodology has been applied for the synthesis of the C(1)-C(11) subunit of C(8)-epi-fostriecin. 相似文献
80.
S. Pitchumani C. Rami Reddy S. Rajadurai 《Journal of polymer science. Part A, Polymer chemistry》1982,20(2):277-282
Ethyl acrylate (EA) and n-butyl methacrylate (n-BMA) copolymers were prepared in solution and the composition of the copolymer samples was estimated by 1H-NMR spectroscopic techniques. Because the characteristic signals, which vary with the composition of the copolymer, were absent, the ratio of intensities of down-field protons to that of the total protons was used for the estimation of copolymer composition. Reactivity ratios were calculated from these values by using the Kelen-Tudos differential linear equation. 相似文献