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1.
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
2.
The first example of the use of (195)Pt PGSE diffusion data (D values) to recognize the solvent dependence of aggregation of the hexachloroplatinate dianion in Na(2)PtCl(6) (1) and in H(2)PtCl(6) (2) is reported. In water, the ions are separated; however, in methanol the D values suggest ion pairing and/or aggregation. Additional (1)H and (31)P diffusion data for organometallic Pt complexes trans-PtX(Aryl)(L)(2) (where L = PEt(3) or PPh(3)) and Pt(C(7)H(4)O(2))(L(1))(L(2)) (where L(1) and L(2) = a variety of ligand types) reveal that phenyl phosphines afford relatively large hydrodynamic radii r(h). The presence of a substituent on the aryl ligand of PtX(Aryl)(L)(2) does not markedly affect the D values, whereas a substituent of similar size added to a PPh(3) group in Pt(C(7)H(4)O(2))(L(1))(L(2)) markedly changes both D and r(h) values. There is only a small concentration dependence of the D values in PtX(Aryl)(L)(2) on changing from 2 to 10 mM. 相似文献
3.
A simple, efficient, regioselective and environmentally safe method for oxybromination of activated aromatics catalyzed by HZSM-5 is reported. The electrophilic substitution of bromine generated from KBr using HZSM-5 as a catalyst and H2O2 as an oxidant. 相似文献
4.
Arun Kumar Macharla Rohitha Chozhiyath Nappunni Narender Nama 《Tetrahedron letters》2012,53(11):1401-1405
An efficient protocol for the synthesis of vicinal bromohydrins and dibromides from olefins is presented. Various olefins are regio- and stereoselectively hydroxybrominated and dibrominated with anti fashion, following Markonikov’s rule, using eco-friendly, non-toxic, and stable reagents such as NH4Br and oxone® in CH3CN/H2O (1:1) and CH3CN without employing catalyst in moderate to excellent yields. Bromohydrins are formed instantaneously. 相似文献
5.
Jitender Gaur Shilpa Jain Rohit Bhatia Arun Lal Narender Kumar Kaushik 《Journal of Thermal Analysis and Calorimetry》2013,112(2):1137-1143
We demonstrate synthesis of water insoluble, novel copolymer PA1 from condensation of glyoxal dihydrazone and glyoxal dihydrazone bis(dithiocarbamate) monomers having high capacity to remove metal ions from aqueous solution. The presence of a high atomic percentage of nitrogen and sulfur atoms in PA1 leads to strong ligating ability with metal ions. The monomers and the polymer have been characterized by FTIR, UV–Visible spectroscopy, CHNS elemental analysis, NMR, MALDI-MS, and TG/DTA. As a proof of concept, the PA1 is tested for its ability to remove heavy metal ions Cu2+, Co2+, Fe2+, Ni2+, Mn2+, and CrO 7 2? from aqueous solutions. PA1 efficiently removed metals ions from the metal solutions. The highest absorption ability has been observed toward the iron salts where 0.969 g metal salt is absorbed by 1 g polymer. This study has implication for inexpensive and efficient polymer for purification of water. 相似文献
6.
M. Narender M. Somi Reddy N. Srilakshmi Krishnaveni K. Surendra Y. V. D. Nageswar 《合成通讯》2013,43(10):1463-1470
A mild and efficient method for the regeneration of carbonyl compounds from oximes at room temperature in impressive yields has been developed using iodosobenzene/KBr in the presence of β‐cyclodextrin in water. 相似文献
7.
An efficient, simple, and practical method has been developed for the deprotection of prenyl, geranyl, and phytyl ethers and esters of aromatic and aliphatic compounds using borontrifluoride–etherate (BF3 · OEt2) at room temperature in good to excellent yields for the first time. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
8.
Krishnaiah Atmakur Narender Reddy Emmadi Sridhar Balasubramanian 《Journal of heterocyclic chemistry》2013,50(3):513-518
A series of novel fluorinated 11H‐azaindolo[3,2‐c]isoquinolines ( 7 ) have been synthesized starting from 2(1H)pyridones ( 1 ) via azaindoles ( 5 ). Initially, compound 1 was treated with POCl3/DMF, and the resulting compound 2 was reacted with benzylamine to obtain compounds 3 that were subjected to cyclization after protecting the secondary amine to get azaindoles ( 5 ). Further, compounds 5 were subjected to cyclization as per Pictet–Spengler reaction condition. However, it was not successful. Subsequently, the azaindoles ( 5 ) were acetylated and then cyclized to give title compounds 7 . These compounds are new and well characterized by spectral data. 相似文献
9.
Biswanath Das Yallamalla Srinivas Chittaluri Sudhakar Kongara Damodar Ravirala Narender 《合成通讯》2013,43(2):220-227
Bromination of alkenes and alkynes has efficiently been carried out at room temperature in short reaction times using KBr and diacetoxy iodobenzene in CH2Cl2-H2O (1:1) to prepare the corresponding trans-dibromo compounds in excellent yields. 相似文献
10.
A convenient one-pot method has been developed for the synthesis of substituted acetylchromans involving the condensation of polyhydroxyacetophenone with isoprene and long chain allylic alcohol (phytol) in the presence of borontrifluoride etherate (BF3-Et2O). 相似文献