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排序方式: 共有318条查询结果,搜索用时 15 毫秒
121.
Thirumalai Dhakshanamurthy Gajalakshmi Shanmugam 《Research on Chemical Intermediates》2020,46(5):2657-2668
Research on Chemical Intermediates - An efficient and simple method for the synthesis of xanthene derivatives by using iron oxide nanoparticles (NPs) as a catalyst has been investigated. Synthesis... 相似文献
122.
Shanmugam Thiyagarajan Linda Gootjes Willem Vogelzang Jing Wu Jacco van Haveren Daan S. van Es 《Tetrahedron》2011,67(2):383-389
An efficient route towards the synthesis of 2,5-diamino-2,5-dideoxy-1,4-3,6-dianhydroiditol 4 has been developed resulting in significant improvements in both isolated yields and purity when compared to literature procedures. As a consequence, resin-grade 2,5-diamino-2,5-dideoxy-1,4-3,6-dianhydroiditol 4 has become available for laboratory scale step-growth polymer synthesis. Additionally, an interesting renewable chiral 2-amino-2-deoxy-1,4-3,6-dianhydroiditol 10, has been isolated. 相似文献
123.
Muthusamy BoominathanMuthupandi Nagaraj Shanmugam Muthusubramanian Rajaputi Venkatraman Krishnakumar 《Tetrahedron》2011,67(33):6057-6064
A sequential one-pot, atom economical three component reaction yielding medicinally promising ethyl 2-amino-3-cyano-4-(2-ethoxy-2-oxoethyl)-5-oxo-5,6,7,8-tetrahydro-4H-chromene-4-carboxylate derivatives (4a-f) through a tandem Michael addition-cyclization reaction starting with structurally diverse cyclohexane-1,3-dione, diethyl acetylene dicarboxylate, and malononitrile has been carried out in different organic bases under solvent free condition for the optimization of maximum yield. All the formed 4H-chromenes were characterized by spectral and X-ray methods. 相似文献
124.
Gupta D Rajakannu P Shankar B Shanmugam R Hussain F Sarkar B Sathiyendiran M 《Dalton transactions (Cambridge, England : 2003)》2011,40(20):5433-5435
Neutral, stable and luminescent metallacycles decorated with furan units, a 2D rectangle with four furans and a 3D trigonal prism with six furans, were synthesized from readily accessible starting materials through a fac-Re(CO)(3)-directed approach. 相似文献
125.
Polavarapu PL Donahue EA Shanmugam G Scalmani G Hawkins EK Rizzo C Ibnusaud I Thomas G Habel D Sebastian D 《The journal of physical chemistry. A》2011,115(22):5665-5673
Electronic circular dichroism (ECD), optical rotatory dispersion (ORD), and vibrational circular dichroism (VCD) spectra of hibiscus acid dimethyl ester have been measured and analyzed in combination with quantum chemical calculations of corresponding spectra. These results, along with those reported previously for garcinia acid dimethyl ester, reveal that none of these three (ECD, ORD, or VCD) spectroscopic methods, in isolation, can unequivocally establish the absolute configurations of diastereomers. This deficiency is eliminated when a combined spectral analysis of either ECD and VCD or ORD and VCD methods is used. It is also found that the ambiguities in the assignment of absolute configurations of diastereomers may also be overcome when unpolarized vibrational absorption is included in the spectral analysis. 相似文献
126.
Kannan S Mareeswaran P Krishnan M Achiraman S Spencer N Nytingel BF 《Rapid communications in mass spectrometry : RCM》2011,25(2):262-270
Vomeronasal type 2 receptor (V2Rx) from Swiss mouse (Mus musculus (L.)) was analyzed by high-resolution ion-exchange chromatography, reversed-phase high-performance liquid chromatography (RP-HPLC), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), Ion Spray tandem mass spectrometry (MS/MS), 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and 1-aminoanthracene (1-AMA) fluorometric assay. Vomeronasal sensory neuronal cell bound proteins were resolved into major protein peaks. Several proteins were identified and subsequently purified as the V2Rx receptor on 10% SDS-PAGE with trace amounts of other protein bands. The molecular weight of the identified V2Rx was 109 kDa. MALDI-TOF and micro-sequencing experiments demonstrated that the identified V2Rx receptor shared considerable sequence similarity with vomeronasal receptor type 2 (NCBI Accession Number AB267725), which is a seven transmembrane peptide with 912 amino acid residues. The molecular characterization revealed that the N-terminus of the V2Rx receptor contained the 11GAEAAE16 domain involved in pheromone signalling. The biometric assay (octanamine-V2Rx binding) showed the identified V2Rx receptor and mouse sex pheromone to 2-octanamine (methyl heptyl) in a 1:1 ratio. Uptake of odourants determined in physiological condition showed enhanced V2Rx receptors as volatile hydrophobic pheromone receptors in the vomeronasal neuron of the Swiss mouse. 相似文献
127.
Suresh R Muthusubramanian S Senthilkumaran R Manickam G 《The Journal of organic chemistry》2012,77(3):1468-1476
The synthesis of 2-(1H-pyrrolo[2,3-b]pyridin-3-yl)quinolines by a SnCl(2)-catalyzed multicomponent reaction has been described. The reaction proceeds chemo- and regioselectively in an atom-economic way, generating a library of 24 quinoline derivatives. 相似文献
128.
Nagaraj M Boominathan M Perumal D Muthusubramanian S Bhuvanesh N 《The Journal of organic chemistry》2012,77(14):6319-6326
A novel strategy of copper(I)-catalyzed cascade intramolecular nucleophilic attack on N-sulfonylketenimine followed by rearrangement of sulfonimidates to sulfonamides resulting in a library of substituted 8,9-dihydro-5H-imidazo[1,2-a][1,4]diazepin-7(6H)-ones has been developed. 相似文献
129.
130.
The Morita–Baylis–Hillman adducts derived from isatins and maleimides have undergone a facile and efficient allylic nucleophilic substitution reaction with X, S, N, and O-nucleophiles to afford functionalized tetrasubstituted alkene appended oxindoles in very good yield. The MBH adducts and their acetates on treatment with halides, saturated and unsaturated amines, thiols, and trialkyl orthoformates afforded allyl halide, allyl amine, allyl thio-ether and allyl ether derivatives of oxindole, respectively. 相似文献