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71.
M.V. Madhubabu R. Shankar T. Krishna Y. Satish Kumar Y. Chiranjeevi Ch. Muralikrishna H. Rama Mohan Satish S. More M.V. Basaveswara Rao Raghunadh Akula 《Tetrahedron: Asymmetry》2017,28(12):1803-1807
A convergent approach towards the synthesis of the 2-alkyl-substituted tetrahydroquinoline alkaloid (?)-cuspareine via enantiospecific construction of the (R)-benzyl 2-formyl-3,4-dihydroquinoline-1(2H)-carboxylate. We have achieved an efficient enantiospecific synthesis of (?)-cuspareine starting from known key starting materials. The reactions employed for individual transformations are simple and high yielding, and the strategy could potentially be easily extended. 相似文献
72.
Metal quinolates, Liq Alq3 Znq2 Mgq2 exhibit efficient luminescence in blue green region and find applications as emission layer in OLEDs. In most of these quinolates the excitation spectra are broad in the range 350 to 410 nm, just short of emission spectra of efficient GaN based blue LEDs. In this paper we report metal quinolates synthesized by slightly modified method in which the excitation gets extended beyond 450 nm so that there is better overlap between emission spectra of blue LED and the excitation spectra. Therefore these phosphors may be used for PC-LED applications. 相似文献
73.
74.
Ravindra Mahadev Patil Anil A. Ghanwat Satyanarayana Ganugapati 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):114-123
Well-defined four-arm star poly(?-caprolactone)-block-poly(cyclic carbonate methacrylate) (PCL-b-PCCMA) copolymers were synthesized by combining ring-opening polymerization (ROP) with atom transfer radical polymerization (ATRP). First, a four-arm poly(?-caprolactone) (PCL) macroinitiator [(PCL-Br)4] was prepared by the ROP of ?-CL catalyzed by stannous octoate at 110°C in the presence of pentaerythritol as the tetrafunctional initiator followed by esterification with 2-bromoisobutyryl bromide. The sequential ATRP of CCMA monomer was carried out by using the (PCL-Br)4 tetrafunctional macroinitiator (MI) and in the presence of CuBr/2, 2′-bipyridyl system in DMF at 80°C with [(MI)]:[CuBr]:[bipyridyl] = 1:1:3 to yield block polymers with controlled molecular weights (Mn (NMR) = 10700 to 27300 g/mol) by varying block lengths and with moderately narrow polydispersities (Mw/Mn = 1.2–1.4). Block copolymers with different PCL: PCCMA copolymer composition such as 50:50, 70:30 and 74:26 were prepared with good yields (48-74%). All these block copolymers were well characterized by NMR, FTIR and GPC and tested their thermal properties by DSC and TGA. 相似文献
75.
76.
Rupali L. Magar Prashant B. Thorat Pratima B. Thorat Vinod V. Thorat Bhagawan R. Patil Rajendra P. Pawar 《中国化学快报》2013,24(12):1070-1074
The Biginelli-type compounds 4,5,8a-triarylhexahydropyrimido[4,5-d]pyrimidine-2,7(1H,3H)-diones were synthesized by a one-pot three-component reaction using sulfated tin oxide as a reusable catalyst. This method has the advantages of high yields, short reaction time, simple starting materials and reusability of catalyst for several times. 相似文献
77.
An efficient stereoselective three-component reaction for the synthesis of functionalized spiro[4H-pyran-3,3′-oxindole] derivatives was realized through an organocatalyzed domino Knoevenagel/Michael/cyclization reaction using a cinchonidine-derived thiourea as the catalyst. Using water as the additive was found to improve the product ee values significantly. Under the optimized conditions, the reactions between isatins, malononitrile, and 1,3-dicarbonyl compounds yield the desired spirooxindole products in good yields (71–92%) and moderate to high ee values (up to 87% ee). 相似文献
78.
3′O-silylated derivatives of 5′-O-DMT-2′deoxynucleoside (2) were synthesized in high yield by reaction of 5′-O-DMT-2′-deoxynucleosides (1) with tert-butyl dimethylsilylchloride using sodium hydride, benzyltriethylammonlum chloride [TEBA] and a catalytic amount of dibenzo-[18]-crown-6 [DB-18-C-6] or 15-crown-5 [15-C-51 under mild reaction conditions. 相似文献
79.
Sachin S. Patil 《合成通讯》2013,43(2):206-212
2-Substituted benzoxazole and benzothiazole were synthesized from condensation of aldehyde and 2-aminophenol or 2-aminothiophenol via a one-pot process using diethyl bromo phoshonate and tert-butyl hypochlorite. 相似文献
80.
P. V. Badadhe L. R. Patil S. S. Bhagat A. V. Chate D. W. Shinde M. D. Nikam C. H. Gill 《Journal of heterocyclic chemistry》2013,50(5):999-1004
The title compounds 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h and 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h have been synthesized from β‐diketones and chromones, respectively, having 5‐methyl‐3‐phenylisoxazole moiety. Substituted 2‐acetylphenyl 5‐methyl‐3‐phenylisoxazole‐4‐carboxylate 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h were converted into 1‐(2‐hydroxyphenyl)‐3‐(5‐methyl‐3‐phenylisoxazole‐4‐yl)propane‐1,3‐dione 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h by Baker–Venketaraman transformation. Further, the cyclodehydration of diketone 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h with glacial acetic acid in conc. HCl at reflux gave corresponding substituted 2‐(5‐methyl‐3‐phenylisoxazole‐4‐yl)‐4H‐chromen‐4‐one 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h . The corresponding 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h react with hydrazine hydrate in presence of glacial acetic acid in ethanol at reflux to furnish 2‐(5‐5(5‐methyl‐3‐phenylisoxazole‐4‐yl)‐1H‐pyrazole‐3‐yl)phenol 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h . The structures of all newly synthesized compounds have been confirmed by IR, 1H NMR, mass spectral data, as well as elemental analysis. The synthesized compounds have been screened for their antimicrobial activity. Some of the compounds show better antimicrobial activity as compared with the reference drugs Streptomycin, Ampicillin, Gentamycin, Cefixime, and Ketoconazole. 相似文献