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981.
Sridevi Gorle Suresh Maddila Santosh Chokkakula Palakondu Lavanya Moganavelli Singh Sreekanth B. Jonnalagadda 《Journal of heterocyclic chemistry》2016,53(6):1852-1858
A new series of 5‐fluoro‐N4‐(3‐(4‐substitutedbenzylamino)phenyl)‐N2‐(4‐morpholinophenyl)pyrimidine‐2,4‐diamine derivatives ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j ) are prepared from using an intermediate compound 5‐fluoro‐N4‐(3‐(aminophenyl)‐N2‐(4‐morpholinophenyl)pyrimidine‐2,4‐diamine ( 5 ). The structures of the newly synthesized products are established from their spectral 1H‐NMR, 13C‐NMR, 19F‐NMR, ESI‐MS, and analytical data. Here we report the synthesized compounds and larvicidal activity. All the compounds are screened for their significant larvicidal activity against third instar larvae at 24, 48, and 78‐h time exposure, and values were compared with standard drug Malathion. The Compounds 7i , 7a , 7c , 7f , and 7j exhibited significant activity. However the compounds 7b , 7e , 7d , and 7h showed excellent activity when compared to the above compounds and to standard drug malathion too because of the presence of mild electron withdrawing groups such as trifluoro, fluorine, hydroxy, nitro, and methoxy derivatives which are attached to the benzyl ring. 相似文献
982.
AbdulKarim-Talaq Mohammad H. T Srinivasa HariPrasad Suresh Guan-Yeow Yeap 《Liquid crystals》2016,43(12):1739-1747
The synthesis and characterisation of three sets of symmetric dimeric compounds composed of seven-membered oxazepinedione heterocyclic rings were carried out. All the dimers possess the tetradecyl- (n = 14) alkyl side chain attached to the nitrogen atom of the oxazepinedione core. The oxazepinedione core in turn was connected with varied connecting spacers (n = 4, 6, 8, 10 and 12). The dimers were spectroscopically characterised by FT-IR, 1H-NMR, 13C-NMR and elemental analysis techniques. The compounds were investigated for liquid crystalline properties using differential scanning calorimetry and polarising optical microscopy with heating assembly. The precursor imines 2a–e itself started exhibiting liquid crystalline SmA/tilted hexatic mesophase. Further fusion of 2a–e with maleic anhydride, succinic anhydride and phthalic anhydride gave the novel oxazepinedione-derived symmetric dimers 3a–e, 4a–e and 5a–e respectively. The dimers 3a–e and 4a–e did not exhibit any liquid crystal (LC) properties. However, the phthalic anhydride-fused oxazepinediones 5a–e show monotropic nematic liquid crystalline phase. The results indicate that the formation of mesophase is dependent on the type of fused oxazepinedione ring. 相似文献
983.
Synthesis of Novel Drug‐Like Small Molecules Based on Quinoxaline Containing Amino Substitution at C‐2
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K. Raghavendra Rao Akula Raghunadh Ramamohan Mekala Suresh Babu Meruva K. Ravi Ganesh T. Krishna Dipak Kalita Eppakayala Laxminarayana Manojit Pal 《Journal of heterocyclic chemistry》2016,53(3):901-908
A series of novel “drug‐like” small molecules based on quinoxaline containing amino substitution at C‐2 were synthesized. All these molecules were prepared either via the reaction of 2‐phenyl‐3‐(piperazin‐1‐yl)quinoxaline with acyl bromides or benzyl bromides or various carboxylic acids or via the reaction of 2‐chloro‐3‐phenylquinoxaline with various amines. The structures of these novel compounds were confirmed by spectral analysis. The strategy used is simple and efficient and afforded good yields of quinoxaline derivatives. 相似文献
984.
985.
986.
Vibha Gautam Veera Babu KagitaSudhir Nambiar Gutala PhaneendraSulur G. Manjunatha Sridharan RamasubramanianM. Suresh Babu Jaikumar KeshwanSagar Bhagat Ravindran PrakashRamachandra Puranik 《Tetrahedron letters》2014
A simple synthetic approach has been developed towards one pot synthesis of 2-imidazolines under mild acidic conditions from N-acetyl glucosamine via reductive amination followed by dehydrative cyclization. Synthetic studies were explored in detail with different amines and sugar derivatives. While the conversion was good, the corresponding substituted imidazolines were obtained in moderate yields. 相似文献
987.
Santanu Chand Gaurav Verma Arun Pal Shyam Chand Pal Prof. Shengqian Ma Dr. Madhab C. Das 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(46):11804-11810
Accumulation of high concentrations of Al(III) in body has a direct impact on health and therefore, the trace detection of Al(III) has been a matter for substantial concern. An anionic metal organic framework ({[Me2NH2]0.5[Co(DATRz)0.5(NH2BDC)] ⋅ xG}n; 1 ; HDATRz=3,5-diamino-1,2,4-triazole, H2NH2-BDC=2-amino-1,4-benzenedicarboxylic acid, G=guest molecule) composed of two types of secondary building units (SBU) and channels of varying sizes was synthesized by employing a rational design mixed ligand synthesis approach. Free −NH2 groups on both the ligands are immobilized onto the pore surface of the MOF which acts as a superior luminescent sensor for turn-on Al(III) detection. Furthermore, the large channels could allow the counter-ions to pass through and get exchanged to selectively detect Al(III) in presence of other seventeen metal ions with magnificent luminescence enhancement. The observed limit of detection is as low as 17.5 ppb, which is the lowest among the MOF-based sensors achieved so far. To make this detection approach simple, portable and economic, we demonstrate MOF filter paper test for real time naked eye observation. 相似文献
988.
Dongre Sandeep Kumar Sunil Suresh S. Rangaswamy D. R. Sannappa J. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(7):2825-2847
Journal of Radioanalytical and Nuclear Chemistry - The estimated mean value of activity of radionuclides (226Ra, 232Th, and 40K) in the forest environment of Shankaraghatta are... 相似文献
989.
Chinnakurli Dwarakanath Shruthi Gurukar Shivappa Suresh 《Russian Journal of Electrochemistry》2021,57(4):380-387
Russian Journal of Electrochemistry - A trustworthy and simple electrode is fabricated using palladium nanoribbons for the determination of hemoglobin. Palladium nanoparticles were synthesised from... 相似文献
990.