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排序方式: 共有621条查询结果,搜索用时 15 毫秒
611.
Flow chemistry approach for partial deuteration of alkynes: synthesis of deuterated taxol side chain
S. Chandrasekhar B.V.D. VijaykumarB. Mahesh Chandra Ch. Raji ReddyP. Naresh 《Tetrahedron letters》2011,52(30):3865-3867
The partial deuteration of alkynes proceeds via a flow chemistry approach under Lindlar’s heterogeneous catalysis to provide cis-dideuterated olefins in good yields. Further, dideuterated olefin has been successfully utilized for Sharpless asymmetric dihydroxylation followed by Mitsunobu reaction for the synthesis of deuterated taxol side chain. 相似文献
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Katharigatta N. Venugopala Pottathil Shinu Christophe Tratrat Pran Kishore Deb Raquel M. Gleiser Sandeep Chandrashekharappa Deepak Chopra Mahesh Attimarad Anroop B. Nair Nagaraja Sreeharsha Fawzi M. Mahomoodally Michelyne Haroun Mahmoud Kandeel Syed Mohammed Basheeruddin Asdaq Viresh Mohanlall Nizar A. Al-Shari Mohamed A. Morsy 《Molecules (Basel, Switzerland)》2022,27(9)
Alteration of insect growth regulators by the action of inhibitors is becoming an attractive strategy to combat disease-transmitting insects. In the present study, we investigated the larvicidal effect of 1,2,3-triazolyl-pyrimidinone derivatives against the larvae of the mosquito Anopheles arabiensis, a vector of malaria. All compounds demonstrated insecticidal activity against mosquito larvae in a dose-dependent fashion. A preliminary study of the structure–activity relationship indicated that the electron-withdrawing substituent in the para position of the 4-phenyl-pyrimidinone moiety enhanced the molecules’ potency. A docking study of these derivatives revealed favorable binding affinity for the sterol carrier protein-2 receptor, a protein present in the intestine of the mosquito larvae. Being effective insecticides against the malaria-transmitting Anopheles arabiensis, 1,2,3-triazole-based pyrimidinones represent a starting point to develop novel inhibitors of insect growth regulators. 相似文献
614.
P. Raghunatha Mohammed Naseeruddin Inamdar Syed Mohammed Basheeruddin Asdaq Mansour Almuqbil Abdullah R. Alzahrani Saleh I. Alaqel Mehnaz Kamal Firas Hamdan Alsubaie Walaa F. Alsanie Abdulhakeem S. Alamri Syed Imam Rabbani Mahesh Attimarad S. Mohan Majid Alhomrani 《Molecules (Basel, Switzerland)》2022,27(19)
Cardiovascular diseases are one of the major causes of mortalities worldwide. In the present research, new synthetic derivatives of thiazole were studied using isolated hearts and blood vessels of rats. The heart and thoracic aorta were tested with six new synthesized thiazole acetic acid derivatives (SMVA-10, SMVA-35, SMVA-40, SMVA-41, SMVA-42 and SMVA-60), and the data obtained were statistically analyzed and compared. Isolated rat hearts were used to record the changes in developed tension and heart rate, while thoracic aortas were used to measure the contractile response, before and after treatments. Analysis of the results indicated a significant (p < 0.01) increase in developed tension with the addition of SMVA-35, SMVA-40, SMVA-41 and SMVA-42, which was augmented in the presence of adrenaline without affecting the heart rate. On the other hand, acetylcholine significantly decreased the developed tension, which was significantly reversed (p < 0.01) in the presence of compounds (SMVA-35 and SMVA-60). However, in the presence of SMVA-35 and SMVA-40, acetylcholine-induced bradycardia was significantly (p < 0.01) reduced. Furthermore, only SMVA-42 induced a dose-dependent contractile response in the isolated blood vessel, which was abolished in the presence of prazosin. Therefore, it can be concluded that some of the new synthesized thiazole derivatives exhibited promising results by raising the developed tension without changing the heart rate or blood vessel function, which could be helpful in failing heart conditions. However, more research is required to fully comprehend the function, mechanism and effectiveness of the compounds. 相似文献
615.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
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Prof. Mahesh K. Lakshman 《Chemical record (New York, N.Y.)》2023,23(1):e202200182
Several naturally occurring purine and pyrimidine nucleosides contain an amide linkage as part of the heterocyclic aglycone. Enolization of the amide and conversion to leaving groups at the amide carbon atom permits base modification by addition-elimination types of processes. Although a number of methods have been developed over the years for accomplishing such conversions, the present Personal Account describes efforts from the Lakshman laboratories. Facile activation of the amido groups in nucleobases can be achieved with peptide-coupling agents. Subsequent reaction with nucleophiles then accomplishes the base modifications. In many cases, the activation and displacement steps can be done as two-step, one-pot processes, whereas in other cases, discrete storable activated nucleosides can be isolated for subsequent displacement reactions. Using such an approach a wide range of nucleoside base modifications is readily achievable. In many instances, mechanistic investigations have been conducted so as to understand the activation process. 相似文献
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