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941.
B.V. Subba Reddy P. Sivaramakrishna Reddy B. Phaneendra Reddy J.S. Yadav Ahamad Al Khazim Al Ghamdi 《Tetrahedron letters》2013
A stereoselective total synthesis of xyolide is described employing MacMillan α-hydroxylation, Steglich esterification, and ring closing metathesis as key steps. The use of organocatalytic MacMillan α-hydroxylation to construct two of the chiral centers of the xyolide makes this approach attractive. 相似文献
942.
Thummalapally Srikanth Reddy Dorigondla Kumar Reddy Manchala Narasimhulu Dasari Ramesh Yenamandra Venkateswarlu 《Helvetica chimica acta》2010,93(11):2158-2163
Total synthesis of mevinic acid analog 1 has been achieved efficiently starting from chiral 2,3‐O‐isopropylidene‐D ‐glyceraldehyde ( 2 ). The synthesis involves Mitsunobu reaction and Evans' intramolecular oxa‐Michael syn‐addition reactions as key steps. 相似文献
943.
Oxidation of nitrogen-containing heteroaryl-2-methanols to esters with Ag2O and isopropyl iodide is reported. This methodology is very mild and can tolerate many functional groups. 相似文献
944.
Ivan E. Dimitrov Ravinder Reddy John S. Leigh 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2000,145(2):302
Intermolecular 129Xe–1H nuclear Overhauser effects and 129Xe longitudinal relaxation time measurements were used to demonstrate that the dipole–dipole coupling is the dominant relaxation mechanism for 129Xe in water, at room temperature. 129Xe–1H cross-relaxation rates were derived to be ςXeH 3.2 ± 0.3 × 10−3 s−1, independent of xenon pressure (in the range of 1–10 bar) and of the presence of oxygen. Corresponding xenon–proton internuclear distances were calculated to be 2.69 ± 0.12 Å. Using the magnitude of the dipole–dipole coupling and the spin density ratio between dissolved xenon and bulk water, it is estimated that 129Xe–1H spin polarization-induced nuclear Overhauser effects would yield little net proton signal enhancement in water. 相似文献
945.
946.
An inexpensive and safer reagent system comprising of PMHS and ZnCl2 has been developed for the selective reduction of carbonyl compounds to corresponding alcohols. 相似文献
947.
Synthesis and Spectral Characterization of Related Substances of Lacidipine,an Antihypertensive Drug
V. V. N. K. V. Prasada Raju Ganta Madhusudhan Reddy Vedantham Ravindra Vijayavitthal T. Mathad P. K. Dubey 《合成通讯》2013,43(12):2137-2145
Five related substances (impurities) were detected in lacidipine bulk drug substance by a simple high-performance liquid chromatographic method (HPLC) and were identified by liquid chromatography–mass spectrometry (LC-MS). These related substances were independently synthesized, characterized, and co-injected with the sample containing impurities. 相似文献
948.
949.
The synthesis of macrolides1 is currently under intensive investigations because of their diverse biological and physiological activities. The recent developments in their synthetic strategies made the task easier for synthesis of several naturally occurring rnacrolides. 相似文献
950.
The synthesis, characterisation and antifeedant activity of some new angular dicoumarins prepared from 2,4-diacetyl resorcinol has been reported. 相似文献