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51.
The first total synthesis of (+)-1S-minwanenone, an archetypical seco-prezizaane sesquiterpene, has been accomplished from a readily available chiral endo-tricyclic synthon following a flexible strategy. 相似文献
52.
In an approach towards the enantioselective total synthesis of the novel bioactive natural product Sch 642305, an unusual diastereoselection during the key RCM reaction, resulted in the synthesis of the 11-epi-isomer of Sch 642305. 相似文献
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Enantiomerically pure (3S,7R,8aS)-3-phenyloctahydropyrrolo[1,2-a]pyrazine-7-ol, (3S,7R,8aS)-3-methyl octahydropyrrolo[1,2-a]pyrazine-7-ol, (3S,7R,8aS)-3-isopropyloctahydropyrrolo[1,2-a]pyrazine-7-ol and (3S,7R,8aS)-3-isobutyloctahydropyrrolo[1,2-a]pyrazine-7-ol 16d were synthesized via preparation of the corresponding cyclic amides from enantiomerically pure l-proline and hydroxyproline derivatives followed by reduction using sodium borohydride-iodine. 相似文献
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This paper reports the experimental results of parametric amplification applied to a harmonically forced MEMS gyroscope. Parametric amplification of the forced response at resonance in the range 10–100 is investigated. Several important factors pertinent to practical exploitation are highlighted. The main obstacle to high gain parametric amplification is the nonlinearity of the electrostatic force which becomes significant for high amplitude vibration. By significantly reducing the harmonic forcing level to just above the noise threshold, parametric amplification of the resonant response by a factor of 80 has been achieved whilst maintaining linear response characteristics. 相似文献
58.
K.R. Venugopala Reddy M.N.K. Harish M.H. Moinuddin Khan 《Journal of fluorine chemistry》2007,128(9):1019-1025
This publication discuss the synthesis and characterization of pure 1,3,8,10,15,17,22,24-octafluorophthalocyanines of copper(II), cobalt(II), nickel(II) and zinc(II). The complexes are characterized by elemental analysis, electronic spectra, IR spectra, thermal studies and X-ray powder diffraction method to check the purity and integrity of the complexes. The magnetic measurements over the range of magnetic field strength 1.03-2.32 kG showed a variation of magnetic moments with field strength indicating the presence of intermolecular co-operative effect. 相似文献
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Jani D. B. Bhabhor Kiran Dadi Mohsin Doshi Sachindra Jotaniya P. V. Ravat Harish Bhatt Kumar 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2011-2031
Journal of Thermal Analysis and Calorimetry - Solid desiccant-assisted cooling and dehumidification systems are becoming very popular nowadays for maintaining the required thermal comfort in... 相似文献
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