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971.
972.
The successful synthesis of the highly complex model compound ( 2 ) of the CEFGH ring system of schindilactone A ( 1 ) is described. Several synthetic methodologies were developed and applied to achieve this goal, including ring‐closing metathesis (RCM) and Co–thiourea‐catalyzed Pauson–Khand reactions. Furthermore, two independent approaches were developed for the construction of the GH ring of model compound 2 , the key steps of which included Pd–thiourea‐catalyzed carbonylative annulation, methylation, and sequential RCM/oxa‐Michael‐addition reactions. The chemistry developed herein has provided a greater understanding of the synthesis of schindilactone A ( 1 ) and its analogous compounds of the same family.  相似文献   
973.
The coupled cluster method is applied to a strongly correlated lattice Hamiltonian, and the coupled cluster linear response method is extended to the calculation of electronic spectra by finding an approximation to a resolvent operator which describes the spectral response of the coupled cluster solution to excitation operators. In this spectral coupled cluster method, the ground and excited states appear as resonances in the spectra, and the resolvent can be iteratively improved in selected spectral regions. The method is applied to a MnO2 plane model which corresponds to previous experimental works.  相似文献   
974.
975.
The Hiyama cross‐coupling reaction is a powerful method for carbon–carbon bond formation. To date, the substrate scope of this reaction has predominantly been limited to sp2–sp2 coupling reactions. Herein, the palladium‐catalysed Hiyama type cross‐coupling of vinyldisiloxanes with benzylic and allylic bromides, chlorides, tosylates and mesylates is reported. A wide variety of functional groups were tolerated, and the synthetic utility of the methodology was exemplified through the efficient total synthesis of the cytotoxic natural product bussealin A. In addition, the antiproliferative ability of bussealin A was evaluated in two cancer‐cell lines.  相似文献   
976.
977.
978.
In this work, we have demonstrated a family of diamondoid metal–organic frameworks (MOFs) based on functionalized molecular building blocks and length‐adjustable organic linkers by using a stepwise synthesis strategy. We have successfully achieved not only “design” and “control” to synthesize MOFs, but also the functionalization of both secondary building units (SBUs) and organic linkers in the same MOF for the first time. Furthermore, the results of N2 and H2 adsorption show that their surface areas and hydrogen uptake capacities are determined by the most optimal combination of functional groups from SBUs and organic linkers, interpenetration, and free volume in this system. A member of this series, DMOF‐6 exhibits the highest surface area and H2 adsorption capacity among this family of MOFs.  相似文献   
979.
980.
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