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91.
Benzocycloheptapyrimidines are an important class of compounds because of their pharmacological properties. We report here two new synthetic procedures for the preparation of 2,4-dialkylamino substituted benzocycloheptapyrimidines. One of these methods is based on the reaction of substituted cyanamides with the vinyl triflate of the 1-benzosuberone while the other preparation relies on the nucleophilic displacement of methylsulfonyl groups by secondary amines at the 2 and 4 positions of benzocycloheptapyrimidine intermediates. 相似文献
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We prove that amenable and reflexive operator algebras are semisimple and are finite direct sums of simple Banach algebras of operators. 相似文献
95.
AbstractWe study the transfer via functors between abelian categories of the (dual) relative splitness of objects with respect to a fully invariant short exact sequence. We mainly consider fully faithful functors and adjoint pairs of functors. We deduce applications to Grothendieck categories, (graded) module categories and comodule categories. 相似文献
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A simple and efficient synthesis of steroidal hybrids of estrogen and vitamin D3 through modification of estrone (5) at position 16 of the steroid nucleus is described. 相似文献
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Abraham F. Jalbout Xin‐Hua Li Hakima Abou‐Rachid 《International journal of quantum chemistry》2007,107(3):522-539
The molecular spectroscopic constants for the chalcogenide complexes MX (M?Ge, Sn, Pb; X?O, S, Se, Te, Po) and their corresponding MX? anions are presented with the LSDA/SDD, B1LYP/SDD, and B3LYP/SDD methods. Although many methods were attempted, only the most promising results are reported. We show that the best results are obtained by LSDA/SDD calculations, and thus this method is emphasized as an illustrative example of our methodology. The potential energy curves and physical property characterizations for X1 ∑+ state of LuH and LuF are presented with a variety of density functional theory (DFT) methods. Comparisons with wave function‐based treatments (HF, MP2, CCSD, QCISD) are made in addition to experimental correlations. We show that the best results are obtained by the B3LYP/SDD method for LuH, and the MPW1PW91/SDD method for LuF. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献