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排序方式: 共有31条查询结果,搜索用时 31 毫秒
1.
An efficient method for the synthesis of benzo[b]benzofurano[2,3-e][1,6]naphthyridine-8-one derivatives has been developed via Pictet-Spengler reaction of 4-(3-aminobenzofuran-2-yl)quinoline-2-ones,which could be obtained from alkylation of 4-bromomethylquinoline-2-ones with salicylonitrile and subsequent Thorpe-Ziegier isomerization,with aromatic aldehydes under p-TsOH as catalyst in good yields.  相似文献   
2.
An efficient method for the synthesis of novel benzo[b]pyrido[3',2':4,5] thieno[2,3-e][1,6] naphthyridine-8-one derivatives has been developed using a Pictet-Spengler reaction between 4-(3-aminothieno[2,3-b]pyridin-2-yl)quinoline-2-ones, which could be obtained from the alkylation of 4-bromomethylquinoline-2-ones with 3-cyanopyridine-2-thione followed by a Thorpe-Ziegler isomerization, and aromatic aldehydes under p-TsOH as catalysis in good yields.  相似文献   
3.
By using the extended double complex function method, the statically axisymmetric self-dualSU(2) gauge field equations and, in turn, the Belinsky-Zakharov solution-generating technique are generalized to extended double forms. The restriction on “soliton index” in the original solution-generating technique is eliminated so that for each positive integer, we can obtainphysical soliton solutions of the statically axisymmetric self-dualSU(2) gauge field equations in pairs. Some sufficient conditions are given for seed solutions with which the corresponding scattering wave function can be written out directly. As examples, some soliton solution families are given, most solutions of which are new.  相似文献   
4.
1-(2-苯并呋喃酰基)愈创兰烃薁的合成   总被引:1,自引:0,他引:1  
王道林  韩珊  谷峥  徐姣 《有机化学》2008,28(9):1641-1645
在路易斯酸作用下, 以氯乙酰氯为酰基化试剂, 对愈创兰烃薁进行了酰化反应研究, 将氯乙酰化产物与水杨醛在温和反应条件下进行缩合, 以较好的收率、高选择性地得到1-(2-苯并[b]呋喃酰基)兰烃薁类衍生物, 其结构经1H NMR, IR及元素分析等得以证实.  相似文献   
5.
新型薁类-1-酰腙化合物的合成及抗菌活性研究   总被引:1,自引:0,他引:1  
王道林  徐姣  韩珊  谷峥 《有机化学》2008,28(11):2016-2019
为了合成和研究具有薁类结构物质的新的生物活性, 以1-薁类羧酸甲酯为起始原料, 经过酰肼化、与芳香醛及酮类化合物的缩合, 合成了含有酰腙类结构的薁类衍生物, 其结构经1H NMR, IR和元素分析确证. 对所得化合物进行了抗菌活性测试, 初步表明它们具有一定的活性.  相似文献   
6.
A so-called extended elliptical-complex (EEC) function method is proposed and used to further study the Einstein–Maxwell-dilaton-axion theory with p vector fields (EMDA-p theory, for brevity) for . An Ernst-like matrix EEC potential is introduced and the motion equations of the stationary axisymmetric EMDA-p theory are written as a so-called Hauser–Ernst-like self-dual relation for the EEC matrix potential. In particular, for the EMDA-2 theory, two Hauser–Ernst-type EEC linear systems are established and based on their solutions some new parametrized symmetry transformations are explicitly constructed. These hidden symmetries are verified to constitute an infinite-dimensional Lie algebra, which is the semidirect product of the Kac–Moody algebra and Virasoro algebra (without centre charges). These results show that the studied EMDA-p theories possess very rich symmetry structures and the EEC function method is necessary and effective.  相似文献   
7.
The braided differential bialgebras on braided matrix algebras (with bothmultiplicative and additive coproducts) and on quantum hyperplanes (withadditive coproduct) are proven to be covariant under the braided coactions ofthe quantized braided groups, which contain the usual quantum group-covarianceas a special case. This means that the above braided differential bialgebras havemore and richer symmetries. It is also shown that the braided matrix algebraitself and the related braided differential algebra constitute two braided rings withthe two above-mentioned coproducts.  相似文献   
8.
An efficient method for the synthesis of novel benzo[b]pyrimido[4',5':5,4]thieno[2,3e]-[1,6]naphthyridine-8-one derivatives via Pictet–Spengler cyclization is reported. The reaction of 4-(3-aminopyrimido[4,5-d]thieno-2-yl)quinoline-2-ones, which could be obtained from Thorpe–Ziegler isomerization of 4-bromomethylquinoline-2-ones and 5-cyano-1,6-dihydro-4-methyl-2-phenyl-6-thioxopyrimidine,with aromatic aldehydes in the presence of BF_3·OEt_2 gives pyrimidothieno[1,6]naphthyridines in good yields.  相似文献   
9.
Nagatomo's universal Grassmann manifold scheme is extended to a double form, which is used to find the exact solutions of the stationary axisymmetric vacuum gravitational field equations. Some new results are given.  相似文献   
10.
The double-complex function method is used to find a multiple Lax pair for the double Ernst equation. Then multiple hidden symmetries and multiple infinite sequences of nonlocal conserved charges are obtained. The result of Papachristou and Harrison is contained in our result.  相似文献   
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