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1.
研究了对-N,N-二甲氨苯乙烯和蒽乙烯生成的激基缔合物在不同极性溶剂中的荧光特性,发现其荧光发射波长随溶剂的极性增大向长波方向移动,且发现激基缔合物荧光量子产率的大小决定对-N,N-二甲氨苯乙烯和蒽乙烯的光环加成产物的产率。其中反式产物的相对产率随溶液极性增大而降低,并进一步探讨了此光环加成反应的机理。  相似文献   

2.
研究了对-N,N-二甲氨苯乙烯和蒽乙烯生成的激基缔合物在不同极性溶剂中的荧光特性,发现其荧光发射波长随溶剂的极性增大向长波方向移动,且发现激基缔合物荧光量子产率的大小决定对-N,N-二甲氨苯乙烯和蒽乙烯的光环加成产物的产率,其中反式产物的相对产率随溶液极性增大而降低,并进一步探讨了此光环加成反应的机理。  相似文献   

3.
由N,N-二甲氨甲基二茂铁(I)单锂化后与三甲基氯硅烷(Me3SiCl)反应,合成了2-(三甲硅基)二甲氨甲基二茂铁(Ⅱ);Ⅱ再单锂化后与Me3SiCl反应得到了2,5-二(三甲硅基)二甲氨甲基二茂铁(Ⅲ);单锂化的I与Me2SiCl2反是得到了双-(2-(二甲氨甲基)二茂铁基)二甲基硅烷(Ⅳ)双锂化I与二倍量的Me3SiCl反应得到了2,1′-二(三甲硅基)二甲氨甲基二茂铁(V),由碘化(2-(  相似文献   

4.
用一锅法制得了2-三溴甲基-3-甲酰基-4-甲基-5-氧-口恶唑烷酮,它与脯氨酸甲酯及其它氨基酸酯反应生成N-甲基-L-丙氨酰脯氨酸甲酯和系列N-甲基-L-丙氨酰的二肽  相似文献   

5.
张雁  冯小明 《合成化学》1999,7(2):125-127
用一锅法制得了2-三溴甲基-3甲酰基-4甲基-5氧-恶唑烷酮,它与脯氨酸甲酯及其它氨基酸酯反应生成N-甲基-L-丙氨酰脯氨酸甲酯和系列N-甲基-L-丙氨酰的二肽。  相似文献   

6.
本文研究了咪唑以负离子形式负载于氧化铝表面,并进行咪唑的N-烷基化反应,得到八个N-烷基化产物,一般收率在70%以上。研究了不同卤代烃的结构及反应温度对产率的影响。  相似文献   

7.
不同pH值下的D,L-丙氨酰-D,L-丝氨酸及其稀土配合物的^1H,^13CNMR谱,对于该种二肽的不同旋光异构体,有可能对其谱线进行区分和指认。测定了酸解常数和稀土配合物的络合稳定常数。通过分离Ala-Ser的重稀土配合物的接触位移和偶极位移。分析了不同异构体配合物的NMR位移的原因。  相似文献   

8.
锌(Ⅱ)与N-苯甲酰苯丙氨酸及二胺类混配配合物的合成与表征*沈良(杭州师范学院化学系杭州310012)龚钰秋(杭州大学化学系杭州310028)关键词锌(Ⅱ)N-苯甲酰苯丙氨酸二胺混配配合物合成中图分类号O629.7含有末端N-乙酰及N-苯甲酰残基的氨...  相似文献   

9.
研究了不同pH值下的D,L-丙氨酰-D,L-丝氨酸(Ala-Ser)及其稀土配合物的1H、13CNMR谱,对于该种二肽的不同旋光异构体,有可能对其谱线进行区分和指认。测定了酸解常数和稀土配合物的络合稳定常数。通过分离Ala-Ser的重稀土配合物的接触位移和偶极位移。分析了不同异构体配合物的NMR位移的原因。  相似文献   

10.
用纳秒级脉冲辐解动态吸收光谱法研究了Br^-2自由基引发N-(N-二异丙氧基磷酰化甲硫氨酰)色氨酸甲酯的氧化和电子转移过程,结果表明:Br2^-thmhad ad m hi rnudwx N^α-磷酰化二肽中的甲硫氨酸和色氨酸部位。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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