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1.
2-Amino-4-(2-hydroxynaphthyl)-4H-chromene-3-carbonitriles were synthesized by Michael addition of various 3-cyanoiminocoumarins and β-naphthol in good yield. The heterocyclization of these materials in an acidic medium leads new heterocyclic compounds, which have not previously been described, in moderate to good yields and good selectivity. The synthesized compounds were characterized by infrared, 1H NMR, 13C NMR, two-dimensional NMR, and elemental analysis. 相似文献
2.
Jun Min HUANG* Hui CHEN Ru Yu CHEN Institute of Elemento-Organic Chemistry National Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 《中国化学快报》2002,(2)
Organophosphorus compounds are ubiquitous in nature and they have broad applications in the fields of agriculture and medicine1-4. There has been a considerably growing interest in heterocyclic compounds due to their pharmaceutical importance and extensive application in organic synthesis, and the application of heterocycles is suggested to enhance the biological activity and/or offer other diverse properties5-7. In the previous work8, we have reported that 11-ethoxycarbonylmethyl-6-oxo-3, 4… 相似文献
3.
1 INTRODUCTION In recent years, chiral β-amino alcohols have attracted much attention due to their special bio- logical functions and catalytic activities. Chiral β- amino alcohol moieties are usually found not only in natural products (e.g., cinchona alkaloids, ephe- drine, toxal, etc.) with special biological activities[1, 2], but also critical structural segments of some syn- thesized biologically active compounds, such as adrenergic agonists or antagolist[3, 4] and inhibitors for HI… 相似文献
4.
1 INTRODUCTION Triarylamines constitute a well known class of hole conducting material[1~4]. On the other hand , oxadiazole-based compounds as good electron- transporting materials[5,6] have played an important role in the fabrication of multiple-layer light- emitting diode devices. It is well known that, to achieve good performance in electroluminescence (EL) devices, the injection of electron and hole should be in balance[7]. The requirement might be met in a new compound containing … 相似文献
5.
1INTRODUCTIONOwingtotheirwideoccurenceinavarietyofbiologicalyactivenaturalproductsandtheirutilityasvaluablesyntheticintermedi... 相似文献
6.
Indanones 3 were prepared from the reaction of indanone (1) with corresponding benzaldehyde derivatives 2, as described in the literature. Then, indenones 3 were subjected to KOtBu-catalyzed Michael addition with malononitrile to give a mixture of diastereomers 5 with a low conversion and no diastereoselection. Utilization of phase-transfer catalyst such as benzyltriethylammonium chloride or N-benzylcinchonidinium chloride had a positive effect on both conversion and diastereoselection. The structure of diastereomers 5 was determined by spectroscopic methods (NMR, IR). 相似文献
7.
建立了受阻胺光稳定剂3-(2,2,6,6-四甲基哌啶-4-氨基)丙酸十二酯的合成工艺.以2,2,6,6-四甲基-4-哌啶胺、丙烯酸甲酯为原料,经M ichael加成,生成的3-(2,2,6,6-四甲基哌啶-4-氨基)丙酸甲酯再与十二醇进行酯交换反应制得.并对所涉及的酯交换反应的工艺参数进行了优化.实验结果表明,四异丙基钛酸酯催化剂的催化效果最好;在3-(2,2,6,6-四甲基哌啶-4-氨基)丙酸甲酯与十二醇的摩尔比为1∶1.10,四异丙基钛酸酯催化剂的用量为反应物总质量的0.30%,反应温度180℃,反应时间8 h的条件下,酯交换反应收率为90.6%.该工艺总收率为86.3%.目标产物及中间体的结构通过MS进行了表征. 相似文献
8.
Synthesis and Crystal Structure of 9-[3-Oxo-1-(4-bromopheny)-3-phenypropyl] fluorine 总被引:1,自引:0,他引:1
A novel compound of 9-[3-oxo-1-(4-bromopheny)-3-phenypropyl]fluorine (3) was synthesized via nucleophilic addition reaction under solvent-free condition. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of triclinic system, space group P-1 with a=9.7919(16), b=11.0932(18), c=11.2534(19) , α=76.927(3), β=67.452(3), γ=84.895(3)°, V=1099.7(3) 3, Z=2, Dc=1.369 g/cm3, μ=1.886 mm-1, F(000)=464, R=0.0586 and wR=0.1562 for 3145 observed reflections with Ⅰ 2σ(Ⅰ). π-π Stacking interactions contribute to the stability of the structure. 相似文献
9.
We report the first synthetic route to prepare 3-methyl-4-nitro-5-(2-alkylethenyl)isoxazoles in high yields and exclusively as E-diastereoisomers. 相似文献
10.
DongMeiCAI MinJieLI DaLiangLI TianPaYOU 《中国化学快报》2004,15(2):163-166
Novel C-nucleosides of tiazofurin analogue (2-[2-(hydroxymethyl)-1,3-dioxolan-5-yl] 1,3-thiazole-4-carboxamide) and its thiol-substituted derivative (2-[2-(mercaptomethyl)-1,3-dioxolan-5-yl] 1, 3-thiazole-4-carboxamide) were synthesized from methyl acrylate through a multistep procedure. Their structures were confirmed by IR, ^1HNMR, ^13CNMR and elemental analysis. 相似文献
11.
Several biological effects of chalcones have been reported to be associated with their thiol reactivity. In vivo, the reactions can result in the formation of small-molecule or protein thiol adducts. Both types of reactions can play a role in the biological effects of this class of compounds. Progress of the reaction of 4-methyl- and 4-methoxychalcone with glutathione and N-acetylcysteine was studied by the HPLC-UV-VIS method. The reactions were conducted under three different pH conditions. HPLC-MS measurements confirmed the structure of the formed adducts. The chalcones reacted with both thiols under all incubation conditions. The initial rate and composition of the equilibrium mixtures depended on the ratio of the deprotonated form of the thiols. In the reaction of 4-methoxychalcone with N-acetylcysteine under strongly basic conditions, transformation of the kinetic adduct into the thermodynamically more stable one was observed. Addition of S-protonated N-acetylcysteine onto the polar double bonds of the chalcones showed different degrees of diastereoselectivity. Both chalcones showed a Michael-type addition reaction with the ionized and non-ionized forms of the investigated thiols. The initial reactivity of the chalcones and the equilibrium composition of the incubates showed a positive correlation with the degree of ionization of the thiols. Conversions showed systematic differences under each set of conditions. The observed differences can hint at the difference in reported biological actions of 4-methyl- and 4-methoxy-substituted chalcones. 相似文献
12.
A thermally stable dioxetane bearing a 3-(1-cyanoethenyl)phenyl group (1) was synthesized. Michael addition of an anion of malonate (3a,b) to a dioxetane (1) substituted with a 3-(1-cyanoethenyl)phenyl moiety took place to give an intermediary dioxetane bearing a benzylic anion, which decomposes rapidly with accompanying emission of crimson light. When an anion of chloromalonate (3c) was used as a base, intramolecular cyclopropanation of 3c occurred concurrently with the Michael-addition-induced chemiluminescent decomposition. 相似文献
13.
14.
Jean-François Morizur 《Tetrahedron letters》2007,48(31):5555-5559
The synthesis of new polyfunctional 2-pyrrolidinone derivatives from methyl 2-(carboethoxyhydroxymethyl)acrylate is described. These alkenes present an extremely high reactivity upon Michael addition with primary amines leading to a simple, mild, and efficient route to the preparation of new polyfunctional pyrrolidinones. 相似文献
15.
JiChengCHU HongShengGUO JunBiaoCHANG KangZHAO 《中国化学快报》2004,15(7):785-786
The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N-methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final product was obtained in 20.8% yield. 相似文献
16.
CrystalStructureoftrans-2-(1-Naphthyl)-1-(p-(4',4',5',5'-tetramethyl-4',5'-dihydro-1'H-imidazolyl-1'-oxy-3'-oxide)-phenyl)-im... 相似文献
17.
Yu Dong SHEN Hai Qiang WU Lin Kun AN Zhi Shu HUANG Xian Zhang BU Lian Quan GUb School of Chemistry Chemical Engineering Sun Yat-sen University Guangzhou School of Pharmaceutical Sciences Sun Yat-sen University Guangzhou 《中国化学快报》2005,16(12)
Most of natural and synthetic compounds1-3 with benzofuran moieties exhibit broad spectrum bioactivities, such as antitumor, antifungal, antivirus activities; 5-lipoxygensase inhibitory activity and 5α-reductase inhibitory activity4-7. Moreover, they are also key intermediates for constructing some natural bioactive quinones8.As part of our research program focused on novel ortho-naphthofuranoquinone derivatives, various 3-substituted benzofurans were required as synthetic intermediates. Synt… 相似文献
18.
从三七水溶性成分中首次分离得到一个多羟基吡嗪衍生物 .该化合物经 MS,NMR,1 H-1 H COSY,1 3 C-1 H COSY和 HMBC等鉴定其结构为 2 -( 1 ,2 ,3 ,4 -四羟基丁基 ) -6 -( 2 ",3",4 "-三羟基丁基 ) -吡嗪 .对该分离样品进行了合成对照和药理活性研究 相似文献
19.
A diastereoselective synthesis of functionalized dihydroindolizidine derivatives bearing sulfur moiety was reported with high stereoselectivity via a catalytic sulfur-Michael addition triggered intramolecular aldol-type tandem sequence. This protocol allowed to readily access trans- and cis-dihydroindolizidine products in high yields with moderate to excellent diastereoselectivities under the optimized mild reaction conditions, which also can be easily transformed into various substituted functionalized pyridines incorporating β-quaternary carbon centers. 相似文献
20.
An efficient synthesis of optically active (2R,3R)-2-methyl-3-[(1R)-1-methylprop-2-enyl]cyclopentanone, a useful chiral building block for synthesis of vitamin D and steroids, has been developed starting from readily accessible optically active secondary propargyl phosphate (R)-2, where the asymmetric Michael addition of a chiral allenyltitanium to alkylidenemalonate 3 is a key reaction. 相似文献