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In the search for fulgides with potential semiconductor laser compatibility, 4-adamantylidene-5-dicyanomemylene-3-[1-(2,5-dimethyl-3-furyl)ethylidene]tetrahydrofuran-2-one ( 4 ), along with its regioisomer 4a , have been synthesized from the corresponding fulgide 6 containing a succinic anhydride ring by reaction with malononitrile in the presence of diethylamine. Upon irradiation with a uv light at λmax 350 run, a mixture of 4 and 4a revealed a considerably enhanced bathochromic shift to the visible region, λmax 605 nm as compared with the starting fulgide 6 which, upon analogous uv irradiation, absorbed at λmax 515 nm. In the search for semiconductor-laser-compatible fulgides with increased efficiency for the reverse bleaching reaction, another fulgide (E)–adamantylidene-3-[2,6-dimethyl-3,5-bis(p-diethylaminostyryl)-benzylidene]tetrahydrofuran-2,5-dione ( 10 ) was synthesized in seven steps starting from 2-bromo-m-xylene. However, 10 failed to undergo electrocyclic ring-closure upon irradiation with a uv light at λmax 350 nm. The analogous fulgide 8 , which contains an isopropylidene functionality in place of the adamantyl group of 10 , was resynthesized for comparison, and showed two absorption maxima, one at 545 nm and the other at 620 nm. The missing physico-chemical data for 8 have also been provided.  相似文献   

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(2S,3S)-[3-(2)H1]-4-Methyleneglutamic acid 1a and (2S,3R)-[2,3-(2)H2]-4-methyleneglutamic acid 1b have been synthesised for use in biosynthetic and metabolic studies.  相似文献   

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孙素素  李晴  高卫  李晓天  陈来  张金林 《结构化学》2021,40(1):109-113,4
The target compound(Z)-4-[3-(4-methyl-1,2,3-thiadiazol-5-yl)-3-(4-trifluoromethylphenyl)acryloyl]morpholine was synthesized by the nucleophilic substitution,Horner-Emmons reaction,ester hydrolysis,and condensation.Its structure was characterized by NMR,H RMS and single-crystal X-ray diffraction.The crystal of the target compound belongs to monoclinic system,space group P21 with a=11.5058(15),b=6.6626(10),c=23.184(3)?,V=1777.3(4)?3,Z=8,Dc=1.496 Mg/m3,F(000)=792 andμ=0.229 mm–1.X-ray analysis indicated C–H....O intermolecular H-bonds in this crystal structure.The target compound exhibited 53%curative activity against TMV.  相似文献   

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《Tetrahedron: Asymmetry》2005,16(17):2927-2945
4-[(Heteroaryldiazenyl)methylidene] and 4-([1,2,4]triazolo[4,3-x]azin-3-yl) substituted (1R,5R)-4-1,8,8-trimethyl-2-oxabicyclo[3.2.1]octan-3-ones 6/6′ and 7/7′ were obtained in a one-pot transformation of the enamino lactone 2 with hydrazinoazines 3ag followed by oxidation of the intermediate mixture of isomeric enehydrazines 4/4′ and hydrazones 5/5′ with lead tetraacetate. The oxidation selectivity was dependent on the ratio of isomeric intermediates 4/4′ and 5/5′. Treatment of 7b with lead tetraacetate led to α-acetoxylated compound 11, while bromination of 9b afforded a 1:1 mixture of α-bromination products 12 and 12′, which were separated by medium pressure liquid chromatography (MPLC). The structures of intermediates and products were confirmed by NMR and X-ray diffraction.  相似文献   

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Structural alteration of the Nb-substituents of psilocin (3-[2-dimethylamino)ethyl]indol-4-ol) ( 12a ) has led to a number of compounds containing known pharmacophoric groups. Further, it is hoped that the subtle changes in the nature of these substituents may lead to a clearer understanding of the structure-activity relationships of the 4-hydroxytryptamine hallucinogens.  相似文献   

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Electronic spectra of thirteen title compounds were measured and the substituent effect on max and max were discussed. It was found that there is a disturbance of mutual electronic interaction of substituent by a steric ortho-effect. The obtained results provide evidence that the investigated 2-akylamino compounds exist in amino form.Department of Organic Chemistry, Academy of Economics, Wroclaw PL-53-432. Published in Khimiya Geterot siklicheskikh Soedinenii, No. 9, pp. l228–l231, September, 1996. Original article submitted August 20, 1995.  相似文献   

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New 2-[2-(3,5-dimethylphenoxy)ethyl]thio derivatives of pyrimidin-4(3H)-one containing various substituents at positions 5 and 6 of the pyrimidine ring were synthesized. It was shown that alkylation of 2-thiouracils with 1-bromo-2-(3,5-dimethylphenoxy)ethane in DMF takes place exclusively at the sulfur atom. The obtained 6-benzyl and 6-(2,6-difluorobenzyl) derivatives have clearly defined virus-inhibiting properties with respect to type 1 human immunodeficiency virus in vitro and suppress its reproduction by 50% at concentrations of 1.3 and 11.2 mM respectively.  相似文献   

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通过E-[4-[2-(4-羟基苯基)乙烯基]吡啶与1,n-二溴烷烃亲核取代反应合成了4,4’-[1,n-亚烷基双[(E)-2-(4-氧苯基)乙烯基]]双吡啶[n=2(Ia),3(Ib),4(Ic),6(Id)].用元素分析、红外、紫外和质子核磁共振谱鉴定了Ia-Id的结构.将Ia-Id的稀溶液用中压汞灯和低压汞灯交替照射,发现其分子内光环加成反应的存在,并且随着亚烷基碳链的延长,反应速度加快.研究还发现锌离子可以与毗陡环上氮原子发生螯合作用使分子内光环加成反应加快.本文化合物荧光很弱,在较高浓度下有较强分子间激基缔合物荧光.  相似文献   

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