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以2-溴-3,3,3-三氟丙烯(1)为原料,经卤素-镁交换反应制得中间体三氟异丙烯基格氏试剂(2);2分别与CO2,正丁醛,苯甲醛和苯甲酰氯反应合成了2-三氟甲基丙烯酸(3a),2-三氟甲基-1-己烯-3-醇(3b),1-苯基-2-三氟甲基-2-丙烯-1-醇(3c)和1-苯基-4-三氟甲基-4-丁烯-1-酮(3d),其中3d为新化合物,其结构经1H NMR,13C NMR,IR,MS和元素分析表征。考察了交换试剂、物料比、温度和反应时间对3a产率的影响。在最优反应条件[以i-Pr Mg Br/Li Cl为交换试剂,1 50 mmol,n(2-溴丙烷)∶n(1)=1.25∶1.00,于-60℃反应2 h]下,3a收率64.3%。 相似文献
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以2-氨基-5-氟苯甲酸为起始原料,与醋酐酰化关环制得6-氟-2-甲基噁嗪-4-酮(1); 1在80%水合肼中回流反应制得6-氟-2-甲基-3-氨基-4(3H)-喹唑啉酮(2); 2分别与羟基芳醛和杂环芳醛反应合成了6个6-氟-4(3H)-喹唑啉酮类Schiff碱(3a~3f),其中3b~3f为新化合物,其结构经1H NMR, 13C NMR, IR和元素分析表征。采用琼脂扩散法研究了3a~3f对大肠杆菌、金黄色葡萄球菌和枯草杆菌的抑制活性。结果表明:用药浓度为400 μg·mL-1时,3a~3f对受试菌种均有一定的抑制活性,其中6-氟-2-甲基-3-(4-吡咯苯亚甲氨基)-4(3H)-喹唑啉酮(3c)抑菌活性最强,对大肠杆菌和枯草杆菌的抑菌圈直径分别为9.38 mm和9.00 mm。 相似文献
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以3-[(3-氨基-4-甲基氨基苯甲酰)吡啶-2-基氨基]丙酸乙酯为原料,与4-氰基-3-氟苯取代基乙酸经环化反应制得3-【【2-{[(4-氰基-3-氟苯取代基)甲基]-1-甲基-1-H-苯并咪唑-5-基}羰基】吡啶-2-基】氨基丙酸乙酯(3a, 3e); 3经水解和酰胺化反应制得3-【【【2-{[(4-氰基-3-氟苯基)取代基]甲基}-1-甲基-1H-苯并咪唑-5-基】羰基】吡啶-2-基氨基】丙酰取代胺基(6a~6h);6与乙酰氧肟酸经环合反应合成了8个新型的苯并咪唑衍生物(7a~7h),其结构经1H NMR和HR-ESI-MS表征。抗凝血活性结果表明: 7a和7c的抗凝血活性最好,其aPTT值分别为(83.1±4.2) s和(80.7±2.9) s,优于阳性对照药达比加群酯(75.3±2.1)s。 相似文献
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以1-氟-2-硝基芳烃和反式-4-氨基环己醇盐酸盐为原料,经亲核取代、还原、环化及缩合等反应合成了15个新型的2-氨基苯并咪唑类EGFRT790M抑制剂(6a~6o),其结构经1H NMR, 13C NMR和HR-MS(ESI)表征。分别采用ELISA法和SRB法测定了6a~6o的体外酪氨酸激酶抑制活性和体外抗肿瘤活性。结果表明:6l对EGFRT790M/L858R的抑制活性最好,其IC50为45.6±18.8 nmol·L-1,优于先导化合物N-{1-[(1R,4R)-4-羟基环己基]-7-甲基-1H-苯并[d]咪唑-2-基}-3-(三氟甲基)苯甲酰胺(6,IC50为136.7±9.1 nmol·L-1),且对EGFRT790M的选择性高达219倍;6a, 6e, 6h和6i对人肺腺癌细胞(NCI 1975)的抑制活性较好,其IC50值分别为1.929±0.347, 2.168±0.819, 2.335±0.787和1.930±0.529 μmol·L-1,优于先导化合物6(2.653±1.395 μmol·L-1)。 相似文献
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以6-氯邻氨基苯甲酸为起始原料,与醋酐酰化关环制得6-氯-2-甲基噁嗪-4-酮(1);1在80%水合肼中回流反应制得6-氯-2-甲基-3-氨基-4(3H)-喹唑啉酮(2);2与羟基芳醛反应合成了4种新型的6-氯-4(3H)-喹唑啉酮类Schiff碱(4a~4d),其结构经1H NMR,13C NMR,IR和元素分析表征。采用琼脂扩散法研究了4a~4d对金黄色葡萄球菌(A)、大肠杆菌(B)和枯草杆菌(C)的抑制活性。结果表明:用药浓度为300 mg·m L~(-1)时,4a~4d对A~C均有一定的抑制活性,其中6-氯-2-甲基-3-(5-甲基-2-羟基苯亚甲氨基)-4(3H)-喹唑啉酮(4c)抑菌活性最强,对A~C的抑菌圈直径分别为8.8 mm,11.9 mm和9.6 mm。 相似文献
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An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
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
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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
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An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction. 相似文献
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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
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The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed. 相似文献
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Xi-Liu YunWen-Ying Bi Jian-Hui HuangYu Liu Daisy Zhang-NegrerieYun-Fei Du Kang Zhao 《Tetrahedron letters》2012,53(38):5076-5080
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring. 相似文献
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Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles. 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
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
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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