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4-羟基香豆素类化合物与4-羟基喹啉酮类化合物是一类重要的有机杂环化合物,因为其良好的生理活性,被广泛应用于抗菌、抗炎、抗HIV、抗肿瘤等药物结构中。 本文用4-羟基香豆素类化合物或4-羟基喹啉酮类化合物作为底物、以硫磺粉(S)为硫源、以碘苯类衍生物作为芳基源,在氯化铜催化作用下合成了3-芳硫基-4-羟基香豆素类化合物和3-芳硫基-4-羟基喹啉酮类化合物。 该方法使用环境友好的硫磺粉为硫源替代有机硫,操作简单、无污染、成本低廉,为该类化合物的绿色合成提供了新的方案。 相似文献
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异黄酮化合物具有心血管活性[1],雌激素活性[2]及抗骨质疏松[3]活性等。3 苯基 4(1H)喹啉酮衍生物是异黄酮化合物的等电子体,文献报道它具有与异黄酮化合物相似的心血管活性[4]和抗肿瘤[5]活性。结构中具有氟原子的化合物大多能改善脂溶性,增强生理活性,且能选择性作用于脑细胞及脑血管;喹诺酮类抗菌药中具有优良抗菌活性的化合物几乎都含有氟原子。我们对含氟的3 苯基 4(1H)喹啉酮类化合物进行了研究。以氟氯苯胺为原料,合成了其7 氯衍生物(化合物A1~A4),及5 氯衍生物(化合物B1~B4),其中7 氯衍生物为主产物,合成路线如下:化合… 相似文献
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杂环化合物大多具有一定的生物活性,而喹啉类杂环化合物是具有生物活性和药理活性最常见的一类杂环化合物.很多喹啉衍生物具有杀菌、抗菌、抗高血压、抗抑郁、抗过敏、抗疟疾、抗肿瘤和抗癌等生物活性和药理活性[1].大部分喹啉衍生物是通过化学方法合成出来的,如磷酸氯喹(Chloroquine phosphate)、扑疟喹(Plasmoquine)、磷酸伯喹(Primaquine phosphate)等抗疟疾药物[2]. 相似文献
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《化学研究与应用》2020,(7)
结核病一直困扰着人类的健康。谷氨酸5-激酶(G5K,Glutamate 5-Kinase)作为新型抗结核药物靶标,小分子活化剂与其结合后,激活生物合成途径,会产生过量的脯氨酸和活性氧,从而杀死结核分枝杆菌(Mtb)。本文基于结核分枝杆菌谷氨酸5-激酶(Mtb_G5K)的一级序列,采用同源模建的方法构建Mtb_G5K蛋白三维结构并对其优化,运用三种方法分别对模型的各个方面进行评估,从而得到合理的蛋白质三维模型;构建小分子并将其能量最小化获得药物分子的最低能量构象,用Autodock将小分子对接到Mtb_G5K的活性位点;分析探讨[3,2-c]喹啉类小分子结合模式,观察蛋白与小分子之间的相互作用并预测具有稳定结合的高活性药物,从而推断出喹啉环的取代基采用相对分子质量较大的官能团能够增强药物小分子的酶催化活性。本研究结果对将来抗结核小分子的研发设计提供了新的思路。 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献
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A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL. 相似文献
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A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions. 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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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular SN2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 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