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1.
通过2-取代1,3,4-恶二唑-5-硫醇1a-1f和头孢菌素母体7-ACA反应,制得头孢菌素中间体2a-2f,用氨噻唑肟活性酯3和1-芳基-1H-1,2,3-三唑-4-甲酰氯4a-4e分别和头孢菌素中间体缩合制得头孢菌素新衍生物5a-5b和6a-6h,新化合物的结构经^1H NMR,IR及MS确认,初步体外抗菌结果表明,头孢菌素5a-5b对革兰氏阳性和阴性菌有显著抑制活性,而6a-6h对其则显示出中等程度的抑制活性。  相似文献   

2.
5-芳基-2-呋喃甲酸及其衍生物具有调节植物生长等作用[4].我们通过大量的实验,选用PTC法,利用5-芳基-2-呋喃甲酰氯与芳胺和芳氧基乙酰肼反应,合成了新化合物Ⅱ和Ⅳ:RCOClO(Ⅰ)ArNH2/PEG-400→RCONHAr(Ⅱ)ONaOH/...  相似文献   

3.
借处理2-羟基-5-(2-苯基-4-喹啉基)-1,3,4-恶二唑同PCl5/POCl3之间的反应合成了2-氯-5-(2-苯基-4-喹啉基)-1,3,4-恶二唑(3)和通过2-Yu基-5-(2-苯基-4-喹啉基)-1,3,4-恶二唑的甲基化,然后氧化制得2-甲磺酰基-5-(2-苯基-4-喹啉基)-1,3,4-恶二唑(6)。并分别研究了3和6同胺、叠氮及肼的反应,得到2,5-二取代的恶二唑新衍生物。初  相似文献   

4.
借处理2-羟基-5-(2-苯基-4-喹啉基)-1,3,二唑同PCl_5/POCl_3之间的反应合成了2-氯-5-(2-苯基-4-喹啉基)-1,3,4-二唑(3)和通过2-基-5-(2-苯基-4-喹啉基)-1,3,4-二唑的甲基化,然后氧化制得2-甲磺酰基-5-(2-苯基-4-喹啉基)-1,3,4-二唑(6).并分别研究了3和6同胺、叠氮及肼的反应,得到2,5-二取代的二唑新衍生物.初步观察了部分化合物的抗菌活性.  相似文献   

5.
利用1-芳基-5-甲基-1H-1,2,3-连三唑-4-甲酰氯-,苯并三唑-1-乙酰氯以及5-甲基异恶唑-3-甲酰氯在低温,丙酮-水条件下,分别用7-ACA,7-DCA和7-ADCT反应,制得13种头孢菌素衍生物3a-3i,6a-6b和9a-9b,所有化合物经葡萄糖聚糖凝胶柱层析和离心薄层层析反复精制得纯品,新化合物结构经元素分析,IR,^1HNMR和FAB-MS确认,其中代表物显示出强的抗菌活性。  相似文献   

6.
合成了两个异亚硝基乙酰丙酮-N-芳基亚胺的Pd(Ⅱ)配合物,PdCl(C6H5-IAI)(C6H5NH2)(1)和PdCl(p-CH3C6H4-IAI)(p-CH3C6H4NH2)(2),并测定了配合物1的晶体结构。配合物1晶体属正交晶系,空间群为Pca21,晶胞参数a=1.8587(4)nm,b=0.9380(2)nm,c=2.1237(4)nm,Z=8,F(000)=1760,μ=1.160m  相似文献   

7.
利用1-苯基-3-甲基-5-氯-4-吡唑甲酰基异硫氰酸酯(1)与芳酰肼(Ⅱ)的加成反应合成了系列新的酰胺基硫脲衍生物(Ⅱ)并将Ⅲ在酸性条件下进行环化反应得到2-取代吡唑甲酰基氨基5-芳基-1,3,4-噻二唑(Ⅳ)生物活性测定结果表明部分化合物Ⅲ和Ⅳ具有较好的除草活性。  相似文献   

8.
6,7—取代—1H—苯并(de)异喹啉—1,3(2H)二酮的合成   总被引:1,自引:0,他引:1  
严宏宾  蔡良珍 《合成化学》1998,6(2):196-199
从二氢苊出发合成了6-溴-7-氨基2-(2′,4′-二甲基)苯基-1H-苯并(de)异喹啉-1,3(2H)-二酮,6-甲氧基-7-氨基-2-(2′,4′-二甲基)苯基-1H-苯并(de)异喹啉-1,3(2H)-二酮和6,7-二氨基-2-(2′,4′-二甲基)苯基-1H-苯并(de)异喹啉-1,3(2H)-二酮,测定了它们的荧光量子产率,讨论了分子内重原子溴和给电子基对化合物荧光性质的影响。  相似文献   

9.
王长凤  刘秋田 《结构化学》1996,15(6):495-498
4-氨基-3,5-二甲基-1,2,4-三唑与水杨醛缩合形成4-(邻羟苯基亚甲基)-亚胺-03,5-二甲基-1,2,4-三唑Schiff碱(SATZ),该Schiff碱与Cu(ClO4)2.6H2O形成配合物Cu(satz)2.6H2O,分子式为C22H22CuN8O2.6H2O。  相似文献   

10.
黄小荣  周锡庚 《结构化学》1998,17(6):449-453
(C5H4CH3)3Ho和(C5H4CH3)2Ho(C5H5)与5-本基四唑在THF中反应,得到了复合产物「(C5H4CH3)2HoN4CPh」2.「(C5H4CH3)(C5H5)HoN4CPh」2,该晶体属三斜晶系,P1空间群,晶胞参数为a=9.386(3),b=13.071(3),c=16.571(2)A,α=86.90(1),β=74.61(2),γ=77.30(2)°,V=1912.8(8  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
Siqi Li  Xingpeng Chen  Jiaxi Xu 《Tetrahedron》2018,74(14):1613-1620
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   

19.
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   

20.
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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