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1.
以取代苯乙酮和5-醛基-8-甲氧甲氧基-2-甲基-2-(4'-甲基-3'-戊烯基)-二氢-1-苯并吡喃为原料,经羟醛缩合反应制得两个中间体——7,2',4'-三甲氧甲氧基-6'-羟基-2-甲基-2-(4'-甲基-3'-戊烯基)-二氢-1-苯并吡喃查尔酮(3a)和7,2',4'-三甲氧甲氧基-5'-异戊烯基-6'-羟基-2-甲基-2-(4'-甲基-3'-戊烯基)-二氢-1-苯并吡喃查尔酮(3b);3a经环合和脱保护基反应合成了(±)-Malaysianone A(4a),产率12.9%;3b经脱保护基和环合反应合成了(±)-Tanariflavanones B(4b),产率5.2%。4a和4b的结构经1H NMR,13C NMR和HR-ESI-MS确证。  相似文献   

2.
2,6-二甲基-3,5-二氯-4-吡啶酚糖苷的合成   总被引:4,自引:0,他引:4  
在相转移催化条件下, 使 a-D-乙酰基化溴代的葡萄糖、半乳糖、葡萄糖醛酸甲酯1a, 1b, 1c分别与2,6-二甲基-3,5-二氯-4-吡啶酚(俗称氯吡醇, 氯羟吡啶)作用, 合成了氯吡醇的糖苷: 1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4,6-四-O-乙酰基-β-D-葡萄吡喃糖苷(2a), 1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4,6-四-O-乙酰基β-D-半乳吡喃糖苷(2b), 1-O-(2'6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4-三-O-乙酰基-β-D-葡萄吡喃糖醛酸甲酯(2c)。2a, 2b, 2c分别在甲醇中氨解, 相应得到: 1-O-(2', 6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-葡萄吡喃糖苷(3a), 1-O(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-半乳吡喃糖苷(3b),1-O-(2', 6'-二甲基-3',5'-二氯-(4'-吡啶基)-β-D-葡萄吡喃糖醛酸酰胺(3c)。2c用CH~3ONa/CH~3OH处理, 得到1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-葡萄吡喃糖醛酸甲酯(3d)。  相似文献   

3.
以己二酸为原料,经酯化、肼解后与异硫氰酸苯酯(或对氯异硫氰酸苯酯)反应合成了两个新化合物——对称-N1,N1'-(1,4-丁二基)二(甲酰胺基)-N4,N4'-二(取代苯基)硫脲(3a和3b);3a和3b分别经肼解合环合成了两个新化合物——对称-3,3'-二(取代苯基氨基)-4,4'-二(氨基)-5,5'-(1,4-丁二基)-1,2,4-三唑,其结构经1H NMR,IR和元素分析表征。  相似文献   

4.
以三乙胺为缚酸剂,二苯胺和4,4'-二溴二苯胺分别与三光气反应制得N,N-二苯基氨基甲酰氯(2a)和N,N-(4,4'-二溴二苯基)氨基甲酰氯(2b);2a和2b分别与3-氨丙基三乙氧基硅烷反应合成了两个新型的含非对称取代脲的功能性有机硅氧烷——1,1-二苯基-3-(3-三乙氧基硅基)丙基脲和1,1-(4,4'-二溴二苯基)-3-(3-三乙氧基硅基)丙基脲,其结构经1H NMR,13C NMR和IR表征。  相似文献   

5.
1,1'-联二萘酚(1)经溴代反应制得6,6'-二溴-1,1'-联二萘酚(2);2经苄基保护羟基制得2,2'-二苄氧基-6,6'-二溴-1,1'-联二萘(3);3经Ullmann缩合在6,6'-位引入甲氧基制得2,2'-二苄氧基-6,6'-二甲氧基-1,1'-联二萘(4b);3经Kumada偶联反应在6,6'-位引入正己基制得2,2'-二苄氧基-6,6'-二正己基-1,1'-联二萘(4c);4b和4c经还原脱去苄基制得6,6'-位取代1,1'-联二萘酚(5b和5c);2,5b和5c分别与三氯氧磷反应合成了3种1的6,6'-位取代手性磷酸(6a~6c),其结构经1H NMR和31P NMR表征。其中6c为新化合物。  相似文献   

6.
利用1-[5'-氨基-1'-(4'-氯苯基)-1', 2', 3'-三唑-4'-甲酰基]-4-芳基氨基硫脲在汞盐Hg(OAc)2-HOAc中加热缩合, 制得11种新的2-芳胺基-5-[5'-氨基-1'-(4'-氯苯基)-1', 2', 3'-三唑-4'-基]---1, 3, 4-恶二唑。所有化合物的结构经元素分析, IR、MS以及1H NMR确认。选择代表物作生测试验, 结果表明, 2b, 2k中MIC3.1mg/L时, 对大肠杆菌及金黄色葡萄球菌繁殖有明显抑制。  相似文献   

7.
在Cs OH的CH3OH/DMF溶液中,4,5-二(氰乙硫基)乙二硫撑四硫富瓦烯(1a),4,5-二(氰乙硫基)甲基乙二硫撑四硫富瓦烯(1b),4,5-二(氰乙硫基)丙二硫撑四硫富瓦烯(1c)和4,5-二(氰乙硫基)苯基四硫富瓦烯(2)分别与五(乙二醇醚)二-对甲苯磺酸盐经偶联反应合成了4个新型的非对称四硫富瓦烯环状冠醚衍生物(3a~3c和4),其结构经1H NMR,~(13)C NMR,ESI-MS和元素分析表征。用循环伏安法研究了3a~3c和4对碱金属离子(Na+,Li+,K+和Rb+)的响应性能。结果表明:2,3-二硫-(3',6',9',12'-四氧冠醚)-6,7-丙二硫代四硫富瓦烯(3c)和2,3-二硫-(3',6',9',12'-四氧冠醚)-6,7-苯基四硫富瓦烯(4)对Na+响应较明显,其△E1/21分别为30 m V和45 m V。  相似文献   

8.
合成卡培他滨的新方法   总被引:2,自引:0,他引:2  
朱仁发  陈仕云  何勇 《合成化学》2008,16(1):120-122
1',2',3'-0-三乙酰基核糖与硅醚化的5-氟胞嘧啶缩合制备了2',3'-0-二乙酰基-5'-脱氧-5-氟胞苷(2);2再与氯甲酸正戊酯反应得到2',3'-0-二乙酰基-5'-脱氧-5-氟-N4-[(戊氧基)羰基]胞苷(3);3经皂化合成了卡培他滨(总产率53%),其结构经1H NMR和元素分析表征.  相似文献   

9.
以诺蒎酮为原料,合成了新型蒎烷基吡唑酰胺类衍生物,并对其生物活性进行了研究.诺蒎酮与芳香醛进行缩合反应,得到中间体3-芳亚甲基诺蒎酮2a~2g,2a~2g与水合肼经环化、脱氢芳构化反应,得到新型蒎烷基吡唑类化合物3a~3g;以N,N-二甲基甲酰胺为溶剂,3a~3g与2-氯乙酰胺在碱催化作用下,合成了7种吡唑酰胺类化合物4a~4g.其结构经~1H NMR,~(13)C NMR,IR,和HRMS表征.通过X射线衍射分析测定了化合物2-(6',6'-二甲基-3'-(4'-甲氧基苯基)-4',5',6',7'-四氢-5',7'-桥亚甲基-吲唑-1'-基)乙酰胺(4d)的晶体结构.探讨了化合物3a~3g和4a~4g的抑菌活性和对蚜虫的杀虫活性.实验结果表明,2-(6',6'-二甲基-3'-(4'-氟苯基)-4',5',6',7'-四氢-5',7'-桥亚甲基-吲唑-1'-基)乙酰胺(4g)既具有较好的抑菌效果,同时对紫薇蚜虫也表现出较好的杀虫活性.  相似文献   

10.
以腺苷(2)为原料,经丙酮叉保护2',3'-位羟基得2',3'-O-异丙叉腺苷(3);3经叔丁基二甲硅氯保护5'-羟基得5'-O-叔丁二甲基硅基-2',3'-O-异丙叉腺苷(4);4经二碳酸二叔丁酯保护氨基得到N~6,N~6-二(叔丁氧羰基)-2',3'-O-异丙叉基-5'-O-叔丁二甲基硅基腺苷(5);5用四丁基氟化铵脱去叔丁二甲基硅基合成了新化合物N`6,N~6-二(叔丁氧羰基)-2',3'-O-异丙叉腺苷,总收率54.3%,其结构经~1H NMR,~(13)C NMR,IR和HR-MS表征.  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.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

13.
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   

14.
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   

15.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

16.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

17.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

18.
19.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

20.
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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