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1.
5-甲基-2-巯基-1,3,4-噻二唑的合成李占才李淑勉方少明侯守君聂晓兵林烨(郑州轻工业学院化工系郑州450002)关键词5-甲基-2-巯基-1,3,4-噻二唑乙酰肼N-乙酰肼基二硫代甲酸钾中图分类号O626.275-甲基-2-巯基-1,3,4-噻...  相似文献   

2.
报道了1,9-乙撑基蒽和1,9-乙撑基-10-甲基蒽在CHCl3/定点 与碘反应的机理,它们的单电子氧化生成游离基正离子,该过程存在侧链去质子和吡啶进攻蒽环两种竞争反应,蒽环上引入乙撑基使侧链氧化远比环氧化占优势,乙撑基比甲基容易去质子。  相似文献   

3.
聚磷酸酯—聚氨酯药物释放材料的合成   总被引:4,自引:0,他引:4  
报道了一类新型生物可降解和生物相容性药物释放材料聚磷酸酯-聚氨酯的合成和表征,研究了这类聚合物的体外降解及其对牛血清白蛋白的释放性能。  相似文献   

4.
4-溴-5-甲基靛红分别与单过邻苯二甲酸,过硫酸钾-硫酸两种氧化剂发生Baeyer-Villiger反应,生成两种同分异构体:5-溴-6-甲基-1H-苯并[1,3]恶嗪-2,4-二酮和新化合物5-溴-6-甲基-1H-苯并[1,4]恶嗪-2,3-二酮。利用MS、^13CNMR、^1HNMR、IR反应,单过邻苯二甲醇,IR对产品结构进行了分析鉴定。  相似文献   

5.
以1-甲基-3-乙基(4-氯)-5-哟唑甲作原料,经两步得到4-氨基-3-(1-甲基-3-乙基(4-氯)-5-吡唑基)-1,2,4-三唑-5-硫酮(3),3再与取代酸反应,得到一系列3(1-甲基-3-,乙基(-4-氯)-5-吡唑基)-6-取代均三并「3,4-b」-1,3,4-噻二唑(4,5,6),元素分析、HNMR、IR和MS确定了它们的结构,初步生侧结果表明,3具有植物生长调节活性,4b、4d、  相似文献   

6.
利用固-液相转移催化法合成了7种α,ω-双[1-(2-甲基-4-硝基咪唑基)]烷烃和20种1-烷基-2-甲基-4-硝基咪唑类化合物,大多数化合物收率在85%以上。初步生物活性试验结果表明,部分化合物具有一定的抗炎、抗菌、镇痛、镇静或抗脑缺氧活性。  相似文献   

7.
李叶芝  田颜清 《合成化学》1996,4(2):168-170
γ-甲基-δ酮己酸,γ-异丙基-δ-酮己酸在碘化N-甲基-2-氯吡啶盐存在下分别用(R)-四氢噻唑-2-硫酮-4-羧酸乙酯反应,得到光学活性的(R)-N-(γ-甲基-δ-酮己酰基)四氢噻唑-2硫酮-4羧酸乙酯(la)及光学活性的(R)-N-(γ-异丙基-δ-酮己酰基)四氢噻唑-2-硫酮-4-羧酸乙酯(1b),la,lb分别同(R,S)-α-苯乙胺反应得到光学活性的酰胺2a,2b,同时使(R,S)=  相似文献   

8.
研究了在氯化氢-乙醇溶液或乙醇溶液中,2,4-二羟基苯乙酮与甲醛和芳胺的Mannich反应,分别得到了5个2,4-二羟基-3-芳氨基甲基苯乙酮和5个8-乙酰基-3-芳基-3,4-二氧-5-羟基-2H-1,3-苯并恶嗪新化合物,用元素分析,IR,HNMR,MS,UV确定了它们的结构,并成功地实现了2,4-二羟基-3-芳氨基甲基苯乙酮和8-乙酰基-3-芳基-3,4-二氢-5羟基-2H,1,3-苯并恶嗪  相似文献   

9.
研究了3-(1H-苯并三唑-1-亚甲基)-4-氨基-5-巯基-1,2,4-三唑与取代苯甲酸在三氯氧磷催化下的反应,制得10种新的3-(1H-苯并三唑-1-亚甲基)-1,2,4-三唑并[3,4-b]-1,3,4噻二唑,通过元素分析,IR、^1HNMR和MS确证了它们的结构并讨论了其波谱性质。  相似文献   

10.
研究了芳香醛与3-甲基-1-苯基-5-吡唑啉酮在室温固相、熔融状态及Lewis酸催化下的缩合反应,分别得到4,4'-甲太-双(3-甲基-1-苯基-5-吡唑啉酮)2-4-芳甲太-3-甲基-1-苯基-5-吡唑啉1.实验表明,在固体状态下,2主要以烯醇式存在,受势时或在溶液中两者可相互转化。  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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