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1.
以相转移催化法和Koenigs-Knorrs反应,使α-溴代乙酰基木糖与2-取代-5-氟脲嘧啶或其银盐作用,合成了11个未见文献报道的糖苷类化合物。其结构经IR、1HNMR、MS等证实。其中有些化合物有一定的抗肿瘤活性。  相似文献   

2.
1-芳酰基-4-芳基氨基脲类化合物的合成及表征   总被引:8,自引:0,他引:8  
利用N-取代三氯乙酰胺与芳基酰肼反应,合成了6个新的1-芳酰基-4-芳基 氨基脲类化合物,其结构经IR,^1H NMR和元素分析证实。初步生物活性测试表明 ,具有一定的除草活性。  相似文献   

3.
分别研究了N,N-二取代-α-氯代乙酰胺类化合物及N,N-二取代-α-二硫代磷酰基乙酰胺类化合物结构与除草活性的定量关系。结果表明:氮原子上取代基的大小对两类化合物的除草活性具有相同的影响,只是最适宜的疏水性不同,两类化合物可能具有相同的作用机制。  相似文献   

4.
γ-[N_1-取代-1,4,5,6-四氢(及1,6-二氢)-6-氧-3-哒嗪酰胺基]丁酸乙酯类化合物的合成许凤荣,王书玉,徐萍,黎辉,胡长风,欧阳荔(北京医科大学药学院、分析计算中心波谱室,北京,100083)关键词6-氧-3-哒嗪酸,哒嗪类衍生物,...  相似文献   

5.
6-取代基-2-氧-3,4-二氢呋喃并喹啉类化合物用氢化钠还原所生成的醇钠与硫代磷酰氯缩合制备3,4-二氢呋喃并喹啉化合物,通过 ̄1HNMR,MS和元素分析鉴定了它们的结构,并初步测试了它们的抑菌活性.  相似文献   

6.
3,7,10-三甲基杂氮硅三环类化合物的合成及结构分析鲁开娟,王天用(中国科学院化学研究所北京100080)带有N-Si配位键的杂氮硅三环类化合物,其性质主要取决于环骨架结构和硅原子上所连接的R取代基。作者曾将杂氮硅三环化合.物的一个五之环结构扩大成...  相似文献   

7.
邻位取代1,2-二苯乙烯催化不对称二羟基化反应张生勇,孙晓莉(第四军医大学化学教研室西安710032)关键词 不对称二羟基化,手性二醇近年催化的反式稀烃的不对称二羟基化反应取得明显进展[1],但催化的邻位取代的1,2-二苯乙烯类化合物的不对称二羟基化...  相似文献   

8.
由烃基异硫氰酸酯与取代邻肼基苯甲醚类化合物的加成反应,合成了10种新的取代氨基硫脲类化合物,其结构经元素分析、IR、^1HNMR等确证。初步生理活性实验表明,对金黄色葡萄球菌和大肠杆菌都有不同程度的杀菌和抑菌作用。  相似文献   

9.
在乙醇为溶剂,乙醇钠为碱的条件下,标题类化合物归1a~c,3a,4a与胍缩合反应生成相应的嘧啶类化合物2a~c,3b,3c,4b。在以DMF为溶剂,乙醇钠为碱的条件下,化合物与胍反应可生成2-氨基-4-二甲氨基-6-苯基嘧啶2a’。该缩合反应的特点为标题类化合物与肌缩合生成嘧啶类化合物的同时,将乙氧基或二甲氨基引入嘧啶环的确定位置。为新的嘧啶类化合物。  相似文献   

10.
合成了一系列取代甲基硫代苯并咪唑类化合物,并在过氧乙酸的氧化下得到了 取代甲基亚磺酰基苯并咪唑类化合物,收率较好(79%~97%),代替了用间氯过氧苯 甲酸进行氧化,反应过程稳定,降低了成本。  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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