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1.
樊宏宇 《合成化学》2017,25(10):851-855
以连翘苷为原料,依次经水解反应、氯化铝/吡啶催化的去甲基化反应和差向异构化反应,合成了两个连翘脂素去甲基衍生物(1和2),其结构经1H NMR, 13C NMR, 2D NMR(COSY, NOESY, HSQC, HMBC), IR和MS(ESI)确证。经结构解析对比,1和2与连翘苷的大鼠体内次级代谢产物一致。  相似文献   

2.
以D-葡萄糖为原料,经碳苷化反应,酰化反应和脯氨酸-DIPEA催化的aldol反应制得2个碳苷糖[1-(4'-羟基苯基)-4-C-β-四乙酰基葡萄糖基-3-烯-2-酮(5a)和1-(3-羟基苯基)-4-C-β-四乙酰基葡萄糖基-3-烯-2-酮(5b)];5与琥珀酸维生素D2经Steglich酯化反应合成了2个新型碳苷糖类维生素D2衍生物,其结构经1H NMR,13C NMR和HR-ESI-MS表征。  相似文献   

3.
周俊  郭振楚 《合成化学》2008,16(2):186-188
通过Sehmidt糖苷化反应,合成了2个新化合物2-脱氧-2-氨基基-β-D-吡喃葡萄糖氮苷,其结构经1H NMR,IR和元素分析表征.  相似文献   

4.
周颖钰  杨劲松 《合成化学》2019,27(2):141-144
以N-乙酰氨基葡萄糖为原料,经烯丙基化、苯亚甲基化、苄基化和选择性开环等4步反应,合成了2-乙酰氨基-2-去氧-3,6-二-氧-苄基-α-D-吡喃葡萄糖烯丙基苷,总收率53.4%,其结构经1H NMR, 13C NMR和LC-MS(ESI)确证。  相似文献   

5.
手性氨基醇作为催化剂广泛应用于多种不对称合成反应中。以D-葡糖胺为原料设计合成一系列新型手性β-氨基醇。D-葡糖胺首先与氯甲酸甲酯缩合,再先后经过甲基化、苄叉保护、碱性水解反应,得4,6-O-苄叉基-2-脱氧-2-氨基-α-D-吡喃葡萄糖甲苷,进一步将其通过N-烃化反应或N-磺酰化反应合成得手性β-氨基醇。产物结构经1H NMR,13C NMR和MS表征确证。  相似文献   

6.
合成双醋瑞因的新方法   总被引:1,自引:0,他引:1  
以芦荟素为原料,经脱苷、氧化反应得到大黄酸(4);4经三氟甲磺酸锌催化的乙酰化反应合成了双醋瑞因,总收率86.2%,其结构经1H NMR,IR和MS确证。  相似文献   

7.
孟令国  杨明明 《合成化学》2011,19(6):796-798
以邻羟基苯乙酮衍生物为原料,经溴化反应和叠氮化反应合成了一系列邻羟基α-叠氮苯乙酮衍生物,其结构经1H NMR,13C NMR,IR及HR-MS表征.  相似文献   

8.
以甲基-α-D-吡喃甘露糖苷为原料,经碘代、还原、Wittig缩合、复分解关环、氧化、Michael加成、Mitsunobu反应、氧化及氨解等9步反应合成了一个五碳环腺苷类化合物重要中间体——2',3'-O-异丙叉五碳环腺苷,总产率20%,其结构经1H NMR,13C NMR确证。  相似文献   

9.
以对羟基苯甲醛为原料,经酚羟基保护、醛基还原、氯代、氰化、水解、酯化和还原反应制得关键中间体4-苄氧基苯乙醇(6);6与溴代四乙酰基葡萄糖偶联后脱保护基合成了红景天苷,总收率12.8%,其结构经1H NMR,13C NMR,IR和HR-MS确证。  相似文献   

10.
刘海彬  赵策  潘宁宁  刘晓宇  白林 《合成化学》2018,26(10):749-752
以3,4-二羟基苯甲酸乙酯和2-氯乙基单甲醚为起始原料,经烷氧基化、硝化、还原、环化、氯化、胺化和缩合反应合成了一个含缩氨基硫脲结构的新型喹唑啉化合物,其结构经1H NMR, 13C NMR和MS(ESI)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.
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.
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   

14.
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   

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 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   

17.
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   

18.
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   

19.
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   

20.
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   

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