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合成5—氟尿嘧啶—N^1—甲酰基异亮氨酸的新方法 总被引:4,自引:2,他引:2
合成5-氟尿嘧啶-N~1-甲酰基异亮氨酸的新方法叶发青(咸宁医学院化教研室,咸宁437100)5-氟尿嘧啶-N1-甲酰基异亮氨酸具有较高的抗肿瘤活性,并且毒副作用较低[1]。对此类药物的开发具有较广泛的应用前景。它也是合成含5-氟尿嘧啶的高分子抗癌药?.. 相似文献
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以氯丙酮和硫脲为起始原料,经环合、Vilsmeier甲酰化、重氮化还原得到头孢托仑匹酯关键中间体4-甲基-5-甲酰基噻唑,反应总收率为42.8%。重点考察了Vilsmeier甲酰化反应中双(三氯甲基)碳酸酯(BTc)/DMF用量、反应温度和反应时间对中间体4收率的影响,得出了较佳的工艺条件,并对其反应机理进行了探讨。 相似文献
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用Curtius重排反应合成4-氯苯基异氰酸酯 总被引:4,自引:2,他引:2
按Curtius重排反应原理 ,采用叠氮化钠与4-氯苯甲酰氯反应合成4-氯苯基异氰酸酯。该法反应条件温和 ,操作简便 ,产率高 相似文献
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The formation of oxazolidone from 9,10-epoxyoctadecane and phenylisocyanate was studied. One branch of epoxidized vegetable
oil with one epoxy group per chain corresponds to 9,10-epoxyoctadecane. This model could explain the probability of oxazolidone
formation from natural oil-derived epoxides. Epoxidized natural oils are TG consisting of glycerin and three FA with or without
one to three epoxy groups in the middle of the chain. To study oxazolidone formation from an internal epoxy group without
possible interference from the side reactions on the ester group, 9,10-epoxyoctadecane was selected as the most appropriate
model compound. Epoxy groups in the middle of allong aliphatic chain are of low reactivity toward isocyanates, and preparation
of oxazolidones requires fairly harsh conditions such as high temperatures and catalysts, which also promote side reactions.
The dominant side reaction is rearrangement of the epoxy groups. We found that the direction and magnitude of the rearrangement
and the yield of any particular product depended on the catalyst used. Lithium chloride, aluminum trichloride, and zinc iodide
catalyzed oxazolidone formation, along with the catalysis of side reactions such as ketone and carbonate formation. Aluminum
trichloride showed the highest conversion of 9,10-epoxyoctadecane to oxazolidone. Aluminum triisopropoxide, triphenylantimony
iodide, and imidazole did not catalyze the formation of oxazolidone. They were effective as catalysts of epoxy group rearrangement
and promoted the formation of hydroxyl, ketone, and carbonate compounds. Hydroxyl groups reacted with isocyanate to produce
urethane. 相似文献
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A facile synthesis of two novel diisocyanates containing methylene groups and preformed imide structure is described. Furthermore, six thermally stable and soluble polyimides were synthesized by polycondensation of these two diisocyanates with pyromellitic dianhydride (PMDA), 3, 3 ′,4, 4 ′‐benzophenonetetracarboxylic dianhydride (BTDA) and hexafluoroisopropylidene‐2,2‐bis‐(phthalic anhydride) (6FDA) in N,N ‐dimethyl acetamide. All monomers and polymers were characterized by conventional methods and their physical properties such as solution viscosity, solubility properties, thermal stability and thermal behaviour were studied. © 1999 Society of Chemical Industry 相似文献
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以2-氯腺嘌呤和1,2,3,5-四乙酰基核糖为原料,四氯化锡为催化剂,在130℃下反应15min,得到中间体2-氯腺嘌呤-2’,3’,5’-三乙酰基核苷。室温下用氨的甲醇饱和溶液脱酰基,在乙醇中进行结晶,得到白色2-氯腺苷粉状晶体,收率70.2%,纯度(HPLC)≥99.0?,155℃发生分解。 相似文献
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高效萃取剂LIX841是一种高效的铜萃取剂,结构为2-羟基-5-壬基苯乙酮肟,实验通过壬基酚与乙酸酐,80℃合成中间产物壬基酚乙酸酯,经分离提取,所得中间产物溶于四氯乙烯并在120℃下持续1.5h重排反应得壬基苯乙酮,所得产物在85℃与盐酸羟胺溶液混溶反应2h,得终产物2-羟基-5-壬基苯乙酮。 相似文献
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A new aromatic dicarbonylazide (3) bearing three preformed imide rings was synthesized by treating N-[3,5-bis(trimellitimido)phenyl]phthalimide (1) with thionyl chloride followed by a nucleophilic reaction with sodium azide. A novel family of fully aromatic poly(urethane-imide)s with inherent viscosities of 0.19-0.24 dl g−1 were prepared from triimide-dicarbonylazide 3 and various aromatic diols. The polyaddition reactions readily proceeded in desirable yields as one-pot reactions starting from 3 without separately synthesis of the corresponding diisocyanate. All of the resulted polymers were thoroughly characterized by spectroscopic methods and elemental analyses. The poly(urethane-imide)s exhibited an excellent solubility in a variety of polar solvents. Crystallinity nature of the polymers was estimated by means of WXRD. The glass transition temperatures of the polymers determined by DSC method were in the range of 197-219 °C. The 10% weight loss temperatures of the poly(urethane-imide)s from their TGA/DTG curves were found to be in the range of 391-412 °C in nitrogen. The films of the polymers were also prepared by casting the solution. 相似文献