一种胞苷衍生物的合成

以胞苷为原料,首先通过单乙酰化反应保护-NH2;再分别用二对甲氧基三苯甲基氯和氯甲氧基三异丙基硅烷保护5-′OH和2-′OH;被保护的胞苷经磷酰化反应合成了一种用于制备RNA长链的胞苷衍生物单体——N-乙酰基-5′-O-二对甲氧基三苯甲基-2′-O-三异丙基硅氧甲基-3′-O-双(N,N-二异丙基氨基)(2-氰乙氧基)磷基胞苷(1),总收率29.8%。1及其中间体的结构经1H NMR,MS和元素分析表征。     

伪异胞苷类化合物的合成

利用Wittig反应合成了一系列伪异胞苷类化合物,通过改进实验条件提高了关键中间体的收率,并深入研究了保护的核糖甲氧基丙烯酸乙酯与各种取代的胍和脒的缩合条件.     

异苯并吡喃和异苯并呋喃衍生物合成研究进展

异苯并吡喃和异苯并呋喃是一类重要的杂环化合物, 许多天然产物中含有异苯并吡喃或异苯并呋喃结构单元. 由于其广泛的生物及药物活性, 它们的合成方法受到广泛关注. 综述了异苯并吡喃和异苯并呋喃衍生物的主要合成方法.     

氨基酸甲酯取代的尿苷及其衍生物的合成方法及应用

针对目前临床中所面临的耐药性问题,为开发具有抗肿瘤活性的新型结构化合物,以尿苷为原料,首次合成出具有新型结构的氨基酸甲酯取代的尿苷及其衍生物,反应路径合理,后处理简单;对合成的目标化合物进行了初步的抗肿瘤活性实验,结果显示设计合成的甘氨酸甲酯取代的尿苷对肿瘤有一定的抑制作用,为抗肿瘤药物研究奠定重要的基础。     

尿苷环甘油磷脂缀合物的合成

报道尿苷２－烷基（酰基）－１，３－甘油硫代环磷酸酯的合成，用碘活化的六乙基亚磷酰三胺作为磷酸化试剂，分离得到了硫代环磷酸酯的两个顺反异构体。初步生物活性测试结果表明，该化合物具有一定的细胞毒性。     

1,2,3,4—四氢—2—苄基异喹啉酮—4衍生物的合成

1,2,3,4-四氢-2-取代异喹啉酮-4衍生物中有不少具有重要的药理活性。许多学者进行了这一方面的合成工作。作者根据Hanna等     

新型异噁唑衍生物的合成及其抗菌活性

5-乙酰胺甲基-3-[3-氟-4-(1-哌嗪基苯基)]异噁唑啉与氯乙酰氯反应制得中间体5-乙酰胺甲基-3-[3-氟-4-(4-氯乙酰基-1-哌嗪基苯基)]异噁唑啉(2);2与取代哌嗪或取代六氢吡啶反应合成了15个新型的异噁唑类衍生物(4a～4o),其结构经1H NMR和FAB-MS表征。初步的生物活性测试结果表明,4a～4o对金黄色葡萄球菌、藤黄八叠球菌、绿脓假单胞菌和肺炎克雷伯杆菌均有一定的抗菌活性。     

A green,simple, catalyst-free,and efficient method for electro-organic synthesis of new benzofuran derivatives

In this work, the electrochemical oxidation of catechols 1a and 1b was studied in the presence of pyrazolidine-3,5-dione (3a), as a nucleophile, in a mixture of ethanol and a phosphate buffer solution (0.1 M, pH 7), as a green medium, using the cyclic voltammetry and controlled-potential coulometry techniques. The results obtained indicated that the oxidized forms of these catechols (2a and 2b) participated in the Michael addition reactions with pyrazolidine-3,5-dione (3a), and converted, via an ECEC mechanism, to their corresponding benzofurans (7a and 7b). In this work, some new benzofuran derivatives were synthesized with good yields and high purities using a facile, one-pot, and environmentally friendly electrochemical method in the absence of any chemical catalyst, toxic solvent, and hard conditions.     

A simple and efficient method for the synthesis of Erlenmeyer azlactones

We have recently developed a novel and efficient method for synthesising Erlenmeyer azlactones under mild and rapid conditions. The reaction is performed by reacting 2-phenyl-5-oxazolone with an aldehyde in dichloromethane using alumina as a catalyst. The materials react instantly at room temperature, negating the need for high temperatures and long reaction times. We have successfully used this method for both aliphatic, aromatic and heteroaromatic aldehydes, synthesising previously unmade Erlenmeyer azlactones in moderate to high yields.     

A simple and efficient procedure for the synthesis of optically active s-triazolothiadiazole derivatives

A series of novel s-triazolothiadiazoles 3a-h were prepared by condensation reaction of substituted amino triazoles la-b with N-phethaloyl-L-amino acids 2a-d in the presence of the phosphoroxy chloride（POCl₃） as an anhydrous reagent.The structure of all synthesized compounds was confirmed by IR,¹H NMR,and ¹³C NMR spectroscopy.     

A convenient method for efficient synthesis of isoxazole-containing thiadiazepine derivatives

Chemistry of Heterocyclic Compounds - An effective strategy has been developed for the preparation of isoxazole-containing thiadiazepine derivatives via the reaction of 1,3-diallyl sulfamide with...     

A simple and efficient synthesis of 3-substituted derivatives of pentane-2,4-dione

A novel and efficient method of synthesis of 3-substituted derivatives of pentane-2,4-dione is proposed, wherein cheaper and easily accessible chloro derivatives are conversed into more reactive iodo derivatives. The method is based on the Finkelstein reaction for which the literature suggests highly polar organic solvents as ideal reaction media. In the presented work, the use of industrially used ketones, especially methyl isobutyl ketone, is proposed. The use of MIBK as a solvent additionally allows an azeotropic removal of water from the reaction mixture, enabling the application of moisture sensitive alkylating agents i.e. (3-chloropropyl)trimethoxysilane. The obtained products are isolated through distillation, which does however not allow the separation of C-alkylation products from O-alkylation ones. The products not containing water-sensitive substituents were isolated as copper complexes. The pure product of C-alkylation was obtained by decomposition of the copper complex with a hydrochloric acid solution and extraction of the formed ligand to an organic phase i.e. hexane. The obtained ligand can be further purified by distillation. Presented at the 35th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 26–30 May 2008.     

ZnO-beta zeolite mediated simple and efficient method for the one-pot synthesis of quinoxaline derivatives at room temperature

A rapid and an efficient one-pot method for the synthesis of quinoxalines catalysed by ZnO-beta zeolite at room temperature is described. This environmentally benign method provides several advantages over methods that are currently employed such as a simple work-up, mild reaction conditions, good to excellent yields, and a process to recover and reuse the catalyst for several cycles with consistent activity.      

A simple and efficient method for synthesis of fluorine-containing saccharide esters and antiviral activity

Sixteen new fluorine-containing saccharide esters from fluorine-containing benzoic acids and α-O-acetylglycosyl bromide were synthesized in the presence of 4-dimethylaminopyridine (DMAP) and triethylamine (Et₃N) under mild conditions in good yields and their structures were clearly verified by IR, ¹H NMR, MS and elemental analysis. This method has high stereospecificity, the configuration is unitary, the new synthesized compounds are all of β-configuration. The results of bioassay showed that these title compounds possess potential antiviral activities against tobacco mosaic virus (TMV).     

A simple and efficient method for regioselective and stereoselective synthesis of vicinal bromohydrins and alkoxybromides from an olefin

A very rapid and efficient method has been developed for the synthesis of vicinal bromohydrins and alkoxybromides directly from an olefin without any catalyst. The reaction was performed in CH3CN-water (4:1) or alcohol using N,N-dibromo-p-toluenesulfonamide (TsNBr2) as the brominating agent. Excellent yields and regio- and stereoselectivities have been obtained. Bromohydrins are formed instantaneously, whereas formation of alkoxybromides takes 30-60 min.     

A simple and highly efficient method for the synthesis of chalcones by using borontrifluoride-etherate

Chalcones are secondary metabolites of terrestrial plants, precursors for the biosynthesis of flavonoids and exhibit various biological activities. Condensation of substituted acetophenones (2a-12a) with various aromatic aldehydes (1b-7b) in the presence of BF₃-Et₂O at room temperature gave chalcones in 75-96% yield.