N7-鸟嘌呤烷化物的合成及其在DNA损伤检测中的应用

以2′-脱氧鸟苷为原料,经亲电取代反应,合成了五个Ⅳ7-位鸟嘌呤烷化物—N7-(2-羟乙基)鸟嘌呤、N7-(2-氯乙基)鸟嘌呤、N7-(2-溴乙基)鸟嘌呤、N7-乙基鸟嘌呤和N7-烯丙基鸟嘌呤,其结构经UV,1H NMR,IR和MS确证.以N7-(2-羟乙基)鸟嘌呤和N7-(2-氯乙基)鸟嘌呤为标准品,采用HPLC-MS对1,3-双(2-氯乙基)-1-亚硝基脲(卡莫司汀)导致DNA烷化损伤产物进行了分析.     

水溶性葛根素衍生物的合成

以葛根素为起始原料,分别经亲核取代反应和羟甲基化反应得到水溶性4′-羟乙基葛根素和3′,5′-二羟甲基葛根素,对首次得到的3′,5′-二羟甲基葛根素,用正交实验对的合成条件进行了优化,当n(葛根素)∶n(甲醛)∶n(氢氧化钠)=1∶2∶4,反应温度为60℃,反应时间为4.0 h,产率为69.0%。目标化合物的结构经IR、~1H NMR、~(13)C NMR和元素分析方法进行表征。经测试4′-羟乙基葛根素和3′,5′-二羟甲基葛根素水溶性分别是葛根素的5倍和10倍。     

氟伐他汀钠的合成

以氟苯为起始原料,通过两步反应得N-(4-氟苯甲酰甲基)-N-(1-甲基乙基)苯胺(5);5在ZnCl2存在下环化得3-(4′-氟苯基)-1-(1′-甲基乙基)吲哚(6);6与3-N-甲基-N-苯基胺基丙烯醛发生Vilsmeier-Haauc反应得(E)-3-[3′-(4″-氟苯基)-1′-(1″-甲基乙基)吲哚-2′-基]-2-丙烯醛(8);8经缩合、还原、水解得氟伐他汀钠,总收率10.5%.     

N-(4,6-二取代嘧啶-2-基)-N′-(1-甲基-3-乙基-4-氯吡唑-5-基)甲酰基(硫)脲的合成及生物活性

利用活性结构拼接原理,将高效杀螨剂吡螨胺分子的吡唑环部分引入酰基(硫)脲化合物中,以1-甲基-3-乙基-4-氯-5-甲酸基吡唑和2-氨基-4,6-二取代嘧啶为起始原料,通过多步反应合成了5种N-(4,6-二取代嘧啶-2-基)-N′-(1-甲基-3-乙基-4-氯吡唑-5-基)甲酰基脲和5个N-(4,6-二取代嘧啶-2-基)-N′-(1-甲基-3-乙基-4-氯吡唑-5-基)甲酰基硫脲化合物,其化合物结构经IR、1HNMR及元素分析测试技术确证。初步生物活性试验表明,在50mg/L质量浓度下目标化合物的杀螨活性不太理想,但有些化合物具有较好的除草活性,其中化合物Ⅰb、Ⅰc和Ⅰe对稗草主根的生长抑制率大于60%。     

香豆素类Schiff碱的合成

以乙酸和哌啶为催化剂,在正丁醇中通过4-(N,N-二乙氨基)水杨醛与硝基乙酸乙酯的缩合反应合成了3-硝基-7-(N,N-二乙基)香豆素(2);2经SnCl2/HCl还原制得3-氨基-7-(N,N-二乙基)香豆素(3);3与芳香醛反应合成了六个新的香豆素类Schiff碱,其结构经UV,1H NMR和MS表征.     

手性叔胺脲催化靛红亚胺与苯胺的不对称aza-Mannich反应

报道了Takemoto型手性(硫)脲催化靛红亚胺与苯胺的不对称aza-Mannich反应。在0.1 mmol反应量下,筛选出最佳催化剂体系为：10 mol%催化剂N-[3,5-二(三氟甲基)苯基]-N′-[(1S,2S)-2-(二甲氨基)环己基]脲1d,1 mL乙醚,0℃反应。以71～82%的收率和最高达97%ee获得系列手性3-N,N′-靛红缩酮。     

5-(N-2-羟乙基)羟乙酰氨基-N,N′-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺的合成

5-氨基-N,N′-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺(2)在N,N-二甲基乙酰胺中可直接与乙酰氧基乙酰氯反应,产物再经碱性水解得5-羟乙酰氨基-N,N′-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺(3),后者再与氯乙醇反应生成5-(N-2-羟乙基)羟乙酰胺基-N,N′-双(2,3-二羟丙基)-2,4,6-三碘-1,3-苯二甲酰胺(1),经乙二醇甲醚/正丁醇重结晶,纯度高于99%(HPLC),反应总收率由39.3%(文献值)提高到55.1%.     

2-甲基-3-双取代基-4,5-二氢异噁唑衍生物的合成及其拆分

3-(1′,2′-二-O-环己叉二氧乙基)异噁唑啉盐(2)与MeMgBr(或在二异丙基胺和正丁基锂存在下与乙酸乙酯)进行亲核加成反应合成了2,3-二甲基-3-(1′,2′-二-O-环己叉二氧乙基)-4,5-二氢异噁唑(3)[或2-甲基-3-(乙氧羰甲基)-3-(1′,2′-二-O-环己叉二氧乙基)-4,5-二氢异噁唑(4)]。3和4经MPLC拆分得到了非对映体3a,3b,4a和4b,其结构经1HNMR,13C-NMR,IR和元素分析表征。     

稀土穴状荧光配合物的合成与光谱性质

以2,6-二甲基吡啶-3,5-二甲酸二乙酯为起始原料,经N-溴代丁二酰亚胺(NBS)溴代、亲电取代反应合成了时间分辨荧光免疫分析双功能螯合剂2,6-{N,N′,N,N′-[二(2,2′-联吡啶-6,6′-二甲基)]二(氨甲基)}-吡啶-3,5-二羧酸二乙酯。经差热分析仪(DTA)、傅里叶变换红外光谱仪(FTIR)、核磁共振波谱仪(1 H NMR)、质谱仪(MS)等技术手段表征确认了化合物结构和性能。对该化合物与铕离子形成螯合物的荧光性质研究表明:激发光谱波长范围较宽,激发峰值为322nm;荧光发射峰为597nm(~5D_0-~7F_1)、618nm(~5D_0-~7F_2);荧光寿命为918μs;量子产率Φ=0.249。     

微波促进下邪蒿素及其衍生物的合成

以取代7-(1,1-二甲基-2-炔丙氧基)香豆素(4a～4h)为原料,经微波反应合成了8个邪蒿素类似物(1a～1h).优化的微波合成条件为200℃、5～10min、以N.甲基甲酰胺(NMF)或N,N-二乙基苯胺(DEA)为溶剂.该微波反应具有反应完全(转化率＞98%)、区域选择性高(角型/线型产物比为9:1)和产率明显高于传统的Claisen重排反应的优点.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

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%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

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.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

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.