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THE FIRST TOTAL SYNTHESIS OF TAXAMAIRIN B Taxamairin B, representive of rare naturally-occuring rearrang-ed 9(10→20)-abeo-8, 11, 13-triene diterpenoids, has been firstsynthesized by a eleven-step route in an overall yield of 8.19%,starting from commercially available catechol and 1,3-cyclohexan-dione. The improved Friedel-Crafts annulation, thermodynamicallycontrolled-geminal pairing methylation, the selective oxidation ofallyl group and the selective reduction of the less-hindrancecarbon-carbon double bond are the key steps.

二。美丽红豆杉素B的全合成研究 1,美丽红豆杉素B的首次全合成以价廉,易得的邻苯二酚和1,3-环己二酮为原料,经过改良的Friedel-Crafts烷基化反应,热力学控制的α,β-不饱和酮结构的α一位双烷基化,烯丙位的选择性氧化,以及选择性还原位阻较小的碳碳双键等十一步反应,以8.19%的总收率首次完成了美丽红豆杉素B的全合成。

After that, we introduced a new approach to synthesis of valiolamine, by a series of reaction to the carbon-carbon double bond from the substrate of valienamine, including epoxidation, hydrogenolysis and so on, and obtained the aim product finally.

在完成上述合成路线后,本文通过提出了一条全新的合成伏格列波糖重要中间体valiolamine的路线,即采用对底物valienamine中的碳-碳双键进行环氧化、氢解等一系列反应,成功地制备出所需的中间体,研究全新的合成伏格列波糖的路线,研究结果证实:该新路线已经被打通。

Purine: Any of a class of heterocyclic compounds with a two-ring structure compose d of carbon and nitrogen atoms.

嘌呤:嘌呤是对由碳、氮原子组成的双环结构的杂环化合物的统称。

By using the a device being similar to water segregator and by controlling the temperature, cyclization of the intermediate product in chloroform reduced carbonization and gave 2-dodecaneanthraquinane in 68.1% yielding.

以十二烷基苯和苯酐为起始原料,经酰基化、关环和磺化三步反应合成了3-十二烷基蒽醌磺酸;并进一步改进和优化了合成工艺条件:即在催化剂三氯化铝过量50%并有三乙胺存在的条件下,中间体2-(4-十二烷基苯甲酰基)苯甲酸收率为72.45%;关环反应采用氯仿作溶剂,利用类似分水器的装置有效控制反应温度以减少碳化,2-十二烷基蒽醌的收率为68.1%。

Quinazolin-4(3H)-ones(1) were conveniently synthesized from anthranilic acids and amidines,which could be chloridized with POCl_3 to obtain 4-chloroquinazolines (2).The reaction of 2 and 1H-pyrazol-3-amine would give two types of products.In the presence of acid or base,the C-N bond would be formed between the 4-position carbon of 2 and the NH_2 of 1H-pyrazol-3-amine.While the C-N bond between the 4-position carbon of 2 and the NH of 1H-pyrazol-3-amine would be formed when Pd catalyst was utilized.

以邻氨基苯甲酸类化合物和脒为原料,可方便地获得喹唑啉-4(3H)-酮类产物(1),1经POCl_3氯化可到4-氯代喹唑啉化合物(2)。2与3-氨基-1H-吡唑化合物反应可得到两种类型的产物,在酸、碱条件下2的4位碳和3-氨基-1H-吡唑化合物的NH_2发生C-N成键反应;在Pd催化条件下,2的4位碳则和3-氨基-1H-吡唑化合物的环内NH发生C-N成键反应。

The selectivity of cyclization of carbodiimide 2 with primary amine was studied and the result showed that the anomalous product being cyclized from arylamino group was formed preferencially.

研究了碳二亚胺2与伯胺成环反应的选择性,结果表明优先生成反常的芳氨基成环产物,利用中间体可能的构型解释了实验结果。

This is probably due to the geometry of the intermediate. 3. The cyclization of carbodiimide 2 with 1H-1, 2, 4-triazole in presence of solid potassium carbonate was studied firstly. The interesting color change was observed during the reaction process. The condition for cyclization was researched.

首次研究了碳二亚胺2与1H-1,2,4-三唑在固体碳酸钾存在下的成环反应,结果表明该反应仅生成1-N产物,而且在反应过程中出现了有趣的颜色变化,研究了该成环反应的条件。

Their adsorption rate on the molecular sieve catalysts surface and the stability of their carbonium ions were then obtained based on the molecular simulation on these molecules from their dipole moment, 2-dimensional electrostatic potential energy contours and 3-dimensional electrostatic potential energy isosurface.

采用半经验的AM1量子化学计算方法和静态理论,分别考察了噻吩、 3 甲基噻吩和 2 ,5 二甲基噻吩分子结构特性的不同,从偶极矩、各自垂直于芳香环平面的二维电势能分布曲线和整个分子周围三维电势能分布情况等方面分析了它们在分子筛催化剂表面吸附速度的快慢和生成正碳离子稳定性的高低,进一步比较了噻吩及其衍生物所生成的正碳离子进一步反应的能量变化,从而可判断噻吩及其衍生物裂化脱硫速度的快慢,噻吩及其衍生物裂化脱硫的速度由大到小分别为:2 ,5 二甲基噻吩、 3 甲基噻吩、噻吩。

SM6 and SM7 of uncrystal were analyzed through GC-MS, the results showedthat SM6 main contained unsaturated fatty aldehyde with fragrance, i.e.-2,4-decadienal(58%), tetradecanoic acid (55.78%), 2-decenal(50%), Phthalic acid isobutylundecyl ester(47%), 2, 4-Decadienal(41%), 2-Undecenal (31%), 2-Methyl-Z,Z-3, 13-octadecadi-enol(18.84%), and SM7 contained saturation alkanes, i.e. 1, 2-Benzenedicarboxylic acid, butyl cyclohexyl ester(23.90%), Triacontane(22.63%),Nonacosane(21.04%), Heptadecane(18.84%), Octacosane(13.58%). Toxicological experiments were done to insure the pigment safety.

并对紫红丝膜菌色素非晶体部分的黄色油状物SM6和紫色粉末物SM7作了GC-MS分析,结果显示SM6中主要为具有香气成分的不饱和脂肪醛,其中含量较高的依次为:-2,4-癸二烯醛(58%)、十四烷酸(55.78%)、2-癸烯醛(50%)、邻苯二甲酸异丁基十一烷酯(47%)、2,4-癸二烯(41%)、2-十一碳烯醛(31%)、2-甲基-Z,Z-3,13-十八碳二烯酸(18.45%)等;SM7中主要为饱和直链烷烃,其中含量较高的依次为:1,2-苯二羧酸丁基环己酯(23.90%)、三十烷(22.63%)、二十九烷(21.04%)、十七烷(18.84%)、二十八烷(13.58%)。

Seven of them have not been reported.Their structures were confirmed by IR,~1HNMR,MS,and element analysis. 4.Meanwhile,the green methylation procedure of imides was developed by using dimethyl carbonate as methylation reagent.A series of imides,for example,phthalimide,3,4-dibromo-maleimide and succincide were used for substrates.The effects of DABCO(1,4-diazabicyclo [2.2.2]octane)and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)as a catalyst in this kind of reactions were investigated.2-Bromo-3-(1-methylindolyl-3-yl)-1-methyl-1H-pyrrole-2,5-dione was prepared by using dimethyl carbonate,which further expanded the use of dimethyl carbonate,as a green agent in organic synthesis.

在以硫酸二甲酯为甲基化试剂对3,4-二溴马来酰亚胺进行N-甲基化反应合成3,4-二溴-N-甲基马来酰亚胺的同时,以碳酸二甲酯为甲基化试剂,对3,4-二溴马来酰亚胺、邻苯二甲酰亚胺、琥珀酰亚胺等酰亚胺类化合物的N-甲基化反应进行了研究;考察了1,4-二氮杂双环[2.2.2]辛烷,1,8-二氮杂双环[5.4.0]十一碳-7-烯、碳酸钾和四丁基溴化铵等作为催化剂对碳酸二甲酯N-甲基化反应的反应时间和收率等的影响,并应用碳酸二甲酯为甲基化试剂,合成了N-甲基-3-溴-4-(1-甲基-吲哚-3)-马来酰亚胺。

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The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应,而且减少跟风的可能性。

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