四苯呋喃

IV. The total synthesis of dehydrodiconiferyl alcohol and its dihydro-derivative The benzofuran skeleton was constructed by chemically oxidative couplingstarting from vanillin, then selective reduction with LiAI〓/〓 andhydrogenation in the presence of Pd-C followed reduction with LiAl〓respectively, to give dehydrodiconideryl alcohol and its dihydro-derivative, usefulin treating and preventing digestive system disorders, esp.

四、Dehydrodiconiferyl alcohol及其二氢衍生物的全合成以香草醛为起始原料，用化学氧化法一步建立氢化苯骈呋喃骨架，LiAlH〓／〓选择性还原以及催化加氢还原接着〓还原，分别合成了对预防和治疗消化系统疾病尤其是胃溃疡有显著效果的Dehydrodiconiferylalcohol及其二氢衍生物。

Maleic Anhydride is important organic raw material and the third biggest acid anhydride next to benzene anhydride and acid anhydride. In recent years, Maleic Anhydride is esterified and hydrogenised under pressure to make 1,4- butanediol butylene glycol, and it is also hydrogenised to tetrahydrofuran, which enables Maleic Anhydride to become the raw material for producing high-value-added products and to be more widely applied.

顺酐是重要的基本有机原料，也是世界上仅次于酸酐和苯酐的第三大酸酐，近年来，顺酐脂化低压加氢制1.4-丁二醇和顺酐加氢制四氢呋喃技术的开发成功，是顺酐成为生产高附加值产品的原料，应用领域有了更进一步的拓展。

The reducing-coupling reaction of benzoyl chloride under Dy/n-BuBr was complex. Besides diphenyl diketone, benzoin and ring-opening product of THF were also obtained.

苯甲酰氯在Dy/n-BuBr作用下的还原偶联反应较为复杂，除得到二苯基乙二酮外，还得到四氢呋喃开环产物以及安息香。

An unstable important intermediate ,2- methoxymethyl-hydroquinone which is very easy to oxidize and polymerize, and its precursors were first synthesized, a...

第一、二条合成线路前人未见报导，从中得到了四个苯并呋喃类衍生物，并详细地探索了环化反应的条件。

Business company dispatch home was mixed first sets with suitable anhydride on July 8 hydric produce for raw material 1, 4- Ding Erchun (4 hydrogen of BDO)/ furan introduce device to finish function to assess, the mark is worn this technology realized success application in our country.

生意社7月8日讯国内首套以偏苯三酸酐和氢气为原料生产1，4-丁二醇/四氢呋喃的引进装置完成性能考核，标志着该技术在我国实现了成功应用。

The unit can be used to sample most containerized liquid wastes, except those containing ketones, nitrobenzene, dimethylformamide, mesityl oxide, and tetrahydrofuran.

该装置可用于大部分的废品样本采集除含有酮，硝基苯，二甲基甲酰胺，异丙叉丙酮和四氢呋喃的液体废品。

In this work,the new kind of polyurethane have been prepared from Bis(4—β—hydroxyphnyl)sulphone,polyhydrofuran, 4,4′—di—phenylmethane diisocyanate,by one—step reaction metho -d and block copolymerizatiano.

本文用一步反应法，由双(4-β-羟基乙氧基苯)砜，聚四氢呋喃，4，4′—双苯基甲烷二异氰酸，采用嵌段共聚法，制成了一种新型聚氨酯。

Synthesis of the antiepileptic tiagabine hydrochloride;2. Starting from tetrafuran, 2_(4_Aminosulfonylphenyl)_4H_1,2_thiazine_1_dioxide, an antiepileptic drug with special structure, was obtained via esterification, sulphonation, chloridization, condensation and cyclization.

以四氢呋喃为原料，经酯化、磺化、酰氯化、缩合、环化等步骤，合成了化学名为 4_(四氢_2H_1，2_噻嗪基_2 )苯磺酰胺_S_S_二氧化物的抗癫痫药舒噻嗪，通过IR、1HNMR和元素分析对其结构进行了表

Unoxidated and oxidized wheat stalks were extracted sequentially with CS2, benzene, methanol, acetone and THF, and the extraction solutions were analyzed with GC/MS. The relative contents and compositions of fractional extracts of un-oxidized and oxidized wheat stalks were compared.

采用二硫化碳、苯、甲醇、丙酮和四氢呋喃对未氧化和氧化的麦秆进行分级萃取，比较麦秆各级萃取物的相对含量和组成差异，并对各级萃取物的组成进行GC/MS分析。

The UV and MS qualitative analysis of the eluates in different eluting time showed that the aromatics were basically separated by the Ag-SCX column according to the number of aromatics rings.

实验发现，流动相中的水含量直接影响Ag-SCX柱的活性，严格控制流动相中的含水量可将色谱柱的活性稳定在一定水平，失活后的色谱柱经1：1的苯／四氢呋喃冲洗几个小时后即可恢复其活性。

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。