环戊烯

The cytotoxicity of these compounds were valuated by MTT and SRB methods using three cancer cell lines: HL-60, A-549, P-388. Cyclo-shikonin, and cyclo-alkannin have high cytotoxicity against HL-60.The chiral center of side chain has no effect on their activity. 2- 1-(Acetyloxy-4-methyl-3-pentenyl -5, 8-dihydroxy-1, 4-naphthoquinone (105) has strong inhibition effect on P-388 cells. 2- 1-(isooctyloxy-4-methyl-3-pentenyl -5, 8-dihydroxy-1, 4-naphthoquinone (108) and 2- 1-(2-furoyloxy-4-methyl-3-pentenyl -5, 8-dihydroxy-1, 4-naphthoquinone (112) have high inhibition on A-549.Shikonin (1), alkannin (2), and their derivatives have the structural features of a planar chromophores and short side chain. We examined the ability to inhibit the telomerase.

抗肿瘤活性初步筛选测试采用小鼠白血病P-388肿瘤细胞和人肺癌A-549肿瘤细胞进行，结果表明侧链羟基的手性对抗肿瘤活性无明显影响；有数个化合物具有很好的体外抑制活性，特别是化合物2-（1-异辛酰氧基-4-甲基-3-戊烯基）-5，8-二羟基-1，4-萘醌（108）和2-[1-（2-呋喃甲酰氧基）-4-甲基-3-戊烯基]-5，8-二羟基-1，4-萘醌（112）体外显示对人肺癌A-549肿瘤细胞有强效；2-（1-乙酰氧基-4-甲基-3-戊烯基）-5，8-二羟基-1，4-萘醌（105）对小鼠白血病P-388肿瘤细胞有强效；环紫草素和环异紫草素对人白血病HL-60细胞有强烈抑制作用。

Atherosclerosis: a redox-sensitive lipid imbalance suppressible by cyclopentenone prostaglandins.

动脉粥样硬化：环戊烯酮前列腺素抑制氧化还原敏感的脂质失衡

So, by the Diels-Alder reaction of tetraphenylcyclopentadienone, acenaphthenecyclone and benzophenanthrenecyclone with the vinyl groups in C gum, three kinds of polymethylvinylsilicone oil with condensed aromatics are synthesized respectively: polymethylvinylsilicone oil with tetraphenylphenyl groups (called C_1 gum for short), polymethylvinylsilicone oil with acenaphthenyl groups (C_2 gum) and polymethylvinylsilicone oil with benzophenanthrene groups (C3 gum).

根据此原则，利用四苯基环戊二烯酮、苊式环戊二烯酮和菲式环戊二烯酮与C胶上的乙烯基进行Diels—Alder反应，分别合成了三种含稠环基团的乙烯基硅油：四苯基苯基乙烯基硅油(C_1胶)，苊式多苯基苯基乙烯基硅油(C_2胶)和菲式多苯基苯基乙烯基硅油(C_3胶)，并根据~1HNMR谱图上不同氢原子的积分面积计算了三种胶中稠环基团和乙烯基的含量。

The preparation method of cyclopentadiene from bicyclopentadiene with liquid phase thermal decomposition method is studied.

研究了采用液相热分解法由双环戊二烯制备环戊二烯的实验条件。该法操作简单，环戊二烯纯度达95%，收率可达85

The preparation method of cyclopentadiene from bicyclopentadiene with liquid phase thermal decomposition method is studied.

研究了采用液相热分解法由双环戊二烯制取环戊二烯的方法。该法操作简单，连续化。环戊二烯纯度达98％－99％，收率85

Present status and application of isoprene,cyclopentadiene and m-pentadiene in cracking C_5 fraction products were reviewed.

重点介绍了国内外裂解C5分离产物异戊二烯、环戊二烯和间戊二烯利用近况，提出C5综合利用具有很广阔的发展前景和现实意义。

The main compositions of LP are shorter chain carboxylic acid and their ethyl esters, furan derivatives, cyclopentanone, phenol derivatives, benzene derivatives, aromatic ketone, aromatic acid derivatives, longer chain carboxylic ethyl esters and sterides. After upgrading, the main indexes reach the standard of fuel oil.

结果表明，LP的主要成分包括短链或环状脂肪酸及其酯、呋喃衍生物、环戊烯衍生物、苯酚衍生物、苯衍生物、芳酮、芳酸及其乙酯、长链脂肪酸乙酯和甾族化合物，经提质其主要指标达到了燃料油的标准。

Firstly, dicyclopentyldichlorosilane, a reaction intermediate, was prepared under the optimal conditions of a reaction pressure range of 1.0-1.2 MPa, a n/n of 1.16, a reaction temperature range of 85-95℃, a catalyst dosage of 1.2 g, an isooctyl alcohol dosage of 2.3 g and a reaction time range of 6-7 h. The conversion of cyclopentene and the yield of DCPDCS were 96.2% and 88.9%, respectively.

首先研究了合成DCPDCS的最佳工艺条件：反应压力1.0~1.2 MPa，n/n= 1.16/1.00，反应温度85~95 C，催化剂用量1.2 g，异辛醇用量2.3 g，反应时间6~7 h，环戊烯转化率可达96%以上，DCPDCS收率可达88%以上。

The application markets of three kinds of isoolefines(isoprene, cyclopentadiene ,piperylene) from the cracking C5 fractions and their downstream derivatives were reviewed.

着重评述了裂解C5馏分资源中3种异构烯烃(异戊二烯、环戊二烯和间戊二烯)及其下游衍生物的应用市场，并剖析了我国裂解C5资源的利用现状及应用前景。

This dissertation is concerned with the approaches to a new high density liquid fuel , tetrahydrotricyclopentadiene, which can be synthesized with dicyclopentadiene as raw materials by three steps: Diels-Alder reaction, separation and hydrogenation.

本文以双环戊二烯为原料，通过双烯加成、分离、加氢反应得到目的产物——新型高密度液体燃料四氢三环戊二烯，主要研究内容包括： 1。三环戊二烯的合成采用两种方式对TCPD的合成进行了研究：DCPD直接热聚法、DCPD与环戊二烯双烯加成法。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失