查询词典 acetylenic

Results showed that the alkynol compounds were transformed to the corresponding alkyne aldehyde and acetylenic acid compounds containing conjugated system on the nickel anode, and hence the anodic oxidation reaction products were able to generate ultraviolet absorption.

结果表明，炔醇类化合物在阳极生成了相应的有共扼体系的炔醛类和炔酸类化合物，产生了紫外吸收。

Calcium carbide production, dissolved acetylene, self-diol, has been acetylenic diol, a hybroxybutyric alcohol, methyl amyl alcohol, without the others methyl diol and other products.

主要生产碳化钙、溶解乙炔、己二醇、己炔二醇、甲基丁炔醇、甲基戊炔醇、不带甲基的己二醇等产品。

Effect of tazarotene, an acetylenic retinoid, on human dermal fibroblast［J］.

维甲酸对人角膜基质细胞增殖和移行的影响［J］。

Acetylenic ketone promise physiological performance is the human body generated by the first body progesterone ketones 4-8 times.

炔诺言酮的生理效能是人体内产生的孕激素首体酮的4-8倍。

Second,so called industrial fatty acids,which usually contain functional groups such as hydroxyl,epoxy,or acetylenic bonds,are important industrial ...

本文综述了近年来几种特殊脂肪酸生物合成的基因工程研究进展。

In chapter three,we investigated a new Baylis-Hillman-type reaction,organozinc speciesCF_3COOZnEt can react withα,β-acetylenic ketones and N-tosylated imines providing Baylis-Hillman adducts in good yield in the absence of any catalysts.

有机锌试剂CF_3COOZnEt可以与各种类型的α，β-炔酮及亚胺发生偶联反应，高产率的得到β-取代的Morita-Baylis-Hillman反应加合物，这类反应不需要任何的催化剂，产物具有立体单一型，完全是Z式结构。

The invention discloses a process for preparing N-Boc derivative or N-Cbz derivative of chiral alpha, alpha'-double substituent pyrrolidine which contains ethylenic link and acetylenic link substituent.

本发明公开了一种制备含烯键和炔键取代基的手性α，α'-二取代吡咯烷的N-Boc衍生物或N-Cbz衍生物的方法。

Organozinc reagents can react with a variety of α,β-acetylenic ketones and aldehydes in the absence of any catalyst. The one-pot reaction affords β-branched Baylis-Hillman type adducts, the multifunctionalized alkenes, in excellent yields with high stereoselectivity.

这种顺式亲核加成反应的发生是由于该类有机锌试剂既具有较强的亲核性，又具有Lewis酸的特性，使有机锌中R基团从同位进攻中心碳原子而形成新的碳碳键。

The E-TOF will also be feasible and practical to assist chemists in screening the optimal reaction condition or evaluating the overall efficiency of different catalytic systems for a specific asymmetric reaction.4.For the first time,we explored chiralγ-hydroxy-α,β-acetylenic esters,which were prepared via asymmetric alkynylation,as key intermediates to the synthesis of chiralγ-butyrolactones. This convergent and enantioselective approach to chiralγ-butyrolactones is practical and easily handled with protecting group free.

这一概念包括反应产率、对映选择性、配体用量以及反应时间四个重要反应参数，不仅适用同一反应不同催化体系的横向综合性评价，而且适用于某一特定反应催化体系的优化过程，有助于研究人员选择最佳的反应条件。4、我们发展了以手性γ-羟基-α，β-炔酸酯为关键中间体完成了手性γ-丁内酯类天然产物的对映立体选择性全合成，该关键中间体能够以我们的催化体系方便的对映选择性合成，之后的官能团转换方法成熟，易于操作，无需进行繁琐的官能团保护和脱保护过程，绿色经济。

With 1,2-dimethoxyethaneas an additive,the reaction proceeded under mild condition to gave the highly functionalizedγ-hydroxy-α,β-acetylenic esters,and highly toxic reagent was avoided.

以DME为添加剂使不对称合成手性γ-羟基-α，β-炔酸酯的反应条件更加温和、易于操作，避免了剧毒物质的使用。

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。