立体异构
- 与 立体异构 相关的网络例句 [注:此内容来源于网络,仅供参考]
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The present invention concerns a compound having the formula a N-oxide form, a stereochemical isomer, racemic mixture, salt prodrug, ester or metabolite thereof.
本发明涉及具有式的化合物、其N-氧化物形式、立体化学异构体、外消旋混合物、盐、前体药物、酯或代谢物。
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The behavior of o-isometer is special and complicated compared to the other two isometers due to its steric effect.
邻位取代的异构体行为比较特殊,变化规律比较复杂,这主要归因于邻位的空间立体效应。
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The results showed that the addition leading to -2-phenyl-2-(2-vinylpiperidin-1-yl) ethanol 7 could proceed with good diastereoselectivity and excellent yield (95%).(3) The selective N-deprotection of -2-phenyl-2-(2-vinylpiperidin-1-yl) ethanol 2 without affecting the vinyl group in the substrate were untaken.(4) The Zip reaction for the transformation of -1-(3-aminopropyl)-3-methylazecan-2-one 8 to -7-Methyl-1, Sdiaza-cyclotetradecan-6-one 9 were undertaken. The results showed that, under controlled conditions, acceptable yields (43%) could be achieved and racemization can be minimized during the ring expansion reaction.
该合成路线与文献方法相比,反应条件较温和,也缩短了反应时间;(2)哌啶衍生物2与乙烯基格氏试剂进行加成反应的条件和立体选择性,取得了较好的结果(差向异构体比为80:20,产率95%左右);(3)不饱和哌啶衍生物7在不影响碳碳双键的情况下去除苯基甘氨醇手性辅助基的条件;(4)具有羰基α位手性的氨基酰胺8在不同条件下经Zip重排反应转变为9的反应,控制反应条件,可使反应中消旋化减小到最小的程度。
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This Sm-catalyzed reaction firstly efficiently realized the catalytic cycle in the tandem rearrangement/reduction reaction of α-hydroxy epoxides, and moreover the diastereoselective amplification could be distinctly observed when two C1 epimers in substrate were subjected to this catalytic tandem reaction.
该催化的多功能串联反应,高度非对映选择性地一步控制了含有季碳的三个相邻立体中心,有效地构建了&2-季碳1,3-二醇&结构单元,首次实现了此类重排—还原过程的催化循环,其中对于两个C1位的差向异构体底物,此反应具有明显的非对映选择性放大特点。
- 推荐网络例句
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It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.
从鲍尔点的形成原理出发,分析对称连杆曲线上鲍尔点的产生条件,提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。
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The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.
集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品,年生产总值3000万美元,产品价廉物美、选料上乘、质量保证,深受国内外客户的青睐
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The eˉtiology of hemospermia is complicate,but almost of hemospermia are benign.
血精的原因很,以良性病变为主。