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The efficient first asymmetric syntheses of-6β-hydroxy-7αH-eudesm-4-en-3-one, and its C-6 epimer were achieved starting from-dihydrocarvone, whichprovide a novel and efficient synthetic method to 6-oxgenated eudesmanes.
以-二氢香芹酮为原料，经五步反应，首次完成了6β-羟基-4(5)-烯-3-羰基桉烷及其6位差向异构体的立体选择合成，并为C-6位含氧官能团取代桉烷类化合物的合成提供了一种简便有效的方法。
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In conclusion, a catechol moiety is presumably to be essential for its activity and substitution of the p-hydroxybenzyl group at C-1 position with correct stereochemistry in the isoquinoline molecule makes a great contribution to the activation of beta adrenergic receptors.
本实验初步结果发现，对於去甲基乌药碱分子之药效，catechol基是必备无疑；而异喹啉环的碳－1位置上取代的p-hydroxybenzyl基对於药效有非常大的影响；至於其立体化学的配位是有立体选择性的。
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Nevertheless, the yield of pinacol was also strongly affected by the steric environment surrounding the carbonyl group. The pinacol coupling of aromatic aldehydes has been achieved with high yields under such a condition. However, the diastereose-lectivities of pinacols were not satisfying. Unfortunately, the ketones and most aliphatic aldehydes appeared inert under the same reaction conditions.
然而， 呐偶合反应的产率受到羰基周围环境的立体位阻影响较大，在此条件下，锌粉能有效地促进芳香族醛类化合物进行水相呐偶合反应，得到的呐醇产率高，但非对映异构体选择性差，而脂肪族醛类化合物得到的呐醇产率较低，在同样的条件下，酮类化合物不能顺利进行呐偶合反应。
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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。
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isomerism：异构
配合物基础和配位立体化学配合物(complexes)的基本观念配合物(complexes)的基本观念配合物的异构(isomerism)现象一.配合物(complexes)的基本观念双齿配体 乙二胺(en) 联吡啶(bpy)大环配体配合物的模板(template)合成:Cu2+与2,
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Complexes：配合物
配合物基础和配位立体化学配合物(complexes)的基本观念配合物(complexes)的基本观念配合物的异构(isomerism)现象一.配合物(complexes)的基本观念双齿配体 乙二胺(en) 联吡啶(bpy)大环配体配合物的模板(template)合成:Cu2+与2,