Catalytic Enantioselective Silylation of Acyclic and Cyclic Triols: Application to Total Syntheses of Cleroindicins D, F, and C
作者:Zhen You、Amir H. Hoveyda、Marc L. Snapper
DOI:10.1002/anie.200805338
日期:2009.1.5
Pick one out of three: Acyclic and cyclic 1,2,3‐triols are silylated with exceptional site‐ and enantioselectivity by a small‐molecule catalyst to afford silyl ethers having a neighboring diol moiety. The new process is applied to the enantioselectivetotalsyntheses of three cleroindicins, natural products isolated from a plant used in China to battle malaria and rheumatism.
Disclosed is a noble &bgr;-hydroxyamide of general formula wherein R
1
is alkyl, alkoxyalkyl or hydroxyalkoxyalkyl derived from at least one hydroxyfunctional compound, R
2
is alkyl, aryl, alkylaryl or arylalkyl derived from at least one carboxyfunctional compound or at least one anhydride, halide or ester of at least one carboxyfunctional compound, R
3
is N-alkyl or N-cycloalkyl derived from at least one alkanolamine and wherein m and n are independent integers and at least 1. In a further aspect the present refers to a process for synthesis of said &bgr;-hydroxyamide. The process comprises the Steps of (i) subjecting a di, tri or polyalcohol to alcoholysis with at least one di, tri or polyalkyl ester of a di, tri or polyfunctional carboxylic acid and (ii) subjecting obtained reaction product to aminolysis with at least one alkanolamine.
1
Symmetrical polyols, polyol esters, polyesters, polyurethanes, triazoles, and polyvinylethers derived from glycerol and methods of making the symmetrical polyols, polyesters, polyurethanes, polyhydroxyvinylethers and triazoles are discussed. Also provided is a method of making serinol.
The transition-metal-catalysed cross-couplingreaction has established itself as one of the most reliable and practical synthetic tools for the efficient construction of carbon–carbon/heteroatom (p-block elements other than carbon) bonds in both racemic and enantioselective manners. In contrast, development of the corresponding heteroatom–heteroatom cross-couplings has so far remained elusive, probably
过渡金属催化的交叉偶联反应已成为高效构建碳-碳/杂原子的最可靠和实用的合成工具之一(p-除碳以外的嵌段元素)以外消旋和对映选择性方式键合。相比之下,迄今为止,相应的杂原子-杂原子交叉偶联的发展仍然难以捉摸,这可能是由于研究不足且通常具有挑战性的杂原子-杂原子还原消除。在这里,我们基于实验和理论结果展示了使用单电子还原消除作为在 Cu 催化下开发对映选择性 S-O 偶联的策略。该反应通过制备具有拥挤立体中心的具有挑战性的手性醇、生物质衍生的原料甘油的权宜之计以及肌醇的显着催化 4,6-去对称化,显示了其合成潜力。
Arzneimittel mit verbesserter Penetration der Gewebsmembran
申请人:Max-Planck-Gesellschaft zur Förderung
der Wissenschaften e.V.
公开号:EP0144069A1
公开(公告)日:1985-06-12
Ein Arzneimittel mit verbesserter Penetration der Gewebsmembran des Zielorgans besteht aus einem Wirkstoff in Kombination mit einer Verbindung der allgemeinen Formel
in der einer der Reste R, und R2 eine Alkyl-, Alkylen-, Alkinyl-oder Alkoylgruppe mit je 3 bis 7 C-Atomen und der andere Rest ein H-Atom bedeutet und üblichen pharmazeutischen Zusatz- und Verdünnungsmitteln.
一种能更好地穿透目标器官组织膜的药物由活性成分与通式化合物(其中一个基团 R 和 R2 是烷基、亚烷基、炔基或烷酰基,每个基团有 3 至 7 个碳原子,另一个基团是 H 原子)以及常规药物添加剂和稀释剂组合而成。