受到构象刚性的,同手性和杂手性的季铵溴化物1之间催化活性和立体控制能力的巨大差异的启发,设计并合成了构象柔性的4型N螺环手性季铵盐。通过重复使用邻位放大-卤化作为关键的合成工具,已经建立了制备适当取代的联苯亚基的可靠方法。在甘氨酸席夫碱2的不对称烷基化中评估了非手性联苯部分的结构与4的反应性和选择性之间的关系。在典型的相转移条件下,导致4l被鉴定为最佳催化剂结构,在与各种烷基卤化物的反应中表现出出色的对映体控制能力。通过X射线晶体学分析确定4l的分子结构,并通过变温1 H NMR研究检查其在溶液中的独特行为。这些研究揭示,所观察到的高的手性效率源于homochiral-的有效不对称相转移催化4升,迅速与heterochiral-平衡4升低的催化活性和立体选择性的。
受到构象刚性的,同手性和杂手性的季铵溴化物1之间催化活性和立体控制能力的巨大差异的启发,设计并合成了构象柔性的4型N螺环手性季铵盐。通过重复使用邻位放大-卤化作为关键的合成工具,已经建立了制备适当取代的联苯亚基的可靠方法。在甘氨酸席夫碱2的不对称烷基化中评估了非手性联苯部分的结构与4的反应性和选择性之间的关系。在典型的相转移条件下,导致4l被鉴定为最佳催化剂结构,在与各种烷基卤化物的反应中表现出出色的对映体控制能力。通过X射线晶体学分析确定4l的分子结构,并通过变温1 H NMR研究检查其在溶液中的独特行为。这些研究揭示,所观察到的高的手性效率源于homochiral-的有效不对称相转移催化4升,迅速与heterochiral-平衡4升低的催化活性和立体选择性的。
Base-Induced Mechanistic Variation in Palladium-Catalyzed Carbonylation of Aryl Iodides
作者:Yanhe Hu、Jing Liu、Zhixin Lü、Xiancai Luo、Heng Zhang、Yu Lan、Aiwen Lei
DOI:10.1021/ja909962f
日期:2010.3.10
facile alkoxycarbonylation and thiocarbonylation. The ethoxycarbonylation of aryl iodides under room temperature and balloon pressure of CO in the presence of EtONa were examined, and good to high yields were obtained; the t-butoxycarbonylation reactions in the presence of t-BuONa were achieved, and the alkylthiocarbonylation (including the t-butylthiocarbonylation) of aryl iodides in the presence of sodium
direct cross‐coupling reaction between diarylzinc (Ar2Zn) and aryltrimethylammonium salts (ArNMe3+⋅−OTf) in the presence of LiCl, via C−N bond cleavage. The reaction takes place smoothly upon heating in THF without any external catalyst, enabling an efficient and chemoselective formation of biaryl products. Mechanistic studies indicate that the reaction proceeds through a single electrontransfer route
ANTHRACYCLINE DISULFIDE INTERMEDIATES, ANTIBODY-DRUG CONJUGATES AND METHODS
申请人:GENENTECH, INC.
公开号:US20160074528A1
公开(公告)日:2016-03-17
The invention provides antibody-drug conjugates comprising an antibody conjugated to an anthracycline drug moiety via a disulfide linker, anthracycline disulfide intermediates, and methods of using the antibody-drug conjugates.
The present invention relates to compounds of the formula
which are useful in treating diseases characterized by the hyperactivity of MEK. Accordingly the compounds are useful in the treatment of diseases, such as, cancer, cognative and CNS disorders and inflammatory/autoimmune diseases.
A revisit of organoaluminumreagents for cross-coupling reactions has opened up several types of C–C bond formation protocols through cleavage of phenolic/alcoholic C–O and C–F and ammonium C–N bonds. Catalyzed by the commercially available NiCl2(PCy3)2 catalyst, these reactions proceed smoothly with a wide range of substrates and broad functional group compatibility, providing a versatile methodology