structural and mechanistic studies on the organocatalytic asymmetrictransferhydrogenation of ketimines with trichlorosilane. Amines were obtained in good yields and moderate enantioselectivities. Both experiment and computation were utilized to provide an improved understanding of the mechanism. amines - Lewis bases - organocatalysis - transferhydrogenation - trichlorosilane
3. leads to amide products which can be hydrolyzed under mild conditions. The amidation reaction is mild, general and compatible with both primary C−H bonds of tertiary and secondary alcohols, as well as secondary C−H bonds of cyclic secondary alcohols. This method provides an easy access to free 1,2-aminoalcohols after efficient and mild cleavage of the oxime directing group and activated amide.
Evolution of the Total Syntheses of Ustiloxin Natural Products and Their Analogues
作者:Pixu Li、Cory D. Evans、Yongzhong Wu、Bin Cao、Ernest Hamel、Madeleine M. Joullié
DOI:10.1021/ja710363p
日期:2008.2.1
synthetically challenging chiral tertiary alkyl-aryl ether linkage. The first total synthesis of ustiloxin D was achieved in 31 linear steps using an S(N)Ar reaction. An NOE study of this synthetic product showed that ustiloxin D existed as a single atropisomer. Subsequently, highly concise and convergent syntheses of ustiloxins D and F were developed by utilizing a newly discovered ethynyl aziridine ring-opening
Ustiloxins AF 是抗有丝分裂杂环肽,含有 13 元环状核心结构,具有合成上具有挑战性的手性叔烷基芳基醚键。使用 S(N)Ar 反应,通过 31 个线性步骤实现了 ustiloxin D 的首次全合成。该合成产品的 NOE 研究表明乌司洛辛 D 作为单一阻转异构体存在。随后,利用新发现的乙炔基氮丙啶开环反应,以 15 个步骤的最长线性序列开发了乌斯蒂洛辛 D 和 F 的高度简洁和收敛的合成方法。该方法进一步优化以实现更好的大环内酰胺化策略。通过第二代制备了乌斯蒂洛辛D、F和8个类似物(14-MeO-乌斯蒂洛辛D、4个C-6位氨基酸残基不同的类似物、以及3个(9R,10S)-表乌斯蒂洛辛类似物)路线。对这些化合物作为微管蛋白聚合抑制剂的评估表明,C-6 位的变化在一定程度上是可以容忍的。相反,C-9 甲氨基的 S 构型和游离酚羟基对于抑制微管蛋白聚合至关重要。
[EN] HEPATITIS C VIRUS INHIBITORS<br/>[FR] INHIBITEURS DU VIRUS DE L'HÉPATITE C
申请人:BRISTOL MYERS SQUIBB CO
公开号:WO2011059850A1
公开(公告)日:2011-05-19
The present disclosure relates to methods for making compounds useful in the treatment of Hepatitis C virus (HCV) infection.