Synthesis of enantiomerically pure divinyl- and diallylcarbinols
作者:Bernd Schmidt、Holger Wildemann
DOI:10.1039/b200976e
日期:2002.4.9
Acylated oxazolidinones and bornane sultams can be cleaved to divinyl- and diallylcarbinols by treatment with vinyl- or allylmetal compounds. For the preparation of divinylcarbinols, acylated bornane sultams are the starting materials of choice, while for the preparation of diallylcarbinols acylated oxazolidinones and bornane sultams work equally well.
Asymmetric alkylation of N-acylsultams: A general route to enantiomerically pure, crystalline C(α,α)-disubstituted carboxylic acid derivatives
作者:Wolfgang Oppolzer、Robert Moretti、Silvia Thomi
DOI:10.1016/s0040-4039(01)93810-9
日期:1989.1
Successive treatment of acylsultams with nBuLi or NHMDS and primary alkyl halides, followed by crystallization, gave pure C(α)-alkylation products and, via their non-destructive cleavage, enantiomerically pure alcohols or carboxylic acids .
efficient stereoselective synthesis of the C14–C29 fragment highlighting a coupling reaction between a 1,3-dithiane derivative and an α-branched aldehyde was realized. This highly convergent synthesis involved two chiral pools, L-malic acid and (+)-camphorsulfonic acid, which are the starting compounds to control the six stereogenic centers present in the C14–C29 fragment of amphidinol3.
The 15-membered cyclic depsipeptide boholamide A and an epimer were prepared by total synthesis for the first time, thus leading to a revision of C6 stereochemistry in the originally proposed structure of natural boholamide A. This convergent route features achievement of a macro-lactamization step in a gram scale. The revised boholamide A was sythesized with 16 linear steps in 5.46% overall yield
首次通过全合成制备了15元环状缩肽boholamide A和差向异构体,从而对最初提出的天然boholamide A结构中的C6立体化学进行了修正。该收敛路线的特点是实现了大环内酰胺化步骤以克为单位。修改后的 boholamide A 用 16 个线性步骤合成,总产率为 5.46%。这项工作促进了 boholamide A 作为潜在缺氧选择性抗癌剂的研究。