Synthesis of the C1−C28 Portion of Spongistatin 1 (Altohyrtin A)
作者:Michelle M. Claffey、Christopher J. Hayes、Clayton H. Heathcock
DOI:10.1021/jo9910987
日期:1999.10.1
A synthetic approach was developed to the C1-C28 subunit of spongistatin 1 (altohyrtin A, 65). The key step was the coupling of the AB and CDspiroketal moieties via an anti-aldol reaction of aldehyde 62 and ethyl ketone 57. The development of a method for the construction of the AB spiroketal fragment is described and included the desymmetrization of C(2)-symmetric diketone 10 and the differentiation
Highly Selective Hydrolytic Kinetic Resolution of Terminal Epoxides Catalyzed by Chiral (salen)Co<sup>III</sup> Complexes. Practical Synthesis of Enantioenriched Terminal Epoxides and 1,2-Diols
作者:Scott E. Schaus、Bridget D. Brandes、Jay F. Larrow、Makoto Tokunaga、Karl B. Hansen、Alexandra E. Gould、Michael E. Furrow、Eric N. Jacobsen
DOI:10.1021/ja016737l
日期:2002.2.1
The hydrolytickineticresolution (HKR) of terminal epoxides catalyzed by chiral (salen)Co(III) complex 1 x OAc affords both recovered unreacted epoxide and 1,2-diol product in highly enantioenriched form. As such, the HKR provides general access to useful, highly enantioenriched chiral building blocks that are otherwise difficult to access, from inexpensive racemic materials. The reaction has several
A methodology is described for the synthesis of 2,6-disubstituted dihydro[2H]pyrans through a Lewis-acidcatalyzed 6-endo-trig cyclization of β-hydroxy-γ,δ-unsaturated alcohols. Employing alkyl-substituted allylic diols and catalytic amounts of a Lewis acid, such as BF3·OEt2, the corresponding syn-pyrans are formed highly diastereoselectively and in good yields. The described process is simple to execute
Synthesis and Biophysical Studies on 35-Deoxy Amphotericin B Methyl Ester
作者:Alex M. Szpilman、Damiano M. Cereghetti、Jeffrey M. Manthorpe、Nicholas R. Wurtz、Erick M. Carreira
DOI:10.1002/chem.200900231
日期:2009.7.20
amphotericin B is presented. A modular strategy for the synthesis of amphotericin B and its designed analogues is developed, which relies on an efficient gram‐scale synthesis of various subunits of amphotericin B. A novel method for the coupling of the mycosamine to the aglycone was identified. The implementation of the approach has enabled the preparation of 35‐deoxy amphotericin Bmethylester. Investigation
Stereoselective Synthesis of Coreoside D and Determination of Its Absolute Configuration
作者:Narihito Ogawa、Ryoya Imaizumi
DOI:10.1055/s-0039-1690876
日期:2020.9
We report the stereoselectivesynthesis of (3S)- and (3R)-coreoside D. The conjugated diyne in the C1–C14 moiety was synthesized through two types of palladium-catalyzed cross-coupling reaction. The introduction of the glucopyranose was achieved by a glycosylation reaction using an imidate derivative in the presence of a Lewis acid. The asymmetric center at the C3-position was constructed by the chiral-pool
我们报告了 (3S)- 和 (3R)-coreoside D 的立体选择性合成。 C1-C14 部分中的共轭二炔是通过两种钯催化的交叉偶联反应合成的。在路易斯酸的存在下,通过使用亚胺酸酯衍生物的糖基化反应来实现吡喃葡萄糖的引入。C3 位的不对称中心是通过手性池方法使用 d-苹果酸构建的。通过比较合成立体异构体的 [α] D 值与天然产物报道的值,确定天然产物 C3 位的立体化学为 R。