Abstract Concise and efficient syntheses of d-lyxo-phytosphingosine and pachastrissamine were achieved utilizing a chiral oxazine. The key features in these strategies are the stereoselectiveintramolecular oxazine formation catalyzed by palladium(0), and intermolecular olefin cross-metathesis. Concise and efficient syntheses of d-lyxo-phytosphingosine and pachastrissamine were achieved utilizing a
摘要 d - lyxo -physphingosine和pachastrissamine的合成简单高效,是利用手性恶嗪实现的。这些策略的关键特征是钯(0)催化的立体选择性分子内恶嗪的形成,以及分子间烯烃的交叉复分解。 d - lyxo -physphingosine和pachastrissamine的合成简单高效,是利用手性恶嗪实现的。这些策略的关键特征是钯(0)催化的立体选择性分子内恶嗪的形成,以及分子间烯烃的交叉复分解。
A Stereocontrolled, Efficient Synthetic Route to Bioactive Sphingolipids: Synthesis of Phytosphingosine and Phytoceramides from Unsaturated Ester Precursors via Cyclic Sulfate Intermediates
作者:Linli He、Hoe-Sup Byun、Robert Bittman
DOI:10.1021/jo001225v
日期:2000.11.1
4-O-protected (E)-alpha,beta-unsaturated ester 5 (generated by dihydroxylation of 1-hexadecene, followed by oxidation to the aldehyde and Horner-Wadsworth-Emmons olefination), (ii) conversion to cyclicsulfate intermediate 7, and (iii) regioselective alpha-azidation of 7. Reduction of 4-O-protected 2-azido ester 8 via alpha-azidolactone 9 afforded phytosphingosine 1a. Staudinger reduction of the azido
Phytosphingosines — a facile synthesis and spectroscopic protocol for configurational assignment
作者:Osamu Shirota、Koji Nakanishi、Nina Berova
DOI:10.1016/s0040-4020(99)00839-x
日期:1999.11
based on a two-step derivatization to 2-N-naphthimide- 1,3,4-O-trinaphthoate derivatives which gives rise to unique excitoncoupledcirculardichroic and 1H-NMR spectra in selected solvents. The spectra can be used as reference data for assignment of relative as well as absolute configurations of phytosphingosine isomers and congeners at the low-nanomole level.
通过使用Wittig和Julia烯化反应,然后进行Sharpless二羟基化反应,已轻松合成了植物鞘氨醇的8种构型异构体中的4种。这四种立体异构体的集合用作模型化合物,用于开发用于分配所有植物鞘氨醇异构体的相对和绝对构型的通用化学/ CD / NMR方案。该程序基于两步衍生化为2- N-萘酰亚胺-1,3,4 - O-叔萘甲酸酯衍生物,这在选定的溶剂中产生了独特的激子耦合的圆二色性光谱和1 H-NMR光谱。光谱可用作参考数据,用于分配低鞘氨醇水平的植物鞘氨醇异构体和同类物的相对和绝对构型。
Regioselective Inversion of the Hydroxyl Group in <scp>d</scp>-<i>ribo</i>-Phytosphingosine via a Cyclic Sulfate and Bis-Sulfonate Intermediate
作者:Yun Mi Lee、Dong Jae Baek、Seokwoo Lee、Deukjoon Kim、Sanghee Kim
DOI:10.1021/jo101757k
日期:2011.1.21
The selective synthesis of d-xylo- and d-lyxo-phytosphingosines from commercially available d-ribo-phytosphingosine is described. Thermolysis of the N-carbonyl protectedcyclic sulfate led to an inversion of configuration of the proximal hydroxylgroup to give the xylo-isomer, whereas the corresponding bis-sulfonate resulted in an inversion of configuration of the distal hydroxylgroup to give the lyxo-isomer
[EN] EFFICIENT METHODS FOR Z- OR CIS-SELECTIVE CROSS-METATHESIS<br/>[FR] PROCÉDÉS EFFICACES DE MÉTATHÈSE CROISÉE Z-SÉLECTIVE OU CIS-SÉLECTIVE
申请人:TRUSTEES BOSTON COLLEGE
公开号:WO2011097642A1
公开(公告)日:2011-08-11
The present invention generally relates to methods for performing metathesis reactions, including cross-metathesis reactions. Methods described herein exhibit enhanced activity and stereoselectivity, relative to known methods, and are useful in the synthesis of a large assortment of biologically and therapeutically significant agents.