The first total synthesis of lyngbyabellin A, a novel peptolide from the marine cyanobacterium Lyngbyamajuscula, is described. Both functionalized thiazole carboxylic acid units were synthesized using our CMD (chemical manganese dioxide) oxidation from the corresponding thiazolidines. The asymmetric synthesis of the dichlorinated β-hydroxy acid was achieved by the chiral oxazaborolidinone mediated
Isolation, Structure Determination, and Biological Activity of Lyngbyabellin A from the Marine Cyanobacterium <i>Lyngbya </i><i>m</i><i>ajuscula</i>
作者:Hendrik Luesch、Wesley Y. Yoshida、Richard E. Moore、Valerie J. Paul、Susan L. Mooberry
DOI:10.1021/np990543q
日期:2000.5.1
a significantly cytotoxic compound with unusual structural features, was isolated from a Guamanian strain of the marine cyanobacterium Lyngbya majuscula. This novel peptolide is structurally related to dolabellin (2) in that both depsipeptides bear a dichlorinated beta-hydroxy acid and two functionalized thiazole carboxylic acid units. Its gross structure has been elucidated by spectral analysis,
In this study, we document the firsttotalsynthesis of the marine cyanobacteria secondary metabolite 27-deoxylyngbyabellin A in 10 linear steps with 9.7% overall yield. Key steps entailed (1) one-pot cascade reaction of (S)-2-(benzyloxy)-3-methylbutanoic acid and of Boc-l-Ile-OH with a β-azido disulfide building block to access two critical thiazole units, (2) chiral oxazaborolidinone-mediated asymmetric
在这项研究中,我们记录了海洋蓝细菌次级代谢产物27-deoxylyngbyabellin A的第一个全合成,该合成以10个线性步骤进行,总收率为9.7%。关键步骤包括(1)(S)-2-(苄氧基)-3-甲基丁酸和Boc-1-Ile-OH与β-叠氮基二硫键的一锅级联反应,以访问两个关键的噻唑单元, (2)手性草氮杂硼硼烷酮介导的不对称醛醇缩合反应以构建(S)-β-羟基酯,以及(3)二苯叠氮磷酸酯介导组装的线性前体的大内酰胺化,从而获得天然产物27-脱氧lyngbyabellin A.
Total syntheses of lyngbyabellins A and B, potent cytotoxic lipopeptides from the marine cyanobacterium Lyngbya majuscula
The first total syntheses of lyngbyabellins A and B, Lyngbya majuscula derived lipopeptides, are described. The functionalized thiazole carboxylic acid units were prepared by the oxidative dehydrogenation of the corresponding thiazolidines with chemical manganese dioxide. The asymmetric synthesis of the dichlorinated β-hydroxy acid by a chiral oxazaborolidinone mediated aldol reaction. Finally, fragment