of N-methyl amino acids and hydroxycarboxylic acids. We report herein an efficient synthesis of the anthelminticPF1022A and its commercial analogue emodepside on Kaiser and Wang resins. Our protocol provides the basis for the solid-phase synthesis of cyclodepsipeptide libraries with a high probability of anthelmintic, antibacterial or insecticidal activity.
环缩肽、PF1022 和 verticilide 家族代表了多种多样的非常有趣的天然产物,因为它们具有多种生物活性。然而,到目前为止,还没有完成这些化合物的切实可行的固相合成,这可能是由于 N-甲基氨基酸和羟基羧酸的组合存在问题。我们在此报告了一种在 Kaiser 和 Wang 树脂上有效合成驱虫剂 PF1022A 及其商业模拟物艾莫德苷的方法。我们的协议为环缩肽库的固相合成提供了基础,具有很高的驱虫、抗菌或杀虫活性。
Klebsiellapneumoniae (NBRC 3319) Mediated Asymmetric Reduction of α-Substituted β-Oxo Esters and Its Application to the Enantioiselective Synthesis of Small-Ring Carbocycle Derivatives
作者:Rajib Bhuniya、Tridib Mahapatra、Samik Nanda
DOI:10.1002/ejoc.201101695
日期:2012.3
Ketoreductases from Klebsiella pneumoniae (NBRC3319) selectively reduce several 2-substituted ethyl 3-oxobutyrates to yield the corresponding syn-β-hydroxy esters with remarkable stereocontrol (de > 99 %, ee > 99 %). The enantiopure hydroxy oxo esters were synthetically manipulated to access new small-ringcarbocycles.
Stereoselective Synthesis of Enantiopure Oxetanes, a Carbohydrate Mimic, an ϵ-Lactone, and Cyclitols from Biocatalytically Derived β-Hydroxy Esters as Chiral Precursors
Biocatalyticallyderivedenantiopure α-substituted β-hydroxyesters serve as excellent chirons for the synthesis of a diverse set of structures such as oxetanes, a carbohydratemimic, an ϵ-lactone, and carbocyclic and aromatic cyclitols. The starting materials can be easily accessed in enantiopure form from α-substituted β-keto esters by biocatalytic reduction with Klebsiella pneumoniae (NBRC 3319)