Studies On The Total Syntheses Of 1, 3-dihydroxybenzene Macrolides Compounds: Asymmetric Total Syntheses Of Xestodecalactones B, C And 11-α-methoxycurvularin, 11-β-methoxycurvularin

This dissertation is mainly focused on the studies of the asymmetric total syntheses of 1,3-dihydroxybenzene macrolides xestodecalactones B and C and the studies of the asymmetric total syntheses of similarly natural products 11-α-methoxycurvularin and 11-β-methoxycurvulafin.It consisted of the following three parts:Chapter 1.The progress on the study of the macrolactonization reactions(review) The review is organized into two main parts to describe all macrolactonization reactions.The first of these two parts covers activation of the acid while the second covers,in a similarly broad sense,activation of the alcohol.Chapter 2.The First Asymmetric Total Syntheses and Determination of Absolute Configuations of Xestodecalactones B and CThe works of our group as well as other groups in the syntheses of 1,3-dihydroxybenzene macrolides natural products were described briefly.The first efficient asymmetric total syntheses of xestodecalactones B and C have been accomplished in 10 steps with an overall yield of 22%and 20.2%respectively.The key steps involve the utility of Evans oxazolidinone-mediated syn-aldol condensations to establish the C-9 configuration and the macrolides ring formation by intramolecular acylation.The absolute configuration of xestodecalactones B and C have been determined via these syntheses.Chapter 3.First Total Syntheses and Spectral Data Corrections of 11-α-Methoxycurvularin and 11-β-MethoxycurvularinThe introduction of three-component linchpin coupling reaction and the works of our group in this field were described briefly.The physiological activities of 1,3-dihydroxybenzene macrolides natural products were described briefly.Concise and efficient total syntheses of 11-α-methoxycurvularin and 11-β-methoxycurvularin were accomplished for the first time.The three-component linchpin coupling and intramolecular acylation reactions were key steps,in which we found the spectral data of 11-α-methoxycurvularin and 11-β-methoxycurvularin,reported in the literature,were reversed with each other.