Abstract
The thesis concerns with the nitroso-Diels Alder (NDA) reactions of masked o-benzoquinones (MOBs) and application of this methodology to synthesize many kinds of conduramines. The thesis contain two major aspects : the first part concerned with the asymmetric nitroso-Diels-Alder (ANDA) reactions of MOBs and solving the hydrolyzing problem of NDA adducts. The second part applies the methodologies developed in the first part to furnish the syntheses of ent-conduramine A-1 tetraacetate, (+)-conduramine A-1, (+)-conduramine E-1 and (+)-ent-conduramine F-1. In the first chapter, we found ANDA reactions of MOBs with (+)-ketopinohydroxamic acid derived from (+)-camphorsulfonic acidshows the high yield and disastereoselectivities, the value of diastereomeric excess is up to 99 %. Interestingly, the major product is decided by the substituent on the MOB. With the evidences of ORTEP diagrams, we got the relationship between specific rotation and absolute configuration of these compounds. Furthermore, we solve the hydrolyzing problem of NDA adducts till we change the amino group to azide group, and we got a new rearrangement product.Utilizing the methodology of ANDA reactions of catechol has one MOM protection with (+)-ketopinohydroxamic and (-)-ketopinohydroxamic acid to furnish the syntheses of ent-conduramine A-1 tetraacetate and (+)-conduramine A-1, these are obtained from ten steps and eight steps separately. After getting the ANDA adduct from guaiacol and (+)-ketopinohydroxamic acid, we applied the methodology of new rearrangement developed in the first chapter to synthesize (+)-conduramine E-1 and (+)-ent-conduramine F-1 with ten steps and eight steps separately.