Stereochemical aspects of the biological oxidation of aryl isoprenoids. The asymmetric synthesis and absolute configuration of meranzin and of meranzin hydrate

The role of epoxides in the biological oxidation of aryl prenyl derivatives is discussed in terms of the stereochemistry of quinoline alkaloids and coumarins found in species of the Rutaceae and Umbelliferae. Asymmetric synthesis of the epoxide, meranzin and of the diol, meranzin hydrate, have been carried out and the absolute configurations of the two coumarins have been established.