Diastereodivergent and Regiodivergent Total Synthesis of Princepin and Isoprincepin in Both (7″R,8″R) and (7″S,8″S) Isomers.

The first total synthesis of (7″R,8″R)-, (7″S,8″S)-isomers of princepin (1) and (7″R,8″R)-, (7″S,8″S)-isomers of isoprincepin (2) was accomplished in a highly stereoselective manner via para quinomethide-mediated construction of the furofuran and 1,4-benzodioxane rings. Structural confirmation methods of 1 and 2 were established by CD and HPLC analysis of each diastereomers with natural products.