Synthesis of chinensines A-E.

Short and efficient syntheses of coronarin E (4) and chinensines A-E (5-9) have been accomplished. The use of two different types of reaction of singlet oxygen ((1)O(2)) lies at the heart of the synthetic strategy. The syntheses have facilitated the clarification of certain previously unknown, or unconfirmed, stereochemical details (the relativity stereochemistries of chinensines D and E and the absolute stereochemistries for all the synthesized family members).