The Revised Structure, Total Synthesis, and Absolute Configuration of Streptophenazine A

A total synthesis of both diastereomers of the originally proposed structure for streptophenazine A (1) has been achieved. However, both synthetic compounds are different from the natural product. Re-examination of NMR data reported for streptophenazine A and a concise total synthesis of both diastereomers of 17 (17a and 17b) led to the structural revision of streptophenazine A to 17b. Asymmetric synthesis of (-)streptophenazine A was also conducted, and its absolute configuration was determined to be 1' S,2' R.