Cover Picture: A Short Synthesis of Clionamine D (Chin. J. Chem. 11/2015)

The cover picture shows a short and efficient synthesis of clionamine D. Steroidal α ‐methylene‐ γ ‐lactones are versatile intermediates for synthesizing related natural products such as clionamines A–D, a family of marine natural alkaloids with potent autophagy bioactivities and unprecedented chemical structures. Employing single oxygen to break the C22‐C23 double bond via a [2+2]/retro‐[2+2] process, Shi and Tian et al . have developed a scalable, four‐step procedure to prepare α ‐methylene‐ γ ‐lactone directly from steroidal sapogenin–needn't prepare dinorcholanic lactone first. A synthesis of clionamine D was therefore achieved in eight steps with an overall yield of 31%. More details are discussed in the article by Tian et al . on page 1235–1238.