Back Cover
Abstract
The back cover picture shows a protecting-group-free palladium-catalyzed allylic coupling of cucurbitacin B, a natural product mainly found in cucurbitaceous plants. This convenient method provided a one-step approach to expand the chemical diversity of the C25 site of cucurbitacin B. Some of the compounds showed higher cytotoxicity against A549 cells than cucurbitacin B. More details are discussed in the article by Nan et al. on page 1662–1666.