Stein, AnnikaCompera, DaveKarge, BiankaBrönstrup, MarkFranke, Jakob2019-09-132019-09-132019-01-01Beilstein J Org Chem. 2019 Aug 23;15:2003-2012. doi: 10.3762/bjoc.15.196. eCollection 2019.1860-53973150166710.3762/bjoc.15.196http://hdl.handle.net/10033/621934Withanolides are steroidal lactones widespread in Nightshade plants with often potent antiproliferative activities. Additionally, the structural diversity of this compound class holds much potential for the discovery of novel biological activity. Here, we report two newly characterised withanolides, named irinans, from Physalis peruviana with highly unusual truncated backbones that resemble mammalian androstane sex hormones. Based on biomimetic chemical reactions, we propose a model that links these compounds to withanolide biosynthesis. Irinans have potent antiproliferative activities, that are however lower than those of 4ß-hydroxywithanolide E. Our work establishes androwithanolides as a new subclass of withanolides.enAttribution-NonCommercial-ShareAlike 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-sa/4.0/Physalis peruvianaandrostanessteroidsstructure elucidationwithanolidesArticleBeilstein Journal of organic Chemistry