1. Barcelona Biomedical Research Institute and Combinatorial Chemistry Unity, Barcelona Science Park, University of Barcelona, Josep Samitier 1, 08028-Barcelona, Spain, Department of Organic Chemistry, University of Barcelona, Martí i Franqués 1, 08028-Barcelona, Spain, and PharmaMar, Avda Reyes Católicos 1, 28770-Colmenar Viejo, Madrid, Spain