Diketopiperazines produced by endophytic fungi found in association with two Asteraceae species - Guimarães, Denise O.; Borges, Warley S.; Vieira, Noemi J.; Oliveira, Laiani F. de; Silva, Carlos Henrique Tomich de Paula da; Lopes, Norberto Peporine; Dias, Luís Gustavo; Durán-Patrón, Rosa; Collado, Isidro G.; Pupo, Mônica Tallarico (Phytochemistry, 2010)