Genetic dereplication of Trichoderma hypoxylon reveals two novel polycyclic lactones.

Previous study demonstrated large scale production of trichochecenes which limited the discovery of novel metabolites in Trichoderma hypoxylon. By genetic deletion of trichothecene synthase encoding gene thtri5, we created the dereplication mutant which eliminated the production of trichothecenes. Through chemical isolation, we characterized a couple of rare new polycyclic lactones tricholactones A and B from the thtri5 deletion strain. The structures of these two compounds were well determined by NMR, HR-ESI-MS and IECD analysis.