**4. Conclusions**

Ten metabolites, including three new dimeric naphtha-γ-pyrones, teratopyrones A–C (**1**–**3**), were isolated from a PDA culture of the endophytic fungus, *Teratosphaeria* sp. AK1128. This constitutes the second report of the occurrence of secondary metabolites in a fungus of the family Teratosphaeriaceae. The ECD spectra of teratopyrones A–C suggested that all three of them have negative exciton chirality. Cytotoxicity data for nigerasperone A (**7**) from this and previous studies suggest that it has selective activity for certain cancer cell lines.

**Supplementary Materials:** The following are available online, Figure S1: 1H NMR Spectrum (400 MHz) of Teratopyrone A (1) in CDCl3, Figure S2. 13C NMR Spectrum (100 MHz) of Teratopyrone A (1) in CDCl3, Figure S3. HSQC Spectra (400 MHz) of Teratopyrone A (1) in CDCl3, Figure S4. HMBC Spectra (400 MHz) of Teratopyrone A (1) in CDCl3, Figure S5. 1H NMR Spectrum (400 MHz) of Teratopyrone B (2) in DMSO-d6, Figure S6. 13C NMR Spectrum (100 MHz) of Teratopyrone B (2) in DMSO-d6, Figure S7. HSQC Spectrum (400 MHz) of Teratopyrone B (2) in DMSO-d6, Figure S8. HMBC Spectrum (400 MHz) of Teratopyrone B (2) in DMSO-d6, Figure S9. 1H NMR Spectrum (400 MHz) of Teratopyrone C (3) in DMSO-d6, Figure S10. 13C NMR Spectrum (100 MHz) of Teratopyrone C (3) in DMSO-d6, Figure S11. HSQC Spectrum (400 MHz) of Teratopyrone C (3) in DMSO-d6, Figure S12. HMBC Spectrum (400 MHz) of Teratopyrone C (3) in DMSO-d6, Figure S13. Results of maximum likelihood analysis placing strain AK1128 within *Teratosphaeria* with high support.

**Author Contributions:** Conceptualization, A.A.L.G. and A.E.A.; methodology, Y.-M.X., A.E.A., and J.M.U.; investigation, Y.-M.X., A.E.A., and J.M.U.; writing—original draft preparation, Y.-M.X.; writing—review and editing, A.A.L.G. and A.E.A.; supervision, A.A.L.G. and A.E.A.; funding acquisition, A.A.L.G. and A.E.A.; resources, A.A.L.G., A.E.A, L.-J.X. and W.-Q.W. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by National Institutes of Health, grant numbers R01 CA090625 and P41 GM094060.

**Acknowledgments:** We thank Patricia Espinosa-Artiles for fungal cultivation and Manping Liu for her help with the cytotoxicity assays.

**Conflicts of Interest:** A.A.L.G. has disclosed financial interests in Sun Pharma Advanced Research Co. Ltd., India and Regulonix, LLC. USA that are unrelated to the subject of the research presented here. All other authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
