nidulans strains expressing all the putative bue cluster genes (bueA/B/C/D/E/F/G/R) showed a peak matching 1 with m/z of 537 [M -H] -, which was not observed in the control strain (Fig. ). The UV-vis spectrum matched the profile for 1 previously observed in A. burnettii extracts (Fig. ). When comparing strains with and without the vector for TF overexpression, we observed a ~2-fold increase in compound production in the strains containing the vector encoding PgpdA-bueR and bueG (Fig. ). We decided to proceed with strains with TF overexpression to facilitate downstream compound isolation. We isolated 1 (1.1 g) from a large-scale solid-phase cultivation of A. nidulans (bueA/B/C/D/E/F/G/R) on jasmine rice. The NMR data for the isolated compound were identical to those for 1 isolated from A. burnettii (Figs. S9-10 †). This validates that the putative bue cluster is indeed responsible for the biosynthesis of 1.