Two new alkaloids from a strain of endophytic fungus Aspergillus sp.

19-Hydroxybrevianamide M (1) and 6 R-methoxybrevianamide V (2), two new alkaloids, were isolated from an extract of the endophytic fungus Aspergillus sp. JNU18HC0517J, together with six known analogues (3- 8). Their structures were elucidated by extensive spectroscopic analyses, NMR calculations, and ECD calculations. 6 R-methoxybrevianamide V (2) was the first L-proline indole DKP alkaloid with substitution at C-6 on the proline ring. Furthermore, the cytotoxities and antimicrobial activities of these isolated compounds were also evaluated. Compound 8 exhibited moderate antibacterial activity against Staphylococcus aureus 209 P with a minimal inhibitory concentration (MIC) value of 16 mu g/ml. [GRAPHICS] .

Automated summary

Two new alkaloids, 19-Hydroxybrevianamide M (1) and 6 R-methoxybrevianamide V (2), were isolated from the extract of the endophytic fungus Aspergillus sp. JNU18HC0517J, along with six known analogues (3-8). Their structures were determined using extensive spectroscopic analyses, NMR calculations, and ECD calculations. 6 R-methoxybrevianamide V (2) is the first L-proline indole DKP alkaloid with substitution at C-6 on the proline ring. The cytotoxicities and antimicrobial activities of these compounds were also evaluated, with compound 8 showing moderate antibacterial activity against Staphylococcus aureus 209 P with a minimal inhibitory concentration (MIC) value of 16 μg/ml.