Discovery of a Dimeric Zinc Complex and Five Cyclopentenone Derivatives from the Sponge-Associated Fungus Aspergillus ochraceopetaliformis
ACS Omega. 2021 Mar 26;6(13):8942-8949. doi: 10.1021/acsomega.0c06218. eCollection 2021 Apr 6.
In devotion to investigating structurally novel and biologically active marine natural products, a dimer of a zinc complex, dizinchydroxyneoaspergillin (1), aspernones A-E (2–6), five cyclopentenone derivatives together with known polyketides (7–10), and neoaspergillic acid analogues (11–14) were isolated from the sponge-associated fungus Aspergillus ochraceopetaliformis SCSIO 41018. Their structures were elucidated on the basis of spectroscopic analysis, electronic circular dichroism (ECD) analysis, and X-ray diffraction. Dizinchydroxyneoaspergillin (1) displayed significant bactericide effects toward methicillin-resistant Staphyloccocus aureus, Staphyloccocus aureus, Enterococcus faecalis, Acinetobacter baumannii, and Klebsiella pneumonia with MIC values of 0.45-7.8 μg/mL and moderate in vitro cytotoxic activities against the K562, BEL-7402, and SGC-7901 cell lines with IC50 values of 12.88 ± 0.14, 15.83 ± 0.23, and 15.08 ± 0.62 μM, respectively. This is the first time to report the dimer of the zinc complex of hydroxyneoaspergillic acid conjunction at Zn-N-4 by a coordination bond. Additionally, compound 1 displayed significant antibacterial and cytotoxic activities, which would be a promising drug lead and could attract much attention from both chemists and pharmacists.