Bioactive Streptoglutarimides A-J from the Marine-Derived sp. ZZ741.

The new streptoglutarimides A-J (-) and the known streptovitacin A () were isolated from a marine-derived actinomycete, sp. ZZ741. Structures of the isolated compounds were elucidated based on their HRESIMS data, extensive NMR spectroscopic analyses, ECD calculations, Mosher's method, and a single-crystal X-ray diffraction experiment. Streptoglutarimide H () and streptovitacin A () showed potent antiproliferative activity against human glioma U87MG and U251 cells with IC values of 1.5-3.8 μM for and 0.05-0.22 μM for . All isolated compounds exhibited antimicrobial activity with MIC values of 9-11 μg/mL against methicillin-resistant , 8-12 μg/mL against , and 8-20 μg/mL against .