Three New Compounds from the Actinomycete Actinocorallia aurantiaca

Aurantiadioic acids A (1) and B (2), two new furan-containing polyketides, and aurantoic acid A (3), a new natural product, were isolated from the liquid fermentation of the sika deer dung-derived actinomycete Actinocorallia aurantiaca. The structures of the new compounds were established by extensive spectroscopic methods, including 1D & 2D NMR, HRESIMS spectroscopic analysis. The absolute configuration of 3 was assigned by comparison of the specific optical rotations with the reported derivatives. Biological activity evaluations suggested that compounds 1-3 showed weak inhibition on NO production in the murine monocytic RAW 264.7 macrophages with IC₅₀ values of 35.8, 41.8, 45.2 μM, respectively. Compound 3 showed weak inhibition on influenza A virus (A/PuertoRico/8/1934, H1N1) with an EC₅₀ value of 35.9 μM, and a selective index higher than 13.3.