A bacterial metabolite with diverse biological activities; inhibits TNF-α-induced NF-κB transcriptional activity and decreases proliferation of HUVECs at 5-20 μM; decreases viability of, as well as induces apoptosis and increases the production of ROS in Hep3B cells at 12 μg/ml; does not induce cytotoxicity in RBL-2H3 mast cells at concentrations up to 100 μM; prevents degranulation in antigen-stimulated mast cells, and inhibits Syk, LYN, and Fyn kinases, and reduces DNP-HSA-induced TNF-α and IL-4 secretion in RBL-2H3 mast cells; decreases swelling and reduces scratching behavior in a mouse model of DNFB-induced allergic dermatitis