Napyradiomycin A1 is a fungal metabolite originally isolated from C. rubra and has diverse biological activities.1,2 It is active against S. aureus, M. luteus, B. anthracis, C. bovis, and M. smegmatis (MICs = 1.56-12.5 µg/ml).1 Napyradiomycin A1 is an estrogen receptor antagonist (IC50 = 4.2 µM in rat uterine homogenates).2 It also inhibits mitochondrial NADH:ubiquinone oxidoreductase (complex I) and succinate:ubiquinone oxidoreductase (complex II) activities in bovine heart homogenates (IC50s = 20 and 9.7 µM, respectively).3
1.Shiomi, K., Iinuma, H., Hamada, M., et al.Novel antibiotics napyradiomycins. Production, isolation, physico-chemical properties and biological activityJ. Antibiot. (Tokyo)39(4)487-493(1986) 2.Hori, Y., Abe, Y., Shigematsu, N., et al.Napyradiomycins A and B1: Non-steroidal estrogen-receptor antagonists produced by a StreptomycesJ. Antibiot. (Tokyo)46(12)1890-1893(1993) 3.Yamamoto, K., Tashiro, E., Motohashi, K., et al.Napyradiomycin A1, an inhibitor of mitochondrial complexes I and IIJ. Antibiot. (Tokyo)65(4)211-214(2012)