Natural Brominated Fatty Acid-containing Flavonoids Bromaliphflas A-B From Marine-derived Streptomyces qinglanensis 1678.

Two new brominated fatty acid-containing flavonoids (1 and 2), together with the known compound 5-hydroxy-3',4',7-trimethoxyflavone (HTMF) (3), were obtained from marine-derived Streptomyces qinglanensis 1678. The structures of the new isolates were established on the basis of their electrospray ionization high-resolution mass spectrometry, one-, and two-dimensional nuclear magnetic resonance datasets. Bioactivity results show that compounds 2 and 3 exhibited moderate anti-inflammatory bioactivities. It seems that HTMF substitution could enhance the bioactivities of the anti-inflammatory bioactivities of 8-bromohexanoic acid, however, the influence of 6/8-bromohexanoic acid on the anti-inflammatory bioactivities of HTMF may depend on the length of the fatty chain.