New Angucyclinones from the Marine Mollusk Associated Actinomycete Saccharothrix espanaensis An 113

Abstract

Three new angucyclinones, saccharothrixins A (6), B (7) and C (8), together with five known analogues, X-14881 A (1), X-14881 E (2), ochromycinone (3), X-14881 C (4) and X-14881 B (5), were isolated from the actinomycete Saccharothrix espanaensis An 113 associated with the marine mollusk Anadara broughtoni. The structures of the new compounds were elucidated by spectroscopic methods including one-and two-dimensional NMR and by comparison of the NMR data with those of the structurally related known angucyclinone X-14881 A (1).

New Angucyclines and Antimicrobial Diketopiperazines from the Marine Mollusk-Derived Actinomycete Saccharothrix espanaensis An 113

“…Further purification of the most polar fraction of the ethyl acetate extract of the culture broth by silica gel column chromatography and reversedphase HPLC afforded the compounds 2-6. The ultraviolet absorption spectrum of 3 in methanol exhibited maxima at 248 and 282 nm, which is nearly identical with that of 1 [4], indicating the presence of the same chromophore. The molecular formula of 3 is C 26 H 34 O 9 based on the HRESI-MS: m/z 513.2086 [M+Na] + ; 525.1890 [M+Cl] -; 489.2145 [M-H] -.…”

“…Instruments used for the measurements of melting points, optical rotations, IR, UV, NMR, EIMS and HRESIMS have been reported in an earlier publication [4]. HPLC analysis was conducted with an Agilent 1100 Series instrument (USA) on a Discovery C18 column (10 x 250 mm, 5 μm, Supelco).…”

“…In a previous paper [4], three new angucyclinones, saccharothrixins A, B and C together with five known analogues were found in the culture broth of the actinomycete Saccharothrix espanaensis An 113 associated with the marine mollusk Anadara broughtoni. Further purification of the most polar fraction of the ethyl acetate extract of the culture broth by silica gel column chromatography and reversedphase HPLC afforded the compounds 2-6.…”

“…A difference of 146 mass units compared to 1 suggested that 1 was the aglycone of 3. The long-range coupling between H-1' and C-7 in the [4,5] ( Figure 1).…”

Natural Products of Actinobacteria Derived from Marine Organisms

“…Angucyclines are usually retained or derived from a benz[a]anthracene moiety. Saccharothrix espanaensis isolated from the mollusc Anadara broughtoni (Peter the Great Bay, Sea of Japan, Russia) produced angucyclines, saccharothrixins A-C (6-8), which exhibited modest antibacterial activity [72]. Saccharothrix espanaensis isolated from the mollusc Anadara broughtoni (Peter the Great Bay, Sea of Japan, Russia) produced angucyclines, saccharothrixins A-C (6-8), which exhibited modest antibacterial activity [72].…”