Novel Drimane Sesquiterpene Esters from Aspergillus ustus var. pseudodeflectus with Endothelin Receptor Binding Activity.

Terretonin, ophiobolin, and drimaneterpenes with absolute configurations from an algicolous Aspergillus ustus

“…The total EtOAc-soluble fraction (35.5 g) was subjected to stepgradient silica gel column chromatography (CC) with a solvent system consisting of 0-100% petroleum ether (PE)-EtOAc to afford 14 fractions (Frs. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] on the basis of TLC analysis. Fr.…”

“…In our ongoing program to discover new bioactive compounds from marine algae and their associated fungi, a fungus A. ustus isolated from the marine green alga Codium fragile was investigated. As a result, one new meroterpene, 1,2-dihydroterretonin F (2), five new sesterterpenes, (6a)-21-deoxyophiobolin G (3), (6a)-16,17-dihydro-21-deoxyophiobolin G (4), ophiobolin U (5), ophiobolin V (6), and ophiobolin W (7), two new sesquiterpenes, (6-strobilactone-B) esters of (E,E)-6,7-epoxy-2,4-octadienoic acids (13 and 14), and twelve known terpenes, terretonin F (1, revised), 6 (6a)-21,21-O-dihydroophiobolin G (8), 3 (5a,6a)-ophiobolin H (9), 3 ophiobolin H (10), 8 ophiobolin F (11), 9 3b,9a,11-trihydroxy-6-oxodrim-7-ene (12), 4 (6-strobilactone-B) esters of (E,E)-6,7-dihydroxy-2,4-octadienoic acids (15 and 16), 4 (6-strobilactone-B) ester of (E,E)-6-oxo-2,4-hexadienoic acid (17, Ustusolate E), 4,5 Ustusolate D (18), 5 9a-hydroxy-6b-[(2E,4E,6E)-octa-2,4,6-trienoyloxy]-5a-drim-7-en-11,12-olide (19), 10 and (29E,49E,69E)-6-(19-carboxyocta-29,49,69-triene)-11,12-epoxy-9,11-dihydroxydrim-7-ene (20), 10 were isolated and identified ( Fig. 1).…”

“…2) further confirmed the structures of 13 and 14 to be (6-Strobilactone-B) esters of (E,E)-6,7-epoxy-2,4-octadienoic acids. The remaining known compounds, including (6a)-21,21-O-dihydroophiobolin G (8), 3 (5a,6a)-ophiobolin H (9), 3 ophiobolin H (10), 8 ophiobolin F (11), 9 3b,9a,11-trihydroxy-6-oxodrim-7-ene (12), 4 (6-strobilactone-B) esters of (E,E)-6,7-dihydroxy-2,4-octadienoic acids (15 and 16), 4 (6-strobilactone-B) ester of (E,E)-6-oxo-2,4-hexadienoic acid (17, Ustusolate 10 and (29E,49E,69E)-6-(19-carboxyocta-29,49,69-triene)-11,12-epoxy-9,11-dihydroxydrim-7-ene (20), 10 were identified by detailed NMR data comparison with literature values.…”

Synthesis of FF8181-A

“…pseudodeflectus. 5) This compound inhibited the binding of endothelins to its receptors, so could be a lead compound to develop medicines for the circulatory system. FF8181-A (1) has recently been re-isolated as a promoter of proteasome-independent degradation of -catenin, along with FF8181-B (2) 5) and RES-1149-2 (3).…”

“…5) This compound inhibited the binding of endothelins to its receptors, so could be a lead compound to develop medicines for the circulatory system. FF8181-A (1) has recently been re-isolated as a promoter of proteasome-independent degradation of -catenin, along with FF8181-B (2) 5) and RES-1149-2 (3). [6][7][8] These compounds are understood to degrade -catenin, but the detailed degradation mechanism is still unclear (Yoshida, M., personal communication).…”