α-Glucosidase and lipoxygenase inhibitory derivatives of cryptosporioptide from the endophytic fungusCryptosporiopsissp.

Abstract

Two new cryptosporioptide-derived polyketides cryptosporioptides A (2) and B (3) were isolated from the extract of endophytic fungus Cryptosporiopsis sp. associated with the shrub, Viburnum tinus. The structures of the isolates were determined through spectral analysis including 1D NMR ((1)H, (13)C) and 2D NMR (HSQC, HMBC, COSY) techniques, HR-FAB-MS and by comparison with the reported data of cryptosporioptide (1). The relative stereochemistry was assigned with the help of NOESY analysis, the molecular model, and comparison of the optical rotation values with the reference compound 1.

Secondary metabolites from hypocrealean entomopathogenic fungi: novel bioactive compounds

“…84 Related cryptosporioptides with a malonate bridge, and those with only the xanthone-derived core and their dimers, were previously isolated from Cryptosporiopsis sp. 8999, 85,86 and their biosynthesis has recently been elucidated. 87 Compound 22 displays in vitro inhibitory activity against the protein tyrosine phosphatases PTP1B, SHP2, CDC25B and SHP1 in the 5 to 8 μM range.…”

Bioactive Polyhydroxanthones from Penicillium purpurogenum

“…The dimers 5 – 8 are closely related to cryptosporioptides, which, originally characterized as ring-contracted xanthone monomers, − were recently reassigned to xanthone dimers having the same planar tetrahydroxanthone core unit as the former, in particular cryptosporioptide D, which has the same 5/5′- O -acyl subunit as 6 . They differ from cryptosporioptides in that the 6,7/6′,7′-epoxy group is oriented in the same direction as the 10a/10a′-methyl group rather than in the direction opposite the methyl in the latter.…”

Structure revision of cryptosporioptides and determination of the genetic basis for dimeric xanthone biosynthesis in fungi

“…This structure contains an unusual ring-contracted xanthone which is difficult to rationalise biosynthetically, and an unprecedented N -malonyl aminal bridge. Further studies18 of this strain also led to the isolation of the corresponding free acid, named cryptosporioptide A 13 , and cryptosporioptide B 14 , which lacks the malonic acid ester amide bridge.…”