Absolute configurations of talaromycones A and B, α-diversonolic ester, and aspergillusone B from endophytic Talaromyces sp. ECN211

Abstract

Talaromycones A (1) and B (2), new xanthenediones, were isolated from the cultures of Talaromyces sp. ECN211, an endophytic fungus, along with α-diversonolic ester (3), aspergillusone B (4), glauconic acid (5), and rosellisin (6). The planar structures of 1 and 2 were elucidated by extensive spectroscopic analyses. Furthermore, the absolute configurations of 1–4 were determined by single-crystal X-ray diffraction and electronic circular dichroism spectroscopy (ECD). In addition, the crystallographic data for 5 were updated for the first time in over 50 years.

Keywords

• absolute configuration
• endophytic fungus
• glauconic acid
• talaromyces
• tetrahydroxanthone
• xanthenedione