Abstract:
Guided by molecular networking, HSQC-based DeepSAT, and SMART analyses, a chemical investigation of the coral-derived fungus
Talaromyces sp. TJ403-AL05 led to the isolation and identification of taladipyrones A−I (
1−
9), a series of new
α-pyrone dimers with four distinct skeletons. Among these, compounds
1 and
9 represented two unprecedented classes of rearranged
α-pyrone dimers, and compounds
5−
7 were the first talarolactone-type dimers obtained as racemates. Extensive spectroscopic analysis, quantum chemical calculations, and X-ray diffraction analysis were used to determine their structures, including each enantiomer of racemic compounds
5−
8 after chiral HPLC resolution. In human cardiomyocytes (AC16), compounds
1−
6 and
8−
9 attenuated injury caused by 24 h cold ischemia (CI) at 40 µmol·L
−1. Moreover, compound
2 could improve CI-induced disruption of redox homeostasis
via activation of the PI3K/AKT signaling pathway, representing the first fungal polyketide with such cardioprotective activity.