Daldiniaeschsone A, a Rare Tricyclic Polyketide Having a Chromone Unit Fused to a <i>δ</i>-Lactone and Its Symmetrical Biphenyl Dimer, Daldiniaeschsone B, from an Endophytic Fungus <i>Daldinia eschscholtzii</i> SDBR-CMUNKC745

• Main Authors: Natnicha Wutthiwong, Virayu Suthiphasilp, Aknarin Pintatum, Nakarin Suwannarach, Jaturong Kumla, Saisamorn Lumyong, Tharakorn Maneerat, Rawiwan Charoensup, Sarot Cheenpracha, Thunwadee Limtharakul, Stephen G. Pyne, Surat Laphookhieo
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Journal of Fungi
• Subjects: <i>Daldinia eschscholtzii</i> SDBR-CMUNKC745; tricyclic polyketide; biphenyl dimer; chromone; <i>α</i>-glucosidase inhibitory activity
• Online Access: https://www.mdpi.com/2309-608X/7/5/358
• ISSN: 2309-608X

Daldiniaeschsone A (<b>1</b>), a rare tricyclic polyketide having a chromone unit fused to a <i>δ</i>-lactone and its symmetrical 6,6′-biphenyl dimer, daldiniaeschsone B (<b>2</b>), together with three known compounds (<b>3</b>−<b>5</b>), were isolated from a plant-derived endophytic fungus, <i>Daldinia eschscholtzii</i> SDBR-CMUNKC745. Their structures were elucidated by extensive 1D and 2D NMR spectroscopic data and HRESIMS. All compounds showed <i>α</i>-glucosidase inhibitory activity with IC₅₀ values ranging from 0.16−0.85 mM and compound <b>1</b> was the best <i>α</i>-glucosidase inhibitory activity (IC₅₀ = 0.16 mM).