New secondary metabolites with immunosuppressive and BChE inhibitory activities from an endophytic fungus Daldinia sp. TJ403-LS1.

Abstract Five new acetylenic phenol derivatives (1–4 and 7), one new benzofuran derivative (8), one new naphthol derivative (9), and two known analogues (5 and 6), were isolated and identified from an endophytic fungus Daldinia sp. TJ403-LS1 that was isolated from the medicinally valuable plant Anoectochilus roxburghii. Their structures were elucidated by means of extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. In addition, compound 1 exhibited remarkable immunosuppressive activity against LPS and anti-CD3/anti-CD28 mAbs activated murine splenocytes proliferation with the same IC50 values of 0.06 μM and BChE inhibitory activity with an IC50 value of 6.93 ± 0.71 μM, and compounds 6, 8 and 9 showed excellent BChE inhibitory activity with IC50 values of 16.00 ± 0.30, 23.33 ± 0.55, and 15.53 ± 0.39 μM, respectively (positive drug neostigmine, IC50 = 49.60 ± 6.10 μM), highlighting the promising potentials to be designed and developed as immunosuppressive and BChE inhibitory agents.