Xia-Nan Sang

Phomeketales A–F, six unique metabolites from the endophytic fungus Phoma sp. YN02-P-3

Phomeketales A–F (1–6), six new xyloketals, with unprecendented carbon substitution at C-16 and C-17 simultaneously, were isolated from the endophytic fungus Phoma sp. YN02-P-3. Their structures were elucidated on the basis of 1D and 2D NMR spectral data and ECD analysis. Compound 3 exhibited moderate anti-AChE activity and cytotoxicity against HL-60.

C21 steroidal glycosides from the roots of Cynanchum paniculatum

As a part of our continuing research for bioactive constituents from Cynanchum plants, four new C21 steroidal glycosides, cynapanoside D-G (1-4), together with six known compounds (5-10) were isolated from the roots of Cynanchum paniculatum (Bge.) Kitag. Their structures were elucidated on the basis of 1D- and 2D-NMR spectroscopic data as well as HR-ESI-MS analysis. Compound 8 exhibited potent inhibitory activities against HL-60, HT-29, PC-3 and MCF-7 cell lines with IC50 values of 8.3, 7.5, 34.3 and 19.4μM, respectively and compounds 1-4 and 9 displayed moderate cytotoxicity against the four cell lines. The in vitro antioxidant activities of compounds 1-4, 8 and 9 were assayed by DPPH radical scavenging activity. Antibacterial and antifungal activities of compounds 1-4, 8 and 9 were also tested.

Lecanicillones A–C, three dimeric isomers of spiciferone A with a cyclobutane ring from an entomopathogenic fungus Lecanicillium sp. PR-M-3

Lecanicillones A–C (1–3), three unusual dimeric spiciferones with acyclobutane ring via a [2 + 2] cycloaddition, were isolated from an entomopathogenic fungus Lecanicillium sp. PR-M-3. The structures of 1–3 were elucidated on the basis of spectral data, single-crystal X-ray diffraction, and ECD analysis. Compounds 1 and 3 showed moderate cytotoxicity against the HL-60 cell line.

Two pairs of enantiomeric α-pyrone dimers from the endophytic fungus Phoma sp. YN02-P-3

(±) Phomones A (1) and B (2), two pairs of novel enantiomeric α-pyrone dimers from the endophytic fungus Phoma sp. YN02-P-3 are reported. Compounds 1 and 2 are the first examples of 6-α,β-unsaturated ester-2-pyrone dimers, and compound 1 possesses a novel 6/4/5/6 tetracyclic ring system. Their structures and stereochemistry were determined by the analysis of extensive spectroscopic data, ECD calculations and single-crystal X-ray diffraction data.

A novel 3,4-dihydronaphthalen-1(2H)-one with spiro-butyrolactone and a new isocoumarin isolated from the endophytic fungus Phoma sp. YN02-P-3

Abstract A novel 3,4-dihydronaphthalen-1(2H)-one with spiro-butyrolactone phomol (1) and a new isocoumarin phomasatin (2), together with two known compounds (3–4) were isolated from the solid culture of the endophytic fungus Phoma sp. YN02-P-3. Their structures including the absolute configurations were characterized on the basis of extensive 1D, 2D NMR (HSQC, HMBC, NOESY), MS, and CD spectral data. Compound 1 showed selective cytotoxic activity against HL-60 cell line with the IC50 value of 29.05 μM.

α-Pyrone derivatives with cytotoxic activities, from the endophytic fungus Phoma sp. YN02-P-3

Four new α-pyrone derivatives phomones C-F (1-4) together with four known compounds (5-8) were isolated from the endophytic fungus Phoma sp. YN02-P-3. Compound 1 is the first example of 6-α,β-unsaturated ester-2-pyrone dimers via intermolecular symmetrical [2+2] cycloaddition. The chemical structures of these compounds were determined from spectroscopic data (1D/2D NMR, MS and IR). The acetylated product (9) of 1 along with compounds 1-8 were then tested for their cytotoxicity against HL-60, PC-3 and HCT-116 cell lines. Compounds 2, 3, 5 and 9 with acetyl groups showed significant inhibitory activities against the three cell lines with IC50 values in the range 0.52-9.85μM. while compounds 1, 4 and 6-8 that possess no acetyl group showed no inhibitory activity (IC50>50μM), indicating that the acetyl group at 10- or 12- are essential for their cytotoxic activities. The structure-activity relationships of these phomones were also reported.

C21 steroidal glycosides from Cynanchum taihangense

Abstract Two new C21 steroidal glycosides, cynataihosides E (1) and F (2), together with a known one, sublanceoside H2 (3), were isolated from Cynanchum taihangense. The aglycone of cynataihoside F (2) was also a new compound. Their structures were elucidated on the basis of NMR spectroscopic data, HR-ESI-MS analysis, and chemical evidence. Their cytotoxic activities against three human tumor cell lines (HL-60, THP1, and Caco2) were reported. Graphical Abstract

Three new tetralol analogs from soil-derived fungus Myrothecium verrucaria with anti-inflammatory activity

Abstract Three new tetralol analogs, myrochromanols A-C (1–3), together with 11 known trichothecenes (4–14), were isolated from a soil fungus Myrothecium verrucaria HL-P-1. The structures of the three new compounds were elucidated by extensive spectroscopic analysis including HRESIMS, NMR, and ECD calculation. All of the new compounds were tested for their anti-inflammatory activity and cytotoxicity. Compounds 1 and 3 inhibited lipopolysaccharide (LPS)-induced NO production in BV2 cells with IC50 values of 26.04 and 25.80 μM, respectively. Three new tetralol analogs were isolated from a soil fungus Myrothecium verrucaria HL-P-1. All of them were tested for their anti-inflammatory and cytotoxicity activity.