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Twelve compounds, including four undescribed cytochalasins, xylariachalasins A–D (1–4), four undescribed polyketides (5–8), and four known cytochalasins (9–12), were isolated from the mangrove endophytic fungus Xylaria arbuscula QYF. Their structures and absolute configurations were established by extensive spectroscopic analyses (1D and 2D NMR, HRESIMS), electronic circular dichroism (ECD) calculations, 13C NMR calculation and DP4+ analysis, single-crystal X-ray diffraction, and the modified Mosher ester method. Compounds 1 and 2 are rare cytochalasin hydroperoxides. In bioactivity assays, Compound 2 exhibited moderate antimicrobial activities against Staphylococcus aureus and Candida albicans with MIC values of 12.5 μM for both Compound 10 exhibited significant cytotoxic activity against MDA-MB-435 with an IC50 value of 3.61 ± 1.60 μM. [ABSTRACT FROM AUTHOR]

Five new polyketides, including two chromones (1–2), two phenyl derivatives (4–5), and a tandyukusin derivative (6), along with five known polyketides (3 and 7–10) were isolated from mangrove endophytic fungus Trichoderma lentiforme ML-P8-2. The planar structures of compounds were elucidated via detailed 1D, 2D NMR, and HR-ESI-MS analysis. ECD spectra, optical rotation values calculation, and alkali hydrolysis were applied in the determination of the absolute configuration of the new compounds. In bioassays, 6 and 9 exhibited promising antifungal activities against Penicillium italicum, with an MIC value of 6.25 μM for both compounds. Moreover, 3 displayed moderate AChE inhibitory activity with an IC50 value of 20.6 ± 0.3 μM. [ABSTRACT FROM AUTHOR]

Seven new polyketides, including four indenone derivatives, cytoindenones A–C (1, 3–4), 3′-methoxycytoindenone A (2), a benzophenone derivative, cytorhizophin J (6), and a pair of tetralone enantiomers, (±)-4,6-dihydroxy-5-methoxy-α-tetralone (7), together with a known compound (5) were obtained from the endophytic fungus Cytospora heveae NSHSJ-2 isolated from the fresh stem of the mangrove plant Sonneratia caseolaris. Compound 3 represented the first natural indenone monomer substituted by two benzene moieties at C-2 and C-3. Their structures were determined by the analysis of 1D and 2D NMR, as well as mass spectroscopic data, and the absolute configurations of (±)-7 were determined on the basis of the observed specific rotation value compared with those of the tetralone derivatives previously reported. In bioactivity assays, compounds 1, 4–6 showed potent DPPH· scavenging activities, with EC50 values ranging from 9.5 to 16.6 µM, better than the positive control ascorbic acid (21.9 µM); compounds 2–3 also exhibited DPPH· scavenging activities comparable to ascorbic acid. [ABSTRACT FROM AUTHOR]

Mangrove endophytic fungi represent significant and sustainable sources of novel metabolites with unique structures and excellent biological activities, attracting extensive chemical investigations. In this research, two novel heterodimeric tetrahydroxanthones, aflaxanthones A (1) and B (2), dimerized via an unprecedented 7,7′-linkage, a sp3-sp3 dimeric manner, were isolated from the mangrove endophytic fungus Aspergillus flavus QQYZ. Their structures were elucidated through high resolution electrospray ionization mass spectroscopy (HRESIMS) and nuclear magnetic resonance (NMR) spectroscopy, the absolute configurations of them were determined by a single-crystal X-ray diffraction combined with calculated electronic circular dichroism (ECD) spectra and a 1D potential energy scan. These compounds were evaluated for antifungal activities in vitro and exhibited broad-spectrum and potential antifungal activities against several pathogenic fungi with minimum inhibitory concentration (MIC) values in the range of 3.13–50 μM. They also performed moderate antibacterial activities against several bacteria with MIC values in the range of 12.5–25 μM. This research enriched the resources of lead compounds and templates for marine-derived antimicrobial drugs. [ABSTRACT FROM AUTHOR]

• Five new polyketides isolated from mangrove endophytic fungus Fusarium proliferatum • Solved absolute configuration of polyketide 2 by X-ray single-crystal diffraction • Usage of 13C NMR calculation and DP4+ probability analysis in structure elucidation • Polyketide 4 exhibited potential IL-1β inhibitory activity Five undescribed polyketides, including two talaketide derivatives (1, 4), two asperpentenone derivatives (2, 3), one phomaligol derivative (5) together with one known compound (6) were obtained from mangrove endophytic fungus Fusarium proliferatum NSD-1. The constitution of compounds 1 – 5 were determined by HRESIMS, 1D and 2D NMR spectra. Their absolute configurations were established by single-crystal diffraction, calculated electronic circular dichroism spectra, hydrolysis reaction, 13C NMR calculation and DP4+ probability analysis. In bioassays, compounds 1 and 5 showed moderate cytotoxicity against cancer cell lines SW480 and A549. Moreover, compound 4 showed potential IL-1β inhibitory activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Three rare natural sulfonamide products, sargassulfamide A (1), together with two unreported sulfonamides pestasulfamides B (2) and A (3) were obtained from mangrove endophytic fungus Pestalotiopsis sp. HNY36-1D under the guidance of chemical and biological autoradiography. Their structures were determined by 1D and 2D NMR, HR-ESI-MS, as well as single crystal X-ray diffraction. It was noteworthy that sulfonamide derivatives were obtained from metabolites of fungi for the first time. In bioassay, compounds 1 and 3 showed moderate acetylcholinesterase (AChE) inhibitory activities with IC 50 values 28.41 and 11.94 μM, respectively. The structure-activity relationships (SARs) analysis suggested that the existence of hydrogen atom on the N atom of sulfonamide derivatives and the closed loop of cyclic dipeptide were beneficial to the activity. The molecular docking studies indicated that 1 and 3 were near the center of the active pocket of AChE, while 2 was at the edge of the protein due to the large steric hindrance. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new metabolites, furobenzotropolones A, B (1–2) with unusual benzene and dihydrofuran moieties and 3-hydroxyepicoccone B (3), together with seven known compounds (4–10) were obtained from the endophytic fungus Epicoccum nigrum MLY-3 isolated from the fresh leaf of mangrove plant Bruguiear gymnorrhiza collected from Zhuhai. Their structures were assigned by the analysis of UV, IR, NMR, and mass spectroscopic data. Compound 1 was further confirmed by single-crystal X-ray diffraction experiment using Cu Kα radiation. In antioxidant activities in vitro, compounds 2, 3, 5, and 8 showed promising DPPH· scavenging activity with IC50 values ranging from 14.7 to 29.3 µM. Compounds 2, 3, 5, 7, and 8 exhibited promising potent activity in scavenging ABTS· with IC50 values in the range of 18–29.2 µM, which was stronger than that of the positive control ascorbic acid (IC50 = 33.6 ± 0.8 µM). [ABSTRACT FROM AUTHOR]

One new diterpenoid, diaporpenoid A (1), two new sesquiterpenoids, diaporpenoids B–C (2,3) and three new α-pyrone derivatives, diaporpyrones A–C (4–6) were isolated from an MeOH extract obtained from cultures of the mangrove endophytic fungus Diaporthe sp. QYM12. Their structures were elucidated by extensive analysis of spectroscopic data. The absolute configurations were determined by electronic circular dichroism (ECD) calculations and a comparison of the specific rotation. Compound 1 had an unusual 5/10/5-fused tricyclic ring system. Compounds 1 and 4 showed potent anti-inflammatory activities by inhibiting the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW264.7 cells with IC50 values of 21.5 and 12.5 μM, respectively. [ABSTRACT FROM AUTHOR]

Four new steroids (1–4) were isolated from the mangrove endophytic fungus Phoma sp. SYSU-SK-7. Compounds 1–2, with an unusual aromatic B ring skeleton, exhibited potent anti-inflammatory and α -glucosidase inhibitory activities. Molecular docking studies were performed to investigate the interaction of compounds 1 and 2 with iNOS protein. • Four new steroids were isolated from the mangrove endophytic fungus Phoma sp. SYSU-SK-7. • Phomosterols A (1) and B (2) were characterized by an unusual aromatic B ring skeleton moiety. • Phomosterols A (1) and B (2) exhibited potent anti-inflammatory and α -glucosidase inhibitory activities. Four new steroids phomosterols A-B (1 – 2), phomopenes A-B (3 – 4) and one known analogue (5) were isolated from the mangrove endophytic fungus Phoma sp. SYSU-SK-7. Their structures and absolute configurations were determined via NMR data, single-crystal X-ray diffraction analysis, and ECD calculations. Compounds 1–2 contain an unusual aromatic B ring skeleton in sterols, and compound 1 represent the first crystal structure described. Compounds 1 , 2 and 5 showed inhibitory activities against nitric oxide (NO) production in lipopolysaccharides (LPS) induced RAW 264.7 cells with IC 50 values of 13.5, 25.0 and 12.5 μM, respectively. Then, the affinities between new bioactive compounds (1 and 2) with nitric oxide synthase (iNOS) were researched by molecular docking studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nine new azaphilone derivatives were isolated from the mangrove endophytic fungus Penicillium sclerotiorum ZJHJJ-18. • The absolute configurations of 1 – 9 were determined by ECD calculation and chemical transformations. • Compounds 3 – 5 exhibited significant inhibitory activities against NO production with IC 50 values ranging from 6.30 to 9.45 μM. • Molecular docking study implied the probable binding interaction of bioactivity compounds 3 – 5 with inducible nitric oxide synthase (iNOS). Nine undescribed azaphilone derivatives, sclerazaphilones A–H (1 – 9), and three known analogues (10 – 12), were obtained and identified from the fermented rice cultures of a mangrove endophytic fungus Penicillium sclerotiorum ZJHJJ-18. 1D and 2D NMR, HRESIMS and spectral data indicated the chemical structures of 1 – 9 , and their absolute configurations were assigned by experimental and computational analyses of electronic circular dichroism (ECD) spectra, and application of the chemical transformations. Compounds 1 – 4 were the first reported N -containing azaphilone derivatives with 5/6 dicyclic core. The bioassay results showed that compounds 3 – 5 exhibited effective inhibitory effects on the nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with IC 50 values in the range of 6.30–9.45 μM. Moreover, a molecular docking study was conducted to investigate the probable binding interaction of 3 – 5 with inducible nitric oxide synthase (iNOS). [ABSTRACT FROM AUTHOR]

• Eight new sesquiterpenoids (2 , 4 – 6 and 10 – 13) were isolated from the fungus Phomopsis sp. SYSU-QYP-23. • The absolute configuration of the side chain in compound 1 was first defined by modified Mosher's method. • Compounds 1 – 7 exhibited potent inhibitory activities against NO production with IC 50 values ranging from 8.6 to 14.5 μM. • Molecular docking studies implied the probable binding interaction of bioactivity of compounds 1 – 9 with nitric oxide synthase (iNOS). Eight new sesquiterpene derivatives (2 , 4 – 6 and 10 – 13), along with five known analogues were isolated from the mangrove endophytic fungus Phomopsis sp. SYSU-QYP-23. Their structures of new compounds were established by spectroscopic methods, and the absolute configurations were confirmed by single-crystal X-ray diffraction analysis and comparison of the experimental ECD spectra. The absolute configuration of the side chain in 1 was first defined by modified Mosher's method. Compounds 1 – 7 showed potent inhibitory activities against nitric oxide (NO) production in lipopolysaccharides (LPS) induced RAW 264.7 cells with IC 50 values ranging from 8.6 to 14.5 μM. The molecular docking results implied that the bioactive sesquiterpenes may directly bind with targeting residues in the active cavity of iNOS protein. [ABSTRACT FROM AUTHOR]

• Six new compounds (±)- 1, (±)- 2, 3 and 8 were isolated from the mangrove endophytic fungus Phomopsis sp. SYSUQYP-23. • The absolute configurations of (±)- 1 , (±)- 2 and 8 were determined by ECD calculation. • Compounds 3 – 9 exhibited significant inhibitory activities against NO production with IC 50 values ranging from 4.5 to 25.0 μM. • Molecular docking study implied the probable binding interaction of bioactivity compounds 4 and 5 with nitric oxide synthase (iNOS). Five new maleimide derivatives, (+)- and (−)- farinomalein F (1), (+)- and (−)- farinomalein G (2), farinomalein H (3) and one new linearly fused prenylated indole alkaloid phomoamide (8), along with five known compounds 4 – 7 and 9 were isolated from the mangrove endophytic fungus Phomopsis sp. SYSUQYP-23. Their structures and absolute configurations were determined by HRESIMS, spectroscopic and electronic circular dichroism (ECD) calculations. Bioassay results showed that compounds 3 – 9 exhibited significant inhibitory activities against nitric oxide (NO) production in lipopolysaccharides (LPS) induced RAW 264.7 cells, with IC 50 values ranging from 4.5 to 25 μM. Moreover, the molecular docking study implied the probable binding interaction of compounds 4 and 5 with nitric oxide synthase. [ABSTRACT FROM AUTHOR]