Heterodimers of Aromadendrane Sesquiterpenoid with Benzoquinone from the Chinese Liverwort Mylia nuda.

Mylnudones A-G (1-7), unprecedented 1,10-seco-aromadendrane-benzoquinone-type heterodimers, and a highly rearranged aromadendrane-type sesquiterpenoid (8), along with four known analogs (9-12), were isolated from the liverwort Mylia nuda. Compounds 1-6 and 7, bearing tricyclo[6.2.1.02,7] undecane and tricyclo[5.3.1.02,6] undecane backbones, likely formed via a Diels-Alder reaction and radical cyclization, respectively. Their structures were determined by spectroscopic analysis, computational calculation, and single-crystal X-ray diffraction analysis. Dimeric compounds displayed cytoprotective effects against glutamic acid-induced neurological deficits.

Asperunguisins A-F, Cytotoxic Asperane Sesterterpenoids from the Endolichenic Fungus Aspergillus unguis.

Six new asperane-type sesterterpenoids, asperunguisins A-F (1-6), were isolated from the endolichenic fungus Aspergillus unguis, together with a known analogue, aspergilloxide (7); these are rare asperane-type sesterterpenoids, characterized by a unique hydroxylated 7/6/6/5 tetracyclic system. The structures of asperunguisins A-F (1-6) were elucidated on the basis of spectroscopic methods (NMR and HRESIMS), X-ray single-crystal diffraction analysis, ECD calculations, and biogenetic considerations. Asperunguisin C (3) showed cytotoxicity against the human cancer cell line A549 with an IC50 value of 6.2 µM. Further investigation revealed that the observed cell death was a result of G0/G1 cell cycle arrest via DNA damage followed by cellular apoptosis.

Cytotoxic p-Terphenyls from the Endolichenic Fungus Floricola striata.

Eleven new p-terphenyls, floricolins K-U (1-11), together with 13 biosynthetically related known compounds (12-24) were isolated from an endolichenic fungus, Floricola striata. Their structures were elucidated by extensive spectroscopic analyses and single-crystal X-ray diffraction measurements. The newly isolated p-terphenyls inhibited the growth of A2780, MCF-7, and A549 cell lines. Further evaluation for the multidrug resistance (MDR) reversal activity of compound 5 revealed it enhanced the sensitivity of MCF-7/ADR cells toward adriamycin 39-fold at 10 µM through modulating P-glycoprotein-mediated drug exclusion.

Two new α-pyrone derivatives from an endolichenic fungus Tolypocladium sp.

Two new α-pyrone derivatives, tolypocladones A (1) and B (2), together with five known compounds were isolated from an endolichenic fungus Tolypocladium sp. (4259a). The structures of all the compounds were determined by analysis of their MS and NMR data. Among them, compound 1 was an enantiomeric mixture and the configuration was established by single-crystal X-ray diffraction analysis using Cu-Kα radiation. Also, this is the first report of the presence of compound 3 (glycine, N-(2,3-dihydroxybenzoyl)-methyl ester) and compound 4 (2H-pyran-2-one, 4-methoxy-6-(1,3-pentadienyl)) as natural products.

p-Terphenyl Derivatives from the Endolichenic Fungus Floricola striata.

Ten new p-terphenyl derivatives, floricolins A-J (1-10), together with six known compounds (11-16), were isolated from the extract of the endolichenic fungus Floricola striata. Chemical structures of these compounds were elucidated using spectroscopic data (HRESIMS and NMR). Among them, 9 and 10 were enantiomeric mixtures, and their configurations were established by single-crystal X-ray diffraction analysis using Cu Kα radiation. Evaluation of the isolated compounds against Candida albicans revealed that the most active compound, 3 (MIC 8 µg/mL), exerted fungicidal action by destruction of the cell membrane.

A new diketopiperazine heterodimer from an endophytic fungus Aspergillus niger.

One new diketopiperazine heterodimer, asperazine A (1), and eight known compounds, asperazine (2), cyclo(d-Phe-l-Trp) (3), cyclo(l-Trp-l-Trp) (4), 4-(hydroxymethyl)-5,6-dihydro-pyran-2-one (5), walterolactone A (6), and campyrones A-C (7-9), were isolated from an endophytic fungus Aspergillus niger. Their structures were determined unequivocally on the basis of extensive spectroscopic data analysis. This is the first report of the presence of compound 3 as a natural product. Cytotoxicity test against human cancer cell lines PC3, A2780, K562, MBA-MD-231, and NCI-H1688 revealed that compounds 1 and 2 had weak activities.

[Chemical Constituents from Rhizome of Valeriana jatamansi].

OBJECTIVE: To study the chemical constituents from the rhizome of Valeriana jatamansi. METHODS: The chemical constituents were separated and purified by silica gel, medium pressure column chromatography, and preparative HPLC. Their structures were determined by physicochemical properties and spectral data. RESULTS: Six compounds were isolated from the dibromochloromethane extract in the rhizome of Valeriana jatamansi, and identified as decursidin (1), decursitin B (2), decursitin A (3), 3'(S)-acetoxy-4'(R)-angeloyloxy-3',4'-dihydroxanthyletin (4), 8-acetoxyl-pathchouli alcohol (5) and dibutyl phthalate (6). CONCLUSION: Compounds 1-4 are coumarins which are isolated from this genus for the first time,and compound 6 is isolated from this genus for the first time.

Two New Quinazoline Derivatives from the Moss Endophytic Fungus Aspergillus sp. and Their Anti-inflammatory Activity.

Two new quinazoline derivatives versicomides E (1) and F (2), and 10 known compounds (3-12) were isolated from the moss endophytic fungus Aspergillus sp. Their structures were determined on the basis of extensive spectroscopic data analysis and ECD calculations. Among them, the compound 7 (6-hydroxy-3-methoxyviridicatin) was first reported as a natural product. Inhibition on LPS-induced NO production in RAW 264.7 murine macrophages found that compounds 5, 7 and 8 showed significant inhibitory effects on NO production, with IC50 values of 49.85, 22.14 and 46.02 µM respectively.

Combining NMR-Based Metabolic Profiling and Genome Mining for the Accelerated Discovery of Archangiumide, an Allenic Macrolide from the Myxobacterium Archangium violaceum SDU8.

An unprecedented 19-membered allenic macrolide archangiumide (1) was discovered from the myxobacterium Archangium violaceum SDU8 by integrating NMR-based metabolic profiling and genome mining. Its biosynthesis pathway was proposed based on the architectural analysis of the encoding trans-AT PKS genes and validated by isotope labeling. The methodology of combing 2D NMR-based metabolic profiling and bioinformatics-aided structure prediction, as exemplified by this study, is anticipated to improve discovery efficiency of a broader range of microbial "dark matter".

[Epidemiological survey of congenital heart disease among people aged from 4 to 18 in Haidong area of Qinghai province].

OBJECTIVE: To investigate the epidemiological characteristics of congenital heart disease (COHD) among 4 to 17 years old children in Haidong area of Qinghai province. METHODS: All 97 718 children were surveyed with the following 3 steps: prescreening, countershock and confirmation with color Doppler. The distribution patterns were analyzed by national groups, ages and genders respectively. RESULTS: There were 496 COHD cases detected. The total incidence was 5.076 per thousand (496/97 718). The incidences of male and female were 5.046 per thousand (256/50 730) and 5.108 per thousand (240/46 988) (chi(2) = 0.018, P > 0.05). There was a significant difference between Pingan county and the others (chi(2) = 10.62, P < 0.01). The highest incidence was in Ledu (5.46 per thousand), the incidences of Huzhu and Pingan county were 5.45 per thousand and 3.64 per thousand respectively. There was no significant difference among different national groups (chi(2) = 0.33, P > 0.05). Among 496 COHD cases, the ratio of atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA) were 37.30%, 35.69% and 22.18% respectively. CONCLUSION: Total incidence of COHD was 5.076 per thousand in Haidong area of Qinghai province. The incidence was not different in both genders and national groups. The constitution of COHD in different counties were different.

Secondary metabolites from the endolichenic fungus Ophiosphaerella korrae.

The isolation of the cytotoxic fractions from the endolichenic fungus Ophiosphaerella korrae yielded six new metabolites, including five polyketides (ophiofuranones A (1) and B (2), with unusual furopyran-3,4-dione-fused heterocyclic skeletons, ophiochromanone (3), ophiolactone (4), and ophioisocoumarin (5)), one sesquiterpenoid ophiokorrin (10), and nine known compounds. Their structures were established on the basis of the analysis of HRESIMS and NMR spectroscopic data. ECD calculations, GIAO NMR shift calculations and single-crystal X-ray diffraction were employed for the stereo-structure determination. A plausible biogenetic pathway for the ophiofuranones A (1) and B (2) was proposed. The cytotoxic assay suggested that the five known perylenequinones mainly contributed to the cytoxicity of the extract. Further phytotoxic studies indicated that ophiokorrin inhibited root elongation in the germination of Arabidopsis thaliana with an IC50 value of 18.06 µg mL-1.

Diterpenoids from the Chinese liverwort Frullania hamatiloba and their Nrf2 inducing activities.

Six previously undescribed labdane diterpenoids, frullanians A-F, along with five known diterpenoids, were isolated from the Chinese liverwort Frullania hamatiloba Stephani. Their structures were determined using NMR data, electronic circular dichroism (ECD) calculations as well as the single crystal X-ray diffraction measurement. NAD(P)H: QR (quinone reductase) assay demonstrated that frullanian D and four known compounds displayed antioxidant effect mediated via Nrf2 (Nuclear factor-erythroid 2-related factor 2) induction. Further investigation of the most bioactive frullanian D in MOVAS cells revealed that it ameliorated H2O2-induced oxidative insults without toxicity by increasing cell viability, attenuating morphological changes, and reducing intracellular ROS production. In addition, frullanian D promoted the nuclear translocation of Nrf2 and upregulated the expressions of antioxidant proteins NQO1 (NAD(P)H quinone oxidoreductase 1) and γ-GCS (γ-glutamyl cysteine synthetase). Docking analysis using MOE software further supported the activation of the Nrf2 pathway by frullanian D.