Bistachybotrysins D and E,one stereoisomeric pair of cytotoxic phenylspirodrimane dimers from Stachybotrys chartarum

Bistachybotrysins D and E (1 and 2), one stereoisomeric pair of phenylspirodrimane dimers, were isolated from Stachybotrys chartarum CGMCC 3.5365. They represent novel phenylspirodrimane dimers with a central [6,5,6]-tricyclic carbon scaffold containing a cyclopentanone core. The structures of 1 and 2 were elucidated through extensive spectroscopic data analysis, and their absolute configurations were characterized by calculated electronic circular dichroism (ECD). Compounds 1 and 2 displayed potent cytotoxic activity against the four human tumor cell lines HCT116, BGC823, Daoy and HepG2 with IC_ (50)values ranging from 6.7 μmol/L to 11.6 μmol/L. Furthermore, a plausible biogenetic pathway for 1 and 2 is proposed.

红树林植物内生真菌Stachybotrys chartarum HDN16-358次级代谢产物研究

目的对红树林植物内生真菌Stachybotrys chartarum(HDN16-358)进行次级代谢产物的研究。方法利用薄层色谱层析(TLC)、反相ODS、Sephadex LH-20、半制备型HPLC等色谱学方法对菌株的乙酸乙酯粗提物进行分离纯化;利用NMR、MS、UV等波谱学技术手段,解析确定化合物的结构,并对化合物1进行了细胞毒活性筛选。结果分离鉴定了5个单体化合物:(2S)-5-Hydroxy-2,7-dimethyl-2-(4,8-dimethyl-3E,7-nonadienyl)-2H-chromene-6-carbaldehyde(1)、BR-011 (2)、LL-Z 1272β(3)、stachybotrylactone (4)、5-Methylbenzene-1,3-diol(5)。结论红树林植物内生真菌是活性物质的重要来源。从红树林植物内生真菌Stachybotrys chartarum HDN16-358中分离得化合物1~5,其中化合物1首次从自然界中分离得到,其具有中等强度的细胞毒活性。

Fibrinolytic Evaluation of Compounds Isolated from a Marine Fungus Stachybotrys Iongispora FG216

As a part of our continuing work to discover bioactive leading molecules from marine microorganism, ethyl acetate fraction of organic extract of the train Stachybotrys longispora FG216 showed fibrinolytic activity in our primary screen. The bioassay-guided purification of the active fractions resulted in isolation of a new isoindolone, FGFC2 （1） （FGFC2, Fungi fibrinolytic compound 2）, together with two known compounds, LL-Zl272β （2） and ergosterol （3）. The structure of compound 1 was elucidated by the spectral analysis of 1D （^1H, ^13C） NMR, 2D （COSY, HSQC, and HMBC） and ESI-MS. Three compounds were evaluated for fibrinolytic activities in vitro. Compared to FGFC1 （EC50=47 μmol/L） as a reference drug, compound 1 and ergosterol （3） showed moderate fibrinolytic activities in vitro with EC50 values of 108.16 and 156.30 μmol/L, respectively. LL-Z127213 （2） had no fibrinolytic activity.

Identification and Fibrinolytic Evaluation of an Isoindolone Derivative Isolated from a Rare Marine Fungus Stachybotrys Iongispora FG216

An isoindolone derivative, Fungi fibrinolytic compound （R）-2,5-bis（（2R,3R）-2-（（E）-4,8-dimethylnona-3,7-dien- 1-y1）-3,5-dihydroxy-2-methy--7-oxo-3,4,7,9-tetrahydr pyrano[2,3-e]isoindol-8（2H）-yl）pentanoic acid （FGFC1, Fungi fibrinolytic compound 1）, was isolated from a rare marine microorganism strain Stachybotrys longispora FG216. The structure of FGFC1 was elucidated by 1H NMR, 13C NMR, IR, and MS data; moreover, it was also evaluated for fibrinolytic activity in vitro and in vivo. The results showed that 0.1--0.4 mmol/L of FGFC1 could stimulate generation of plasmin activity （increased by 2.05--11.44 folds） by measuring Glu-plasminogen and Lys-plasminogen activation in vitro. The experiment of fluorescein isothiocyanate （FITC）-fibrinogen degradation indicated that the effect of FGFCI on fibrinolytic activity was mediated by plasminogen and scuPA. In addition, FGFC 1 （10 mg/kg） could dissolve most of pulmonary thrombus of Wistar rat in vivo. It is possible that FGFC 1 is a potential thrombolytic agent in the future.

Distachydrimanes A-F,phenylspirodrimane dimers and hybrids with cytotoxic activity from the coral-derived fungus Stachybotrys chartarum

By integrating one strain-many compounds(OSMAC)and LC-MS-based molecular networking strategies,distachydrimanes A-F(1-6),six novel phenylspirodrimane dimers and hybrids representing two types of unprecedented terpenoid-polyketide hybrid skeletons,were isolated from the modified fermented rice substrate of a coral-derived fungus Stachybotrys chartarum.All the structures incorporating their absolute configurations were elucidated based on comprehensive spectroscopic analyses,mainly including HRESIMS and NMR data,single-crystal X-ray diffraction(Cu Kα),and comparison of the experimental electronic circular dichroism(ECD)data.Architecturally,compounds 1-6 represent an unprecedented class of dimeric phenylspirodrimanes with an unexpected C-18-C-23′linkage,of which compounds 1-3 also feature an unexpected 5-methyl-1,3-benzenediol moiety via a carbon-carbon linkage.The bioactivity assay demonstrated that compounds 1,5 and 6 induced cell proliferation inhibition,G0/G1 cell cycle arrest,senescence and mitochondrial-mediated apoptosis in L1210 cells,highlighting their potentials as a new category of anticancer agents.

Structural diversification of phenylspirodrimane lactams by employing a biosynthetic intermediate

Phenylspirodrimanes are a kind of meroterpenoids with structural diversity and complexity,exhibiting a wide of biological properties,especially for the lactam derivatives consisting a y-lactam moiety and N-linked side chains.These compounds were derived from multi-step combination of enzymatic and non-enzymatic conversions of intermediates in their biosynthetic pathways.Stachbotrydial(2)with an o-phthalaldehyde unit was supposed as the high-reactivity intermediate of phenylspirodrimane lactams via nonenzymatic reaction with amines.In the present work,an effective and non-enzymatic diversification strategy was developed for the structural diversification of phenylspirodrimane lactams including monomers and dimers from 2 by feeding structurally various mono-and diamines in the fungus Stachybotrys chartarum cultures.In total,24 phenylspirodrimane lactams(1,3-25)including 18 new compounds were synthesized.Among them,stachybocin A(1),a bioactive phenylspirodrimane lactam dimer,was produced with the yield of 18.7 mg/g of cell dry weight.The structures of these compounds were elucidated by extensive spectroscopic data,single-crystal X-ray diffraction(Cu Kα),and calculated electronic circular dichroism(ECD)analyses.Bioassay revealed that compounds 1,17,and 24 displayed significant inhibitory effect on the inactivated state of hNav 1.2 channels with IC_(50) values of 0.22,2.08,and 0.53μmol/L,respectively.In addition,1 showed potent protein tyrosine phosphatase 1B(PTP1B)inhibitory N-methyl-b-aspartate(NMDA)receptor antagonistic,and anti-inflammatory activities.

内生真菌Ⅸ.中国地衣内生真菌3个丝孢菌新记录种(英文)

在云南紫溪山地衣内生真菌多样性研究中,从地衣组织中分离到3个中国丝孢菌新记录种Memnoniella subsimplex,Nigrospora sacchari和Stachybotrys atra。本文进行了重新描述与图解。菌株保藏在本课题组。