Dewu Zhang

Periconiasins A–C, New Cytotoxic Cytochalasans with an Unprecedented 9/6/5 Tricyclic Ring System from Endophytic Fungus Periconia sp.

Periconiasins A-C (1-3), new cytochalasans with an unprecedented 9/6/5 tricyclic ring system, were isolated from the endophytic fungus Periconia sp. F-31. Their structures and absolute configurations were elucidated by extensive spectroscopic and X-ray crystallographic analyses. Their biosynthesis is proposed to occur from an unusual seven acetate/malonate polyketide backbone attached to one leucine moiety by a PKS-NRPS followed by Diels-Alder and other reactions. 1 and 2 showed significant cytotoxicity against human HCT-8 cancer cells.

Periconianone A, a new 6/6/6 carbocyclic sesquiterpenoid from endophytic fungus Periconia sp. with neural anti-inflammatory activity.

Periconianone A (1), a polyoxygenated sesquiterpenoid with a new 6/6/6 tricarbocyclic skeleton, and periconianone B (2) were isolated from the endophytic fungus Periconia sp. Their structures and absolute configurations were elucidated by extensive spectroscopic analyses, calculated ECD, and single-crystal X-ray diffraction (Cu Kα). The biosynthesis of the unusual six-membered carbonic ring of 1 was postulated to be formed through intramolecular aldol condensation. Compounds 1 and 2 showed significant neural anti-inflammatory activity.

Pericoannosin A, a Polyketide Synthase–Nonribosomal Peptide Synthetase Hybrid Metabolite with New Carbon Skeleton from the Endophytic Fungus Periconia sp.

Four new polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) hybrid metabolites, pericoannosin A (1), with an unusual hexahydro-1H-isochromen-5-isobutylpyrrolidin-2-one skeleton, and three cytochalasans, periconiasins D-F (2-4), were isolated from the endophytic fungus Periconia sp. F-31. Their structures and absolute configurations were elucidated through extensive spectroscopic analyses, calculated ECD, and single-crystal X-ray diffraction (Cu Kα). A possible biogenetic pathway is proposed. Compounds 1 and 4 showed anti-HIV activity with IC50s of 69.6 and 29.2 μM, respectively.

Studies on chemical constituents from Ilex pubescens

Two new phenolic glycosides, ilexpubsides A and B, along with four known lignan glycosides were isolated from the roots of Ilex pubescens. By spectral evidence, the structures of the new compounds were elucidated as 4-O-β-D-[6′-O-(4″-O-β-D-glucopyranosylvanilloyl)glucopyranosyl] vanillic acid (1) and syringinic 6′-O-β-D-xylopyranoside (2). The known compounds were identified to be liriodendrin (3), (-)-olivil (4), tortoside A (5) and (+)-cyclo-olivil (6). All compounds were first isolated from Ilex pubescens.

Stachybotrysins A–G, Phenylspirodrimane Derivatives from the Fungus Stachybotrys chartarum

Seven new phenylspirodrimane derivatives named stachybotrysins A-G (2-8), together with five known compounds (1, 9-12), were isolated from Stachybotrys chartarum CGMCC 3.5365. Stachybotrysin D (5) is the first reported example of a naturally occurring alcoholic O-sulfation of a phenylspirodrimane, and stachybotrysins F and G (7 and 8) are the first examples possessing an isobenzotetrahydrofuran ring with an acetonyl moiety attached. The structures of these compounds were elucidated on the basis of extensive spectroscopic data analysis and by comparison with reported data. The absolute configurations of 1-8 were determined by X-ray single-crystal diffraction, electronic circular dichroism (ECD), and calculated ECD. Compounds 1 and 8 displayed anti-HIV activity with IC50 values of 15.6 and 18.1 μM, respectively, and 2, 7, 9, and 11 showed inhibitory effect on influenza A virus with IC50 values ranging from 12.4 to 18.9 μM.

Metabolites from the Plant Endophytic Fungus Aspergillus sp. CPCC 400735 and Their Anti-HIV Activities

Thirty-three metabolites including five phenalenone derivatives (1-5), seven cytochalasins (6-12), thirteen butenolides (13-25), and eight phenyl derivatives (26-33) were isolated from Aspergillus sp. CPCC 400735 cultured on rice. The structures of all compounds were elucidated by NMR, MS, and CD experiments, of which 1-5 (asperphenalenones A-E), 6 (aspochalasin R), and 13 (aspulvinone R) were identified as new compounds. Specifically, asperphenalenones A-E (1-5) represent an unusual structure composed of a linear diterpene derivative linked to a phenalenone derivative via a C-C bond. Compounds 1, 4, 10, and 26 exhibited anti-HIV activity with IC50 values of 4.5, 2.4, 9.2, and 6.6 μM, respectively (lamivudine 0.1 μM; efavirenz, 0.4 × 10-3 μM).

Oxazole-Containing Diterpenoids from Cell Cultures of Salvia miltiorrhiza and Their Anti-HIV-1 Activities

Four new oxazole-containing diterpenoids, salvianans A-D (1-4), along with three known diterpenoids (5-7), were isolated from Salvia miltiorrhiza cell cultures. The structures of the new compounds were elucidated using spectroscopic methods and single-crystal X-ray diffraction. The evaluation for their anti-HIV-1 activities revealed that 2 and 3 displayed inhibitory activities with IC50 values of 0.03 and 1.2 μM, respectively. The time of addition (TOA) assay and long terminal repeat (LTR) luciferase reporter assay results indicated that compound 2 was an HIV-1 transcription inhibitor and might be a lead compound of antiviral agents acting on HIV-1 transcription.

Peniazaphilin A, a new azaphilone derivative produced by Penicillium sp. CPCC 400786

A new azaphilone derivative, named peniazaphilin A (1) and one known isocoumarin, (R)-3-methyl-6-hydroxy-8-methoxy-3,4-dihydroisocoumarin (2) were isolated from the fungus Penicillium sp. CPCC 400786. Their structures were elucidated by means of extensive spectroscopic analysis. The absolute configuration of 2 was established by circular dichroism for the first time. Compounds 1 and 2 exhibited weak anti-HIV activities with the IC50 values of 60.4 and 69.3 μM, respectively.

Roseomonas globiformis sp. nov., an airborne bacteria isolated from an urban area of Beijing

A novel dark pink pigmented bacterium, designated strain CPCC 100847T (deposited with strain code 0113-15), was isolated from the urban air of Beijing, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CPCC 100847T was related to members of the genus Roseomonas and had the highest 16S rRNA gene sequence similarity to Roseomonas aestuarii JC17T (97.5 %). A low level of DNA-DNA relatedness (18.7 %) with its closest type strain R. aestuarii JC17T (KCTC 22692T) proved that strain CPCC 100847T belonged to a unique genomic species. CPCC 100847T had many common characteristics of the genus Roseomonas, but also had a range of cultural, physiological and biochemical characteristics that separated it from related Roseomonas species. Cells were Gram-negative, cocci- to oval-shaped, non-motile, non-endospore-forming and strictly aerobic. The respiratory ubiquinone was Q-10. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminolipid and an unidentified phospholipid. The major fatty acids (>5 %) were C18 : 1ω7c, anteiso-C15 : 0, C16 : 0, iso-C15 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The combined genotypic and phenotypic data indicated that the isolate represents a novel species of the genus Roseomonas. The name proposed for this species is Roseomonasglobiformis sp. nov., with CPCC 100847T (=KCTC 52094T) as the type strain. The DNA G+C composition is 65.2 mol%.

Four new monoterpenoids from an endophytic fungus Periconia sp. F-31

Abstract Five monoterpenoids were isolated from the endophytic fungus Periconia sp. F-31, including three new carene-type monoterpenoids, 2-carene-5,8-diol (1), 2-carene-8,10-diol (2), 2-carene-8-acetamide (3), one new menthene-type monoterpenoid 8-hydroxy-1,7-expoxy-2-menthene (4), and one known monoterpenoid anethofuran (5). The structures of all compounds were elucidated based on a comprehensive spectroscopic data analysis, electronic circular dichroism (ECD), and calculated ECD.