p-Terphenyl and Diterpenoid Metabolites from Endophytic Aspergillus sp. YXf3

Abstract

Six new p-terphenyl derivatives, named 4″-deoxy-3-hydroxyterphenyllin (1), 4″-deoxy-5'-desmethyl-terphenyllin (2), 5'-desmethylterphenyllin (3), 4″-deoxycandidusin A (4), 4,5-dimethoxycandidusin A (5), and terphenolide (6), four new diterpenoids with norcleistanthane (aspergiloid A (12) and aspergiloid B (13)), cleistanthane (aspergiloid C (14)), and isopimarane (aspergiloid D (15)) type skeletons, and five known p-terphenyl compounds (7-11) were isolated from the fermentation broth of the plant endophytic fungus Aspergillus sp. Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison of their NMR data with those reported in the literature. Compounds 4, 6, 7, and 9 displayed moderate neuraminidase inhibitory activity with IC(50) values ranging from 4.34 to 9.17 μM.

Cytotoxic Terphenyl Neolignans from Fungus Terana coerulea: New Natural Corticins D and E, and Revised Structure for Corticin A

“…[11] but in its p-quinol or leuco-form as occurs with corticin A described by Briggs et al [6]. This structure was confirmed by two-dimensional NMR experiments performed in the present work and also by comparison with other natural products described in the literature as candidusins [12]. The chemical shifts found for the methoxy groups and their comparison with 4''-deoxycandidusin A and 4,5dimethoxycandidusin A [12] confirmed that two of the three methoxy groups were the substituents at C-8 and C-8'.…”

“…This structure was confirmed by two-dimensional NMR experiments performed in the present work and also by comparison with other natural products described in the literature as candidusins [12]. The chemical shifts found for the methoxy groups and their comparison with 4''-deoxycandidusin A and 4,5dimethoxycandidusin A [12] confirmed that two of the three methoxy groups were the substituents at C-8 and C-8'. The HMBC correlations between these methoxy groups at  4.34 and 4.31 ppm with the two quaternary aromatic carbon signals at  134.5 ppm agree with the same p-dimethoxybenzenic ring present in candidusin derivatives.…”

Metabolomic Tools to Assess the Chemistry and Bioactivity of Endophytic Aspergillus Strain

“…Compounds 83, 84, 85, and 88 exhibited moderate neuraminidase inhibitory activity and thus may work as antiviral agents. [67] Aspergillus tubingensis (GX1-5E), a mangrove endophyte, produced three dimeric naphtho-c-pyrones, named rubasperone A (95), rubasperone B (96), and rubasperone C (97). Moreover, two compounds, rubrofusarin (98) and rubrofusarin B (99), were also isolated.…”

“…YXf3 from the leaf of Ginkgo biloba produced six p ‐terphenyl derivatives, 4″‐deoxy‐3‐hydroxyterphenyllin ( 80 ), 4″‐deoxy‐5′‐desmethylterphenyllin ( 81 ), 5′‐desmethylterphenyllin ( 82 ), 4″‐deoxycandidusin A ( 83 ), 4,5‐dimethoxycandidusin A ( 84 ), and terphenolide ( 85 ), five previously known p ‐terphenyl compounds ( 86 – 90 ), and four previously undescribed diterpenoids with norcleistanthane (aspergiloid A ( 91 ) and aspergiloid B ( 92 )), cleistanthane (aspergiloid C ( 93 )), and isopimarane (aspergiloid D ( 94 )) type skeletons. Compounds 83 , 84 , 85 , and 88 exhibited moderate neuraminidase inhibitory activity and thus may work as antiviral agents …”

Isochromophilones from an endophytic fungus Diaporthe sp.

“…Azaphilone compounds had a wide range of bioactivities including cytotoxic, antifungal, antimicrobial, antioxidant and antiinflammatory activities, [4][5][6][7][8] and could be generally produced by Penicillium, Chaetomium and Monascus. 3 In the course of our search for novel and/or bioactive metabolites from microbes lived in special niche, 4,9,10 five azaphilones including three new isochromophilones X-XII (1-3) and two known compounds sclerotioramine (4) 11 and isochromophilone VI (5) 12 were isolated from the solid-substrate fermentation cultures of an endophytic fungus Diaporthe sp. The structures were identified on the basis of extensive spectroscopic methods.…”