Talarolutins A–D: Meroterpenoids from an endophytic fungal isolate of Talaromyces minioluteus

Abstract

Four meroterpenoids [talarolutins A–D] and one known compound [purpurquinone A] were characterized from an endophytic fungal isolate of Talaromyces minioluteus (G413), which was obtained from the leaves of the medicinal plant milk thistle [Silybum marianum (L.) Gaertn. (Asteraceae)]. The structures of talarolutins A–D were determined by the analysis of various NMR and MS techniques. The relative and absolute configuration of talarolutins A was determined by X-ray diffraction analysis. A combination of NOESY data and comparisons of ECD spectra were employed to assign the relative and absolute configuration of the other analogues. Talarolutins B–D were tested for cytotoxicity against human prostate carcinoma (PC-3) cell line, antimicrobial activity, and induction of quinone reductase; no notable bioactivity was observed in any assay.

Assessing Genotypic and Environmental Effects on Endophyte Communities of Fraxinus (Ash) Using Culture Dependent and Independent DNA Sequencing

“…Some of the seed endophytes have also been reported in other plants including ash. Harzia acremonioides was reported from syptomatic ash petiole in northwestern Spain [ 60 ]; Diplodia mutila (= Botryosphaeria stevensii ) has also been reported from twigs of Vitis vinifera [ 61 ]; Volutella ciliata has been reported as a culturable endophyte from roots of Pinguicula vulgaris [ 62 ]; Paraconiothyrium brasiliense was reported for the first time from Chinese maple leaves [ 63 ]; Talaromyces minioluteus was isolated from Silybum marianum and produces biological active compounds [ 64 ]; and Aspergillus sp. and Penicillium sp.…”

Talaromyolides A–D and Talaromytin: Polycyclic Meroterpenoids from the Fungus Talaromyces sp. CX11

“…Meroterpenoids are hybrid natural products partially derived from the polyketide and partially from the terpenoid pathway. , Recently, meroterpenoids have attracted attention because of their chemical diversity and biological activities. , The genus Talaromyces is known to produce meroterpenoids, polyketides, and furanosteroids with novel chemical structures. , The meroterpenoid class isolated from this genus usually possesses congested polycyclic skeletons, such as berkeleyacetals with 6/7/6/5/6 cyclic system and 6/6/6/6 cyclic talarolutins . Over the past few decades, only 15 meroterpenoids constructed with drimane-type sesquiterpene moieties and C10 polyketide units have been reported. − In this study, a chemical investigation on the strain CX11 resulted in the isolation of five new meroterpenoids.…”

“…5,6 The meroterpenoid class isolated from this genus usually possesses congested polycyclic skeletons, such as berkeleyacetals with 6/7/6/5/6 cyclic system 6 and 6/6/6/6 cyclic talarolutins. 7 Over the past few decades, only 15 meroterpenoids constructed with drimane-type sesquiterpene moieties and C10 polyketide units have been reported. 8−11 In this study, a chemical investigation on the strain CX11 resulted in the isolation of five new meroterpenoids.…”

Asperversins A and B, Two Novel Meroterpenoids with an Unusual 5/6/6/6 Ring from the Marine-Derived Fungus Aspergillus versicolor

“…Therefore, a plausible biosynthetic pathway is proposed to illustrate the generation of 1 and 2 ( Scheme 1 ). Asperversins A ( 1 ) and B ( 2 ) are probably biosynthesized via a polyketide and mevalonate hybrid biogenetic pathway [ 2 , 21 , 22 ]. After a series of oxidations, the A ring of I was opened, and then, followed by the key electrophilic addition of OH-4 with the α , β- unsaturated carboxylic acid bond, the intermediate III , featuring a tetrahydrofuran ring, was derived from II .…”