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− Seven previously undescribed ent -eudesmane sesquiterpenoids (1 – 7), as well as seven known analogs (8 – 14), were isolated from the Chinese liverwort Chiloscyphus polyanthus var. rivularis. Their structures were established based on comprehensive spectroscopy analysis, electronic circular dichroism calculations, as well as biosynthetic considerations. The cytotoxicity against HepG2 (Human hepatocellular carcinomas) cancer cell line, and antifungal activity against Candida albicans SC5314 of all isolated ent -eudesmane sesquiterpenoids were preliminarily tested, results showed that the tested compounds did not display obvious cytotoxicity and antifungal activities under the tested concentration. Seven undescribed ent -eudesmanes were isolated and identified from C. polyanthus. Structures were determined by extensive spectroscopic analyses. The cytotoxicity and antifungal activity of all compounds were preliminarily tested. [Display omitted] • Seven undescribed ent -eudesmanes were isolated and identified from C. polyanthus. • Structures were determined by extensive spectroscopic analyses. • The cytotoxicity and antifungal activity of all compounds were preliminarily tested. [ABSTRACT FROM AUTHOR]

Eight undescribed terpenoids, namely, odongrossins A−H, together with two known terpenoids were isolated from Odontoschisma grosseverrucosum Stephani (Cephaloziaceae). Their structures were established based on NMR data, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction measurements. Odongrossin A and odongrossin G displayed moderate anti-virulence activities against CDR1 -and CDR2 -efflux-pump-deficient Candida albicans DSY654. Further investigation of odongrossin A revealed that it inhibited adhesion and biofilm formation on C. albicans DSY654. The results regarding the transcription levels of genes demonstrated that odongrossin A could regulate the expression of genes that are associated with the virulence of C. albicans DSY654. Eight undescribed terpenoids were isolated from O. grosseverrucosum. Odongrossin A displayed antifungal virulence activity. Image 1 • Eight undescribed terpenoids were isolated from O. grosseverrucosum. • Structures were determined by extensive spectroscopic analyses. • Odongrossin A displayed antifungal virulence activity. [ABSTRACT FROM AUTHOR]

An enantioselective synthetic approach for preparing manginoids and guignardones, two types of biogenetically related meroterpenoids, is reported. This bioinspired and divergent synthesis employs an oxidative 1,3‐dicarbonyl radical‐initiated cyclization and cyclodehydration of the common precursor to forge the central ring of the manginoids and guignardones, respectively, at a late stage. Key synthetic steps include silica‐gel‐promoted semipinacol rearrangement to form the 6‐oxabicyclo[3.2.1]octane skeleton and the Suzuki–Miyaura reaction of vinyl bromide to achieve fragment coupling. This synthesis protocol enables the asymmetric syntheses of four fungal meroterpenoids from commercially available materials. [ABSTRACT FROM AUTHOR]

An enantioselective synthetic approach for preparing manginoids and guignardones, two types of biogenetically related meroterpenoids, is reported. This bioinspired and divergent synthesis employs an oxidative 1,3‐dicarbonyl radical‐initiated cyclization and cyclodehydration of the common precursor to forge the central ring of the manginoids and guignardones, respectively, at a late stage. Key synthetic steps include silica‐gel‐promoted semipinacol rearrangement to form the 6‐oxabicyclo[3.2.1]octane skeleton and the Suzuki–Miyaura reaction of vinyl bromide to achieve fragment coupling. This synthesis protocol enables the asymmetric syntheses of four fungal meroterpenoids from commercially available materials. [ABSTRACT FROM AUTHOR]

A divergent synthetic approach to biogenetically related diterpenoids such as ent‐kauranes, ent‐trachylobanes, ent‐beyerane, and ent‐atisane has been developed. The unified synthetic route involves the De Mayo reaction to rapidly generate the bicyclo[3.2.1]‐octane moiety of ent‐kaurane. The key reactions also include bioinspired nucleophilic cyclopropanation generating the [3.2.1.02,7]‐tricyclic core of ent‐trachylobane and regioselective cyclopropane fragmentation furnishing ent‐beyerane and ent‐atisane through the nucleophilic attack and protonation of the cyclopropane ring. This strategy enables the asymmetric total syntheses of six diterpenoids from the commercially available geraniol. [ABSTRACT FROM AUTHOR]

A divergent synthetic approach to biogenetically related diterpenoids such as ent‐kauranes, ent‐trachylobanes, ent‐beyerane, and ent‐atisane has been developed. The unified synthetic route involves the De Mayo reaction to rapidly generate the bicyclo[3.2.1]‐octane moiety of ent‐kaurane. The key reactions also include bioinspired nucleophilic cyclopropanation generating the [3.2.1.02,7]‐tricyclic core of ent‐trachylobane and regioselective cyclopropane fragmentation furnishing ent‐beyerane and ent‐atisane through the nucleophilic attack and protonation of the cyclopropane ring. This strategy enables the asymmetric total syntheses of six diterpenoids from the commercially available geraniol. [ABSTRACT FROM AUTHOR]

Three unprecedented ent -labdane and pallavicinin based dimers pallamins A–C formed via [4 + 2] Diels-Alder cycloaddition, together with eight biosynthetically related monomers were isolated from Pallavicinia ambigua. Their structures were determined by the extensive analysis of HRESIMS and NMR spectra. The absolute configurations of the labdane dimers were determined by single crystal X-ray diffraction of the homologous labdane units, and 13C NMR and ECD calculations. Moreover, a preliminary evaluation of the anti-inflammatory activities of the isolated compounds was performed using the zebrafish model. Three of the monomers demonstrated significant anti-inflammatory activity. Three unprecedented ent -labdane and pallavicinin based dimers pallamins A–C, formed via a [4 + 2] Diels-Alder cycloaddition, were isolated from Pallavicinia ambigua. Their structures were elucidated by extensive analysis of HRESIMS and NMR spectra and theoretical calculations. [Display omitted] • Three labdane dimers and eight labdanes were isolated from Pallavicinia ambigua. • Dimers were formed via [4 + 2] Diels-Alder cycloaddition between two labdane units. • The absolute configurations were determined by X-ray analysis and ECD calculations. • Three labdanes displayed anti-inflammatory activity based on the zebrafish model. [ABSTRACT FROM AUTHOR]