Gancochlearols E - I, meroterpenoids from Ganoderma cochlear against COX-2 and triple negative breast cancer cells and the absolute configuration assignment of ganomycin K

Insights into Ganoderma fungi meroterpenoids opening a new era of racemic natural products in mushrooms

Ganoderma meroterpenoids (GMs) containing 688 structures to date were discovered to have multiple remarkable biological activities. 65.6% of meroterpenoids featuring stereogenic centers from Ganoderma species are racemates. Further, GMs from different Ganoderma species seem to have their own characteristics. In this review, a comprehensive summarization of GMs since 2000 is presented, including GM structures, structure corrections, biological activities, physicochemical properties, total synthesis, and proposed biosynthetic pathways. Additionally, we especially discuss the racemic nature, species-related structural distribution, and structure-activity relationship of GMs, which will provide a likely in-house database and shed light on future studies on GMs.

Natural sesquiterpene quinone/quinols: chemistry, biological activity, and synthesis

Covering: 2010 to 2021Sesquiterpene quinone/quinols (SQs) are characterized by a C15-sesquiterpenoid unit incorporating a C6-benzoquinone/quinol moiety. Numerous unprecedented carbon skeletons have been constructed with various connection patterns between the two parts. The potent anti-cancer, anti-inflammatory, anti-microbial, anti-viral, and fibrinolytic activities of SQs are associated with their diverse structures. The representative avarol has even entered the stage of clinical phase II research as an anti-HIV agent, and was developed as paramedic medicine against psoriasis. This review provides an overall summary of 558 new natural SQs discovered between 2010 and 2021, including seven groups and sixteen structure-type subgroups, which comprehensively recapitulates their chemical structures, spectral characteristics, source organisms, biological activities, synthesis, and biosynthesis, aiming to expand the application scope of this unique natural product resource.

COX-2 and iNOS inhibitory epimeric meroterpenoids from Ganoderma cochlear and structure revision of cochlearol Q

Four novel epimeric meroterpenoids, ganadone A (1), 3',10'-di-epi-ganadone A (2), 10'-epi-ganadone A (3), and 3'-epi-ganadone A (4) as well as another pairs of epimers, ganadone B (5) and 10'-epi-ganadone B (6), with a same basic skeleton compound ganadone C (7), together with two lactonized meroterpenoids, ganadones D and E (8 and 9) were isolated from the fruiting bodies of Ganoderma cochlear. Compounds 1-7 were constructed with fascinating adjacent 6',7'-bifuran ring system. Fortunately, we have revised our previously reported structure cochlearol Q, which was proposed pyrano[6',7'-b]pyran ring system into 6',7'-bifuran motif. All the isolates were characterized by analysis of HRESIMS, NMR spectroscopy and 1 was supported by X-ray crystallography analysis. The absolute stereochemistry of 1-9 were assigned by quantum chemical calculations. Biological evaluation of 1-9 showed that 5, 6, and 9 have significant anti-inflammatory potentials.

Meroterpenoids with a large conjugated system from Ganoderma lucidum and their inhibitory activities against renal fibrosis

Baoslingzhines A-E (1-5), five new meroterpenoids were isolated from the fruiting bodies of Ganoderma lucidum. The structures including their absolute configurations were characterized by using spectroscopic and computational methods. Compound 1 is a novel trinormeroterpenoid featuring the presence of an unusual dihydronaphthalene representing an unprecedented meroterpenoid skeleton. Compounds 2-4 are mononormeroterpenoids characteristic of a large conjugated system. Among them, racemic 3 and 4 were separated by HPLC on chiral phase. Biological evaluation toward kidney fibrosis found that compounds 2 and (+)-3 could inhibit the expression of fibronectin and collagen I dose dependently in TGF-β1-induced rat kidney proximal tubular cells (NRK-52e). Additionally, (+)-3 could also down regulate ɑ-SMA in a concentration dependent manner. Further investigation showed that 2 could inhibit Smad2 phosphorylation.

Structural Optimization and Improving Antitumor Potential of Moreollic Acid from Gamboge

Moreollic acid, a caged-tetraprenylated xanthone from Gamboge, has been indicated as a potent antitumor molecule. In the present study, a series of moreollic acid derivatives with novel structures were designed and synthesized, and their antitumor activities were determined in multifarious cell lines. The preliminary screening results showed that all synthesized compounds selectively inhibited human colon cancer cell proliferation. TH12-10, with an IC50 of 0.83, 1.10, and 0.79 μM against HCT116, DLD1, and SW620, respectively, was selected for further antitumor mechanism studies. Results revealed that TH12-10 effectively inhibited cell proliferation by blocking cell-cycle progression from G1 to S. Besides, the apparent structure-activity relationships of target compounds were discussed. To summarize, a series of moreollic acid derivatives were discovered to possess satisfactory antitumor potentials. Among them, TH12-10 displays the highest antitumor activities against human colon cancer cells, in which the IC50 values in DLD1 and SW620 are lower than that of 5-fluorouracil.