Dammarane-type triterpenoids as 11β-HSD1 inhibitors from Homonoia riparia

Triterpenoids with multi-skeletons as 11 β -HSD1 inhibitors from Euphorbia sikkimensis

An exploration for 11β-HSD1 inhibitors from the whole plant of Euphorbia sikkimensis led to the identification of 10 undescribed triterpenoids 1-10, as well as 7 known triterpenoids (11-17). Their structures were determined by a combination of spectrum elucidations, conformational analyses and quantum chemical calculations. (23E)-25-methoxy-eupha-14,23-diene-3β,7α-diol (1) and (23E)-3β-dihydroxy-27-noreupha-7,23-diene-25-one (2) are two rare cases that feature a rearrangement of Me-30 (14 → 8) and a degradation of Me-27, respectively, in the euphane-type triterpenoid family. It is an interesting phenomenon that (23E)-3β-hydroxy-25-methoxy-eupha-8,23-diene-7-one (4) and (23E)-3β-hydroxy-25-methoxy-lanost-8,23-diene-7-one (5) coexist in the same plant, sharing the same planar structure but belonging to different structural types of triterpenoids. Compounds 3-5 and 14 show significant inhibitory activity against 11β-HSD1 with IC₅₀ values of 6.50 ± 0.22, 1.31 ± 0.34, 9.38 ± 0.64, and 8.27 ± 0.33 μM, respectively. The structure-activity relationship study shows that the euphane-type triterpenoids exhibit the best inhibitory activity, which is in accord with the fact of the euphane-type triterpenoids having the best ability to bind to the active pocket of 11β-HSD1 in the molecular docking experiments.

Two new dammarane-type triterpenoids from the green walnut husks of Juglans mandshurica Maxim

Two new dammarane-type triterpenoids, dammar-3α,12(R),20(S)-triol-12,32(R);20,32-diepoxy-25-methy-25-en-tridecacyclic ether (1) and (23E)-12β,20(R),25(S),26-tetrahydroxydammar-23-en-3-one (2) were isolated from the green walnut husks of Juglans mandshurica Maxim together with six known compounds. Their structures were elucidated through extensive spectroscopic analyses and by comparison with the literature, and the cytotoxic activities of these compounds were evaluated.

Paeonone A, a novel nonanortriterpenoid from the roots of Paeonia lactiflora

Paeonone A (1), a unique nonanortriterpenoid, and a new octanortriterpenoid, paeonone B (2), were isolated from the roots of Paeonia lactiflora, together with a known analogue, palbinone (3). Paeonone A (1) is the first example of naturally occurring nonanortriterpenoid with a diketo acid group. Extensive NMR and HRESIMS experiments were applied to identify the structures of 1 and 2, and their absolute configurations were solved by single-crystal X-ray diffraction and ECD data. Biological properties of 1-3 were explored against pancreatic lipase and cancer cell lines.

Triterpenoids

Covering 2014. Previous review: Nat. Prod. Rep., 2017, 34, 90-122 This review covers the isolation and structure determination of triterpenoids reported during 2014 including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes, isomalabaricanes and saponins; 374 references are cited.

Cytotoxic dammarane-type triterpenoids from the leaves of Viburnum sambucinum

Four new dammarane-type triterpenoids (1-4) and twelve known compounds (5-16) were isolated from the leaves of Viburnum sambucinum Reinw. ex Blume. Their structures were determined by spectral data analysis, including MS and 2D NMR. Cytotoxic activity evaluation in vitro against four cancer cell lines (KB, LU-1, HepG2 and MCF7) suggested that the octanor-dammarane derivatives were the main cytotoxic components of the leaves of V. sambucinum.

Plant Resources, (13)C-NMR Spectral Characteristic and Pharmacological Activities of Dammarane-Type Triterpenoids

Dammarane-type triterpenoids (DTT) widely distribute in various medicinal plants. They have generated a great amount of interest in the field of new drug research and development. Generally, DTT are the main bioactive ingredients abundant in Araliaceae plants, such as Panax ginseng, P. japonicas, P. notoginseng, and P. quinquefolium. Aside from Araliaceae, DTT also distribute in other families, including Betulaceae, Cucurbitaceae, Meliaceae, Rhamnaceae, and Scrophulariaceae. Until now, about 136 species belonging to 46 families have been reported to contain DTT. In this article, the genus classifications of plant sources of the botanicals that contain DTT are reviewed, with particular focus on the NMR spectral features and pharmacological activities based on literature reports, which may be benefit for the development of new drugs or food additives.

Synthesis of hupehenols A, B, and E from protopanaxadiol

A unified semisynthesis approach from protopanaxadiol to hupehenols A, B, and E was described. The synthesis provided the primary SAR and the possibility of further medicinal development of hupehenols.

Hupehenols A-E, selective 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitors from Viburnum hupehense

Five selective 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) competitive inhibitors, hupehenols A-E (1-5), were isolated from Viburnum hupehense. The structure elucidation indicated that compounds 1-5 are new 20,21,22,23,24,25,26,27-octanordammarane triterpenoids. Their structures were established on the basis of NMR spectroscopic and mass spectrometric analysis. Hupehenols A-E (1-5) showed inhibition against human 11β-HSD1, with hupehenols B (2) and E (5) having IC50 values of 15.3 and 34.0 nM, respectively. Moreover, hupehenols C (3) and D (4) are highly selective inhibitors of human 11β-HSD1 when compared to murine 11β-HSD1.

Ricinodols A–G: new tetracyclic triterpenoids as 11β-HSD1 inhibitors from Ricinodendron heudelotii

Chemical investigation of Ricinodendron heudelotii has returned seven new tetracyclic triterpenoids with moderate to significant inhibitory effect against 11β-HSD1 enzyme.