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Euphorbia ebracteolata was a natural medicine for the treatment of tuberculosis. The present work has performed the investigation of bioactive chemical substances from the roots of E. ebracteolata . Using various chromatographic techniques, 15 compounds were obtained from the roots of E. ebracteolata . On the basis of widely spectroscopic data analyses, the isolated compounds were determined to be diterpenoids, including rosane derivatives ( 1–12 ), isopimarane ( 13 ), abietane ( 14 ), and lathyrane ( 15 ), among which compounds 1–4 , and 9 were undescribed previously. The inhibitory effects of isolated diterpenoids against Mycobacterium tuberculosis were evaluated using an Alamar blue cell viability assay. And two rosane-type diterpenoids 3 and 8 displayed moderate inhibitory effects on with the MIC values of 18 μg/mL and 25 μg/mL, respectively. For the potential inhibitor 3 , the inhibitory effect against the target enzyme GlmU was evaluated, which displayed a moderate inhibitory effect with the IC 50 12.5 μg/mL. Therefore, the diterpenoids from the roots of E. ebracteolata displayed anti-tuberculosis effects, which would be pay more attentions for the anti-tuberculosis agents. [ABSTRACT FROM AUTHOR]

A new rosane diterpenoid, 3a-hydroxy-5,15-rosadien-11-one (3), was isolated, together with a known rosane diterpenoid, 5,15-rosadiene-3,11-dione (4), and an aromadendrane sesquiterpenoid, ent-cyclocolorenone (5), from the Et2O extract of an unidentified Argentine liverwort Anastrophyllum species. Moreover, four known sesquiterpene lactones 6–9 and two known bibenzyls 10, 11 were isolated from the Et2O extracts of Argentine Frullania brasiliensis and Radula voluta, respectively. The structures of compounds 3–11 were determined by the use of NMR techniques.

Several novel bioactive components isolated from Chinese medicinal plants will be presented. These include novel maytansinoid tumor, inhibitors, some new ent-kaurane and rosane diterpenoids from Mallotus anomalus Meer et Chun (Euphorbiaceae), as well asnovel insecticide, stemona alkaloids from Stemona parviflora C. H. Wright (Stemonaceae). Both are native plants of Hainan island, Chine. 2D NMR techniques such as mono and hetero-COSY, NOESY, COLOC as well as H-NMR line broadening effect were utilized for structure elucidation. The separation techniques, struture elucidations and bioassay results will be reported.

Two new diterpeniods, euphebracteolatins A and B ( 1 and 2, resp.) were isolated from Euphorbia ebracteolata Hayata, along with two known ones (3 R)- ent-rosa-1(10),15-dien-3 α-ol ( 3) and yuexiandajisu D ( 4). The structures were established by extensive spectroscopic analyses and comparison with literature data. [ABSTRACT FROM AUTHOR]

A new rosane diterpenoid, 3α-hydroxy-5,15-rosadien-11-one (3), was isolated, together with a known rosane diterpenoid, 5,15-rosadiene-3,11-dione (4), and an aromadendrane sesquiterpenoid, ent-cyclocolorenone (5), from the Et2O extract of an unidentified Argentine liverwort Anastrophyllum species. Moreover, four known sesquiterpene lactones 6-9 and two known bibenzyls 10, 11 were isolated from the Et2O extracts of Argentine Frullania brasiliensis and Radula voluta, respectively. The structures of compounds 3-11 were determined by the use of NMR techniques. [ABSTRACT FROM AUTHOR]

Four undescribed regular rosane-type diterpenoids euphominoids M−P and three undescribed rearranged rosane-type diterpenoids euphomilones C-E were isolated from the whole plants of Euphorbia milii Des Moul., along with nine known compounds. Their structures were elucidated by detailed interpretation of the NMR and mass spectroscopy. The absolute configurations were established by single-crystal X-ray diffraction experiments, as well as comparative analyses of calculated and experimental ECD spectra. Euphominoid M featured a highly oxygenated ring A and a rare four-membered oxygen ring while euphomilones C-E possessed 7/5/6 or 5/7/6 fused ring systems, which were rarely occurring in rosane-type diterpenoids. In the in-vitro bioassays, 19-norrosa-1,3,5(10),15-tetraene-2,3-diol and antiquorin showed more potent α -glucosidase inhibitory activity than the positive control acarbose while euphominoid C exhibited significant inhibitory activity against both α -glucosidase and β -glucuronidase. To the best of our knowledge, it was the first time that rosane-type diterpenoids were reported as β -glucuronidase inhibitors. [Display omitted] • Seven underscribed rosane-type diterpenoids were isolated from Euphorbia milii. • Euphominoid M featured a highly oxygenated six-membered ring. • Euphomilones C−E possessed rare 7/5/6 or 5/7/6 fused ring systems. • 19-Norrosa-1,3,5(10),15-tetraene-2,3-diol, euphominoid C and antiquorin showed obvious α -glucosidase inhibitory activity. • Euphominoid C was the first rosane-type diterpenoid with β -glucuronidase inhibitory activity. [ABSTRACT FROM AUTHOR]

Abstract: Extraction of Petalostigma pubescens heartwood followed by chromatographic purifications and crystallizations afforded five tricyclic diterpenes: 5,9-syn-rosanes petalostigmones A and B (1 and 2), the erythroxylane petalostigmone C (3), the norditerpene lactone pubescenone (4), and the known ent-cleistanthane diterpene (−)-sonderianol (5). The structures and relative stereochemistry were elucidated by means of spectroscopic methods, chemical correlations, and, in the cases of 1 and 4, by X-ray crystallographic analyses. The new isolates 1–4 are assumed to belong to the same absolute configurational family (9αCH3) of ent-pimarane-derived diterpenes as the known co-occurring (−)-5 (10αCH3). Biogenetic schemes originating from a common ent-copalyl diphosphate intermediate are presented to rationalize the structures of these natural products. A novel ring contraction–ring expansion mechanism is suggested to account for the 7-membered B ring of pubescenone. Compounds 1–5 were evaluated for their cytotoxicity; sonderianol (5) showed the highest activity against mouse leukemia cell lines L1210, P388 and mouse liver cancer cells HEPA1c1c7. [Copyright &y& Elsevier]

Two new herbertane sesquiterpenoids, (−)-herbertene-1,12-diol and (−)-γ-herbertenol, a new aromadendrane, 9-acetoxy-10-hydroxyaromadendrane, a new rosane diterpenoid, 5,15-rosadiene-3,11-dione and a new phytane, 2Z-phytene-1,15,20-triol, along with the known (−)-α-herbertenol have been isolated from the liverwort Tylimanthus renifolius. Several flavones and flavanones with an unsubstituted ring B were also identified. This is the first report of this class of flavonoids from the Hepaticae. All structures were elucidated by NMR spectroscopy. [Copyright &y& Elsevier]

• Five novel rosane diterpenoids were obtained from Euphorbia ebracteolata roots. • Diterpenoids 1 – 5 possessed unusual aromatic ring A in their structures. • Diterpenoid 1 displayed significant inhibitory effect on lipase (IC 50 = 1.0 μM, K i = 1.8 μM). The bioactive chemical constituents of Euphorbia ebracteolata have been investigated in the present work using various techniques. On the basis of chromatographic methods, such as silica gel, RP C-18 column chromatography, five novel rosane type diterpenoids with an aromatic A-ring (1 – 5) have been isolated from the roots of Euphorbia ebracteolata. Their structures were elucidated by widely spectroscopic data, including HRESI-MS, 1D and 2D NMR. Additionally, the inhibitory effects on lipase of these isolated diterpenoids were evaluated in vitro. Compound 1 as a new diterpenoid displayed significant inhibitory effect on lipase (IC 50 = 1.0 μM). And, the inhibitory kinetics has been studied fully, which determined a competitive inhibition model for compound 1 on the enzymatic activity of lipase (K i = 1.8 μM). [ABSTRACT FROM AUTHOR]