Euphorstranoids A and B, two highly rearranged ingenane diterpenoids from Euphorbia stracheyi: structural elucidation, chemical transformation, and lipid-lowering activity

Abstract

Euphorstranoids A (1) and B (2), two highly rearranged ingenane diterpenoids with an unusual 5/6/7/3 carbon ring system, were isolated from Euphorbia stracheyi. Their structures were determined by a combination...

Discovery of Ingenane Diterpenoids from Euphorbia hylonoma as Antiadipogenic Agents

“…Euphylonane J (10) had the molecular formula C 41 H 40 O 9 as derived from HRESIMS analysis (m/z 699.2585 [M + Na] + , calcd 699.2565). Comparison of its NMR spectroscopic data (Table 3) with those of euphoglonane B (18) revealed that one of the gem-dimethyls in 18 was replaced by a benzoyloxymethyl group in 10, 31 3) were comparable with those of 10, with the main differences being from an elimination of one of the three benzoyl groups in 10 and the upfield-shifted H-5 signal in 11 (δ H = 5.46 in 10 and 3.49 in 11), suggesting that 11 was a 5-O-debenzoylated analogue of 10. This assumption was secured by the observation of HMBC correlations (Figure S2).…”

“…Biogenetically, the assignment of the stereochemistry of 1 and 2 was in agreement with that of a common precursor, the co-isolated new ingenane (6) (Scheme S1). 26,27 (18) were readily assembled by corresponding COSY cross-peaks, which, in combination with the HMBCs from H-4, H-7, H 2 -12, and H 3 -18 to C-9, from H 2 -5 and H-8 to C-10, and from H 3 -20 to C-5, C-6, and C-7, facilitated the establishment of a 7/6 fused (B/ C) ring system. Furthermore, the HMBCs from both H 2 -16 and H 3 -17 to C-13, C-14, and C-15 constructed a cyclopentane fragment, attaching a hydroxymethyl (16-CH 2 OH) and a methyl (Me-17) group at C-15.…”

“…For example, the above-mentioned orlistat was derived from lipstatin, a fatty acid β-lactone produced by Streptomyces toxytricini . Also, several plant-derived antiobesity agents, such as vutiglabridin (a flavonoid), celastrol (a triterpenoid), and withaferin A (a steroidal lactone), are reaching clinical stage development. − In our early study, we found that polycyclic diterpenoids featuring a methylcyclopentane motif are promising in an antiadipogenic screening campaign. − Due to the abundance of this motif in Euphorbia plants, − Euphorbia hylonoma , a Chinese folk medicine used as a purgative, has attracted our interest, although its prior phytochemical studies focused on diterpenes with phytotoxic and anti-inflammatory activity. , Recently, euphylonoids A and B, two rearranged jatrophanes with antiadipogenic activity, were isolated as trace components from E. hylonoma . In our continuing pursuit of antiadipogenic diterpenes of this plant and for understanding the full landscape of such polycyclic diterpenoids in this species, we conducted a structure-oriented comprehensive isolation, which afforded 20 ingenanes including two rearranged ones ( 1 and 2 ) and a 9,10-epoxy tigliane ( 3 ) (Chart ).…”

Euphorbiaditerpenoids: isolation, structure, bioactivity, biosynthesis, and synthesis (2013–2021)

“…209 Euphorstranoids A and B ( 994 and 995 ), possessing an unusual 5/6/7/3 carbon ring system, might be derived from two consecutive 1,2-carbon shift rearrangements of euphstrachenol C ( 744 ), a co-occurring diterpenoid. 210 Euphorikanin A ( 996 ), a novel 5/6/7/3-fused tetracyclic diterpenoid lactone, was isolated from the roots of E. kansui . 211 Its biosynthetic precursor was supposed to be the co-isolated ingenane diterpenoid, 4- O -acetyl-5- O -benzoyl-3β-hydroxy-20-deoxyingenol.…”

Biscroyunoid A, an Anti-Hepatic Fibrotic 19-nor-Clerodane Diterpenoid Dimer with a C-16–C-12′ Linkage from Croton yunnanensis

“…Croton yunnanensis W. W. Smith (Euphorbiaceae) is a shrub distributed in the southwest provinces of mainland China . Previous phytochemical investigations of this plant revealed diterpenoids and sesquiterpenoids as the major metabolites, of which some showed selective cytotoxicity against three tumor cell lines, SMMC-7721, HL-60, and A549. , In our continuing efforts toward obtaining novel diterpenoids from plants in the family Euphorbiaceae, − a 19- nor -clerodane diterpenoid dimer ( 1 ) featuring a C-16–C-12′ linkage, along with its precursor ( 2 ), were isolated from C. yunnanensis . Their structures (Figure ) were elucidated by spectroscopic, computational, and single-crystal X-ray diffraction methods.…”