Pepluane and Paraliane Diterpenoids from Euphorbia peplus with Potential Anti-inflammatory Activity

Abstract

Twelve new diterpenoids based on two rare skeletal types, namely, paralianones A-D (1-4) and pepluanols A-H (5-12), along with five known compounds, were isolated from an acetone extract of Euphorbia peplus. Their structures were proposed based on 1D and 2D NMR spectroscopic data analysis. These diterpenoids were evaluated for potential anti-inflammatory activity in a lipopolysaccharide-stimulated mouse macrophage cellular model. Compounds 3, 4, 11, 13, and 16 displayed moderate inhibitory effects on NO inhibition, with IC50 values ranging from 29.9 to 38.3 μM.

Jatrophane and rearranged jatrophane-type diterpenes: biogenesis, structure, isolation, biological activity and SARs (1984–2019)

“…Compounds 68, 69, 62, 72, and 61 displayed inhibitory effects on NO inhibition, with IC 50 values of 33.7, 38.3, 36.6, 29.9, and 37.1 lM, respectively. In addition, none of the test compounds displayed any obvious cytotoxicity to RAW264.7 cells (Wan et al 2016a). Chen et al (2014) isolated new compounds 239-241, and 330 along with five known analogues: 332, 247, 337, 245, and 256 from E. helioscopia.…”

“…The segetane diterpenoids are the main constituents of Euphorbia segetalis (Jakupovic et al 1998a), a species that the name of the entire skeletal class had originated from it. Segetanes had been isolated from E. peplus (Wan et al 2016a) and E. portlandica (Madureira et al 2006) and E. paralias grown in Turkey (Ö ksüz et al 1997), Spain (Jakupovic et al 1998c), Egypt (Abdelgaleil et al 2001), and Italy . They are characterized by a modified jatrophane skeleton comprising a bicyclo [4.3.1] undecane ring system which could have up to nine chiral centers.…”

Euphorbia Diterpenes: An Update of Isolation, Structure, Pharmacological Activities and Structure–Activity Relationship

“…Examples of modified jatrophane diterpenes isolated from Euphorbia species were mysrinanes from E. prolifera ( 316 – 322 ) [ 37 ], paralianones from E. peplus ( 323 – 325 ) [ 38 ], pimaranes from E. stracheyi ( 326 – 328 ) [ 32 ], and premyrsinanes from E. sanctae-catharinae ( 329 – 331 ) [ 26 ]. Others were myrsinol from root extracts of E. prolifera ( 347 – 350 ) [ 74 ] and from the aerial extracts of E. dracunculoides ( 351 – 352 ) [ 58 ], paralianes from E. esula ( 353 ) [ 49 ] and E. peplus ( 354 – 361 ) [ 72 ] and pepluane ( 362 – 365 ) [ 72 ]. Jatrophane diterpenes can be polyacrylate derivatives, with the number of ester groups varying from three, as in guyonianin E, to eight, as in esulatin H. The acyl groups common to jatrophane diterpenes include benzoyl, acetyl, isobutanoyl, or nicotinoyl 2-methylbutanoyl, and propionyl, butanoyl, tigloyl, angeloyl, or cinnamoyl.…”

Cascade One‐Pot Synthesis of Indanone‐Fused Cyclopentanes from the Reaction of Donor‐Acceptor Cyclopropanes and Enynals via a Sequential Hydrolysis/Knoevenagel Condensation/[3+2] Cycloaddition

“…Among different types of all‐carbon polycyclic skeletons, the tricyclic [6,5,5]‐fused system is a unique framework, and it is the core of many important natural products, such as pallidol . theacitrinin C (Figure ), dihydromaltophilin, and paralianone C . Therefore, efficient synthesis methods for the all‐carbon tricyclic [6,5,5]‐fused system should be of great importance…”