Trinorsesquiterpenoids from Inula racemosa

Structures, Occurrences and Biosynthesis of 11,12,13-Tri-nor-Sesquiterpenes, an Intriguing Class of Bioactive Metabolites

“…Compounds 23c [109], 23d and 23e [145] were isolated from the roots of Inula racemose (Figure 4). The latter showed antiproliferative activity against A549, HepG2 and HT1080 cell lines with IC 50 values of 3.71, 5.94 and 3.95 mg/mL, respectively [145].…”

“…The degraded eudesmane 23a was obtained from the Tibetan folk medicine Pulicaria insignis [ 144 , 145 ]. This tri- nor -sesquiterpene exhibited weak inhibitory activity against the influenza virus H1N1 neuraminidase in an in vitro assay [ 146 ].…”

“…Further modification of the compound will be needed to reduce toxicity while increasing antiviral activity [ 144 ]. The structure of 23a has been revised to structure 23e [ 145 ], and the diastereomer 23b was used as a precursor in the synthesis of cybullol (see geosmin derivative 34 ) [ 147 ].…”

“…In addition to the tri- nor -sesquiterpenes 23c – 23e , compounds 25 and 26 were also isolated from the roots of Inula racemosa ( Figure 4 ) [ 145 ]. All isolates were evaluated for their antiproliferative activities against three human cancer cell lines, using the CCK-8 cell viability assay.…”

Mosquito Larvicidal Constituents from the Ethanol Extract ofInula racemosaHook. f. Roots againstAedes albopictus

“…The characteristic components of the genus Inula are sesquiterpenes, such as eudesmanes, germacranes, guaianes, and bis-sesquiterpenes. In the previous reports, various sesquiterpenoids, triterpenoids, and lignans have been isolated and identified in the plant [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Isoalantolactone derived from I. racemosa roots exhibited repellency and insecticidal activity to rice weevil, Sitophilus oryzae and ovicidal activity against maize borer, Chilo partellus [20,21] However, a literature survey has shown that there is no report on larvicidal activity of I. racemosa roots against A. albopictus.…”