Constituents of Leonotis leonurus Flowering Tops

Labdane Diterpenoids from Leonotis leonurus

“…Organic extracts of the flowering parts of the plant provided flavonoids and acyclic diterpene esters (El-Ansari et al, 2009; Agnihotri et al, 2009), while the leaves contained mostly labdane diterpenoids (Cragg and Little, 1962; Rivett, 1964; Kaplan and Rivett, 1968; Laonigro et al, 1979; Kruger and Rivett, 1988; McKenzie at al., 2006; Obikeze et al, 2008; Naidoo et al, 2011). Herein, the isolation and structure elucidation of eight new (1-8) and three known (9-11) labdane diterpenoids (Fig.…”

“Wild cannabis”: A review of the traditional use and phytochemistry of Leonotis leonurus

“…Previous phytochemical analysis of organic extracts of the flowers of L. leonurus reportedly provided flavonoids (El-Ansari et al, 2009) and acyclic diterpene esters (Agnihotri et al, 2009), while the leaves were found to contain mostly the labdane diterpenoids (Kaplan and Rivett, 1968;Kruger and Rivett, 1988;Ojewole, 2005;McKenzie et al, 2006;Obikeze et al, 2009;Naidoo et al, 2011) and polyphenolic compounds (Ojewole, 2005;Oyedemi and Afolayan, 2011).…”

“…Moreover, Agnihotri et al (2009) undertook an investigation of the ethanol extract of L. leonurus flowers and described the isolation, structural elucidation and biological activities of a new compound, 1,2,3-trihydroxy-3,7,11,15-tetramethylhexadecan-1-ylpalmitate (23), which is a diterpene ester (Table 3 and (22) and luteolin (21). However, repeated chromatography of an acetone extract of the same plant afforded Leonurenone C (3), 9,13:15,16-diepoxylabdane-6β,15α-diol (14), previously reported by Naidoo (2011) a year earlier, and nepetaefolin (4) ( Table 2 and figure 5) which was also found in Leonotis nepetifolia (He et al, 2012).…”

Leonurenones A–C: Labdane diterpenes from Leonotis leonurus

“…Thus the component(s) responsible for the reputed psychoactive effects are scientifically unverified at this time. Prior phytochemical investigations of various extracts of the plant have uncovered a number of labdane diterpenes, an iridoid glycoside and phenolic compounds, primarily of the flavonoid class (Agnihotri et al, 2009; El-Ansari et al, 2009; Kaplan and Rivett, 1968; Kruger and Rivett, 1988; Laonigro et al, 1979; McKenzie et al, 2006; Naidoo et al, 2011; Obikeze et al, 2008; Piozzi et al, 2007; Rivett, 1964). …”