A labdane diterpene and its glycoside from melodinus monogynus

Diterpenoids from Turraeanthus mannii

“…The 1 H-NMR spectrum of 3 ( Table 1) exhibited signals of three methyl groups, one methylene and one methine proton linked to an a,b-unsaturated-g-lactone, a pair of olefinic protons (d H = 4.68 and 4.90), and one oxymethine proton at d H 4.70. These 1 H NMR data were again characteristic for a labdane diterpene skeleton [8], [9], [10]. The overlapping proton signals in the range of d = 0.96 to 2.40 were assigned by COSY and HMBC data.…”

“…Thus, compound 1 was characterized as 15-acetoxy-12-hydroxy-16methyl labda-8(17),13E-diene. [8], [9], [10]. The IR spectrum revealed absorptions 1780 and 1724 cm -1 indicating the presence of a butenolide [9], and an ester carbonyl signal at 1750 cm ±1 .…”

“…[8], [9], [10]. The IR spectrum revealed absorptions 1780 and 1724 cm -1 indicating the presence of a butenolide [9], and an ester carbonyl signal at 1750 cm ±1 . The 1 H-NMR spectrum showed an allylic coupling between the signals at d H = 5.82 for H-14 and 4.78 for H 2 ± 16, attributed to an endocyclic a,û-unsaturated g-lactone moiety [13], [14].…”

“…The 13 C-NMR spectrum confirmed the presence of an acetyl group by a signal at d C = 21.7. The 1 H-NMR spectrum of 1 showed characteristic signals of a labda-8(17),13-diene skeleton[8],[9],[10], [d H = 5.43 (1H, J = 1.3 Hz ), 4.56 (1H) and 4.80 (1H)] attributable to a trisubstituted and an exocyclic double bond, respectively.The IR spectrum indicated absorption bands at 1739 and 3435 cm ±1 corresponding to ester carbonyl and hydroxy functions. The presence of a hydroxy group was confirmed by the 1 H-NMR spectrum, which showed a methine doublet of doublets at d…”

Labdanes of Natural Origin-Biological Activities (1981-2004)

“…The acetylated derivative also increased the tone and force of myocardial contraction and decreased the heart rate. Medinin showed no cardiac activity with either of the heart preparations [230]. The extract (chloroform-methanol 1:1) of the plant Dodonaea viscosa (Sapindaceae) resulted in the isolation of labdane-diterpenes, which elicited a The extracts of the bark from Juniperus procera (Cupressaceae) is used as potential anti-termite natural pesticide, while labdane-diterpenoids from the cones of Chamaecyparis obtusa (Cupressaceae) exhibited antifeedant activity against the pest insect Spodoptera litura [213,214].…”