16633-27-5Relevant academic research and scientific papers
Transformations of manool. tri- and tetracyclic norditerpenoids with in vitro activity against Plasmodium falciparum
Van Wyk, Albert W. W.,Lobb, Kevin A.,Caira, Mino R.,Hoppe, Heinrich C.,Davies-Coleman, Michael T.
, p. 1253 - 1258 (2007)
The known 17-norisopimar-15-ene-8β,13β-diol (5) and five new semisynthetic norditerpenoids, ethyl 17-norabiet-13-(15)-E-en-8β-ol-16-oate (6), ethyl 17-norabiet-13(15)-Z-en-8β-ol-16-oate (7), 17-norpimaran- 13α-ethoxy-8,16-olactone (8), 17-norisopimarane-8β,15-diol (9), and 17-norarabiet-13(15)-ene-8β,16-diol (10), were prepared from manool (11). Standard spectroscopic data including X-ray crystal analysis were used to determine the structures of 5-10. All five compounds exhibited in vitro antiplasmodial activity against the malarial parasite Plasmodium falciparum at varying μg mL-1 concentrations.
Synthesis and anti-plasmodial activity of 8β, 13β- Dihydroxypodocarpane derivatives
Young, Ryan M.,Popplewell, Wendy L.,Caira, Mino R.,Van Zyl, Robyn L.,Davies-Coleman, Michael T.
scheme or table, p. 18 - 23 (2011/05/04)
8β,13β-Dihydroxypodocarpane and eight C-13 substituted derivatives were prepared from the precursor 8bhydroxy-13-podocarpanone synthesised from the naturally occurring diterpene (+)-manool. The synthetic compounds exhibited a range of anti-plasmodial activities (IC50 1-29 μM) and only induced minimal haemolysis of erythrocytes at concentrations 50 and 100 μM. No changes in the morphology of erythrocytes were detected at sub-haemolytic concentrations.
Semisynthesis of labdane diterpene metabolites from the nudibranch Pleurobranchaea meckelii
van Wyk, Albert W.W.,Davies-Coleman, Michael T.
, p. 12179 - 12184 (2008/02/10)
Two isomeric labdane aldehyde metabolites (1 and 2), first isolated from the skin of the Notaspidean nudibranch Pleurobranchaea meckelii, were synthesized in six steps from manool in 19 and 6% overall isolated yields, respectively.
Bifunctional abietadiene synthase: Free diffusive transfer of the (+)-copalyl diphosphate intermediate between two distinct active sites
Peters,Ravn,Coates,Croteau
, p. 8974 - 8978 (2007/10/03)
Abietadiene synthase (AS) catalyzes two sequential, mechanistically distinct cyclizations in the conversion of geranylgeranyl diphosphate to a mixture of abietadiene double bond isomers as the initial step of resin acid biosynthesis in grand fir (Abies grandis). The first reaction converts geranylgeranyl diphosphate to the stable bicyclic intermediate (+)-copalyl diphosphate via protonation-initiated cyclization. In the second reaction, diphosphate ester ionization-initiated cyclization generates the tricyclic perhydrophenanthrene-type backbone, and is directly coupled to a 1,2-methyl migration that generates the C13 isopropyl group characteristic of the abietane family of diterpenes. Using the transition-state analogue inhibitor 14,15-dihydro-15-azageranylgeranyl diphosphate, it was demonstrated that each reaction of abietadiene synthase is carried out at a distinct active site. Mutations in two aspartate-rich motifs specifically delete one or the other activity and the location of these motifs suggests that the two active sites reside in separate domains. These mutants effectively complement each other, suggesting that the copalyl diphosphate intermediate diffuses between the two active sites in this monomeric enzyme. Free copalyl diphosphate was detected in steady-state kinetic reactions, thus conclusively demonstrating a free diffusion transfer mechanism. In addition, both mutant enzymes enhance the activity of wild-type abietadiene synthase with geranylgeranyl diphosphate as substrate. The implications of these results for the kinetic mechanism of abietadiene synthase are discussed.
SYNTHESIS OF LABDA-8(17),13(14)-DIENE-15,16-OLIDE AND 15,16-EPOXY-LABDA-8(17),13(16)-14-TRIENE AND THEIR REARRANGEMENT TO CLERODANE DERIVATIVES
Nakano, Tatsuhiko,Martin, Alfonso,Rojas, Anibal
, p. 1217 - 1219 (2007/10/02)
The title compounds 1b and 1c were synthesized from manool.On treatment with either trifluoroacetic acid or formic acid 1b provided in nearly 100percent yield 4a with a rearranged labdane skeleton.With sulfuric acid, however, 1b gave solely Δ8,9-isomer 5.Reduction of 4a with lithium diisobutylaluminium hydride afforded 4b.On treatment with sulfuric acid 4a reverted to 5.Rearrangement of the epoxide 6 with boron trifluoride-etherate led to a complex product mixture from wich no pure substance was obtained.
Stereoselective Synthesis of the Novel Marine Diterpene (+)-Isoagatholactone
Imamura, Paulo M.,Sierra, Manuel Gonzalez,Ruveda, Edmundo A.
, p. 734 - 735 (2007/10/02)
The synthesis of (+)-isoagatholactone (1) from (+)-manool (4) via the key intermediate ent-methyl isocopalate (2) is described.
