Isopimaric acid from

Isopimaranes occur in some pine (Pinaceae) and juniper species (Cupressaceae). Examples include 7,15-isopimaradiene and 8,15-isopimaradien-18-oic acid (A -isopimaric acid) from Pinus silvestris as well as 8(14),15-isopimaradiene-3,18-diol and 8,15-isopimaradiene-3,7,19-triol from Juniperus thurifera. 

Smith E, Williamson E, Zloh M, Gibbons S (2005) Isopimaric acid from Pinus nigra shows activity against multidrug-resistant and EMRSA strains of Staphylococcus aureus. Phytother Res 19(6) 538-542. doi 10.1002/ptr.l711... 

A number of diterpenes are known to be active against herbivores ( ). The diterpenes abietic, dehydroabietic, 12-methoxy-abietic, sandaracopimaric, and isopimaric acid serve as feeding deterrents for the larch sawfly, Pristiphora erichsonii in single needles from new shoots of tamarack (Larix laricina) (133). The larvae of this insect do eat tufted needles on short shoots of the same trees. 

Pimaric acid (6) and isopimaric acid (7) differ in carbon skeleton from abietic acid, and the amounts initially present in rosin are lost in the process described for the preparation of dehydroabietic acid. In the step of dehydrogenation with palladium the two acids act as hydrogen acceptors and are converted into a mixture of dihydro-pimaric and dihydroisopimaric acids. Note that pimaric acid and isopimaric acid have been shown to be rearranged to abietic acid by concentrated sulfuric acid. 

Totarol, 3-oxototarol, A -3-oxototarol, 1,3-dioxototarol, xanthoperol, sugiol, sandaracopimaric acid, and isopimaric acid have been isolated from Juniperus conferta ... 

Six pimarane diterpenes (297-302) were obtained from the rhizomes of an imnamed Kaempferia (Thai name jang-ngung) [270]. Rhizomes of K. pulchra were found to contain two pimarane diterpenes (303,304) [271], which were reported to possess anti-inflammatory action [272]. Isopimaric acid, a well-known pimarane derivative, was also isolated from the chloroform extract of the rhizomes oiKaempferia sp.[256]. 

Levopimaric acid and isopimaric acid are very important adjuvants for cellulose pulp production and the paper industry [168]. Another relevant aspect of isopimaric acid, extracted from immature cones of P. nigra, is that it showed activity against a multidrug-resistant bacteria strain of S. aureus [139]. 

Johnston, J. P., and K. H. Overton The Pimarane Cassane Rearrangement. Synthesis of a Potential Intermediate from Isopimaric Acid. J. Chem. Soc. Perkin I 1973, 853. 

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