Isopimaric acid
From Wikipedia, the free encyclopedia
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| Names | |
|---|---|
| IUPAC name
(13S)-Pimara-7,15-dien-18-oic acid | |
| Systematic IUPAC name
(1R,4aR,4bS,7S,10aR)-7-Ethenyl-1,4a,7-trimethyl-1,2,3,4,4a,4b,5,6,7,8,10,10a-dodecahydrophenanthrene-1-carboxylic acid | |
| Identifiers | |
3D model (JSmol) |
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| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.163.144 |
| KEGG | |
PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| C20H30O2 | |
| Molar mass | 302.458 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Isopimaric acid (IPA) is a toxin which acts as a large conductance Ca2+-activated K+ channel (BK channel) opener.
IPA originates from many sorts of trees, especially conifers.[1]
Chemistry
IPA is one of the members of the resin acid group and it is a tricyclic diterpene.[1]
Target
IPA acts on the large-conductance calcium activated K+ channels (BK channels).[2][3]
Mode of action
BK channels are formed by α subunits and accessory β subunits arranged in tetramers. The α subunit forms the ion conduction pore and the β subunit contributes to channel gating. IPA interaction with the BK channel enhances Ca2+ and / or voltage sensitivity of the α subunit of BK channels without affecting the channel conductance. In this state BK channels can still be inhibited by one of their inhibitors, like charybdotoxin (CTX).[2][3] Opening of the BK channel leads to an increased K+-efflux which hyperpolarizes the resting membrane potential, reducing the excitability of the cell in which the BK-channel is expressed.
