Oreganic acid

Oreganic acid (Figure 16), a tricarboxylated alkyl sulfate, was isolated from an endophytic fungus that inhabited living leaves of Berberis oregana, collected from Humboldt Co., California. Like the other compounds described above, isolation of this highly charged compound was accomplished in two steps by gel filtration followed by reverse phase HPLC [89]. The structure of the compound was established by the application of NMR and mass spectroscopy [89]. 

Oreganic acid [(E)-19-sulfooxy-2-nonadecene-1,2,3-tricarboxylic acid],... 

Using assay conditions where both substrates were used at km levels chaetomellic, actinoplanic, oreganic and zaragozic acids and alkyl citrates (for example, viridiofungins) were discovered from different microbial extracts. These compounds were potent selective inhibitors of FPTase activity and did not inhibit GGPTase or squalene synthase. All five classes of compounds were competitive with respect to FPP and were reversible inhibitors of FPTase activity. Three additional reports have appeared during the intervening period that described the isolation of CP 225917, manumycin, and RPR 113228 as FPP competitive inhibitors. These inhibitors, their in vitro activity and their corporate sources are summarized in Table 1. 

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