Partial Synthesis of Depside Derivatives

The partial synthesis of a depside derivative occasionally provides a convenient means of structure correlation but this procedure is more commonly used in depsidone chemistry than in structural elucidation of depsides. 

Similarly, correlation of the structure of the new depside 4 -0-methylnorsekikaic acid (254) isolated from Ramalina sp. with the common depside sekikaic acid (255) was achieved by permethylation of both 

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