Furan ring structures, toxicity from

Potential toxicity arising from the furan and thiophene ring structures is a concern in designing potential drug leads, but potential leads should not be eliminated on those grounds alone. The success of current pharmaceuticals that contain furan and thiophene moieties is a clear indication that ftiran- and thiophene-containing therapies can be made safe, and even exploited as in the case of clopidogrel. 

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