Analogy by ring opening open-chain analogs

Analogy by ring opening open-chain analogs 

Open ring analogs of cyclic active principles (open drugs, open-chain analogs) can be designed and synthesized. The usefulness of such compounds is rather questionable, and 

The open analog is again cyclized after oxidation or dehydration by a metabolic enzyme. We deal here with potential rings, which represent nothing more than metabolic precursors of the active species. 

The open analog does not cychze in vivo but can present some conformational analogy with the ring-containing active principle. These kinds of analogs are known as pseudocycles. 

Potential rings in vivo return to the cyclic derivative 

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A. Analogy by ring opening open-chain analogs... 

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