Permanent protecting group

P = Temporary protecting group R = Permanent protecting group... 

Another critical consideration was the development of an effective protecting-group strategy. We chose to employ benzyl ethers as permanent protecting groups, not to be removed during the course of intermittent deprotection events, because of their stability under moderately acidic and... 

Synthesize peptides with the base-labile Fmoc group to temporarily protect the a-amino group and acid-labile permanent side-chain protecting groups tert-butyl... 

In carbohydrate chemistry, benzyl ethers are often applied as permanent protecting groups. They are robust and are stable to a wide range of basic and acidic conditions. They can also withstand hydride reducing agents... 

P = temporary protecting group p = permanent protecting group LG = leaving group... 

Below is a list of the most commonly used hydroxyl protecting groups including conditions for their introduction and removal. For a discussion of their regioselective introduction, see Section 3.3. A rough distinction between permanent and temporary protecting groups is also made. 

Acetates and benzoates are excellent protecting groups. They can be introduced and removed in high yields in large numbers under mild conditions. Drawbacks as permanent protecting groups include their relatively limited base stability and their tendency to migrate. 

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