Protection and Deprotection Specific to Peptide Synthesis

Peptide synthesis becomes further complicated by the presence of functional groups in the side chains, other than hydroxyl and amino groups that need to be selectively protected. 

Trifluoromethane sulfonic acid with thioanisole Photolysis 

Notes 1. Acylation/deaoylation is commonly used for purification/analysis/preparation of glycoses and glycans. Acyl groups used are  

Various benzyl derivatives are used to protect polyhydroxy groups of glycoses and their removal conditions (in parentheses) are where R = H (Pd), OCH3 (TFA), OCOCH3 (NaOCCHg), Cl/Br (Pd, secondary amine). 

A number of tertiary silyl derivatives, besides TMS, such as terT-butyldimethylsilyl (TBDMS), and terr-butyidiphenylsilyl (TBDPS) have been used as protecting polyhydroxyl groups in glycan synthesis  

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