Description The side-chain Trt group can be selectively removed with 1% TFA in DCM containing 5% TIS, enabling the side-chain hydroxyl group to be selectively modified whilst the derivative is attached to the solid support. This is an excellent derivative for the synthesis of phosphothreonine containing peptides and peptides modified at the threonine side-chain [1]. The use of trityl protected amino acids was shown to result in purer products than when standard t-Bu protected amino acids were utilized [2].The product number for this product was previously 04-12-1141..