4-Methyltrityl (Mtt): a new protecting group for the side chain protection of Asn and Gln in solid-phase peptide synthesis.

The trityl group was recently introduced for the protection of the side chain carboxamide function of asparagine and glutamine. The 4-methyltrityl (Mtt) group, a structural modification of trityl, is presented here and allows more rapid cleavage from the protected peptides. Procedures for the introduction of the group and comparative cleavage reactions are also presented.