
TentaGel® Resins with Trityl Linker
TentaGel® resins are grafted copolymers consisting of a low crosslinked polystyrene matrix on which polyethylene glycol (PEG or POE) is grafted. The PEG spacer is attached to the matrix via an ethyl ether group which increases stability towards acid treatment and minimizes PEG-leaching. As PEG is a "chameleon type" polymer with hydrophobic and hydrophilic properties, the graft copolymer shows modified physico chemical properties which are highly dominated by the PEG moiety (and no longer by the polystyrene matrix). These graft copolymers are pressure stable and can be used in batch processes as well as under continuous flow conditions. The PEG spacer is in the range of MW 3000 Da.
This highly acid sensitive linker is useful for the immobilization of alcohols, amines and carboxylic acids. Before use, the trityl alcohol must be converted to the trityl chloride by treatment with acetyl chloride in DCM. The sensitivity towards acids is very comparable to the 2-chlorotrityl linker. Cleavage is in general achieved by using either 5 - 50% TFA in CH₂Cl₂ (containing 5% triisopropylsilane) or acetic acid.
This resin can also be used in Fmoc peptide synthesis. Carboxylic acids can be released under very mild acidic conditions by treatment with AcOH/TFE/DCM or HFIP in DCM. Completely protected peptides are generated under this conditions.
Residues which are sensitive to racemisation during esterification reactions like His and Cys can be attached to the resin without racemisation. Due to the bulkiness of the trityl group, diketopiperazine formation is suppressed which makes this linker ideal for peptides with C-terminal Pro.
Literature
L 4, L 5, L 6, L 7, L 24, L 25; see also: General Information