4-Alkoxy-2-hydroxybenzaldehyde (AHB): A versatile aldehyde linker for solid-phase synthesis of C-terminal modified peptides and peptidomimetics

A new and versatile 4-alkoxy-2-hydroxybenzaldehyde (AHB) linker for solid-p hase syntheses is described, Acylation of the polymer-bound secondary amine obtained from reductive amination of the aldehyde in the AHB linker showed good reactivity. Following acylation of the phenolic hydroxyl group, the r esulting carboxamide resin was stable to treatment with 95% TFA, The O-acyl functional group was removed with 20% piperidine and the desired compound was cleaved from the resin by TFA treatment.