A substrate for solid phase synthesis comprising a solid phase-linker combination of the formula I is disclosed. Also disclosed are processes for preparing the substrate and chemical intermediates useful therein. Among the novel intermediates are compounds of the formula II wherein R1 is —NO2 or —CHO; R2 is —OCH3, —CHO or —H; R3 is chosen from the group consisting of hydroxyl, the residue of a solid support having a plurality of amino groups, and the residue of an ester, and n=1 or 3. A substrate of solid phase synthesis of the formula III is also disclosed.