Expedient solid-phase synthesis of fluorogenic protease substrates using the 7-amino-4-carbamoylmethylcoumarin (ACC) fluorophore

A highly efficient solid-phase synthesis method for the preparation of fluorogenic protease substrates based upon the bifunctional leaving group 7-amino-4-carbamoylmethylcoumarin (ACC) is reported. Methods for the large-scale preparation of the novel fluorogenic leaving-group ACC are provided (Scheme 1). Detailed procedures are also provided for loading a diverse set of amino acids to support-bound ACC in good yields and with minimal racemization. Finally, procedures are included for the preparative synthesis of optimized ACC substrates for HIV-1 protease and plasmin.