1: alpha-naphthyl isothiocyanate With 4-(N,N-dimethlyamino)pyridine; Merrifield resin-NH-CO-CH2-CH(SiMe2Ph)-CH2-OH; triethylamine in chloroform Heating; 2: With tetrabutyl ammonium fluoride in dichloromethane 3: acetic anhydride With pyridine in dichloromethane