1: 2,6-Dichloro-9H-purine With (3,4-dihydro-2H-pyran-2-yl)methoxy-linked Merrifield resin; camphor-10-sulfonic acid in 1,2-dichloro-ethane T=60°C; 30 h; 2: 1-phenyl-piperazine With triethylamine in butan-1-ol T=80°C; 3 h; 3: With trifluoroacetic acid in dichloromethane T=20°C; 0.166667 h;