1: 6-aminopurine With potassium carbonate in N,N-dimethyl-formamide T=60°C; 0.5 h; 2: cyclopentyl-bromide in N,N-dimethyl-formamide T=65°C; 72 h;

ammonia; N-ethyl-N,N-diisopropylamine in ethanol Heating;

1: 6-aminopurine With potassium carbonate in N,N-dimethyl-formamide T=65°C; 0.5 h; Inert atmosphere; 2: cyclopentyl-bromide in N,N-dimethyl-formamide T=65°C; 72 h; Inert atmosphere;

T=230°C;