we are in a strong position to supply:

4-bromoindole;

indole-4-nitrylethylene;

2-chloroadenene;

 2-fluoroadenine;

2,6-Dichloropurine;

 6-chloro-2-fluoropurine;

2,6-Diaminopurine;

6-Chloro-2-Fluoropurine;

 6-Mercaptopurine,

2-amino-6-CHloropurine;

2-bromopyrimidine;

2-aminopyrimidine;

 2-hydroxypyrimidine;

 2-cyanopyrimidine.