CH3707140: Purine based compounds as toll-like receptor 9 antagonist

The invention provides novel purine based compounds of formula 1, method of preparation of purine based compounds and its composition useful for inhibiting signalling through Toll-like receptors. These compounds are useful in inhibiting immune stimulation involving toll-like receptor 9 (TLR9). These can be used in treatment of autoimmune disease and inflammation where aberrant activation of TLR9 plays role.