the invention provides compounds with activity against infectious diseases . the compounds of the invention may inhibit retroviral reverse transcriptases and thus inhibit the replication , of the virus . the compounds of the invention may be useful for treating human patients infected with a human retrovirus , such as human immunodeficiency virus or human t - cell leukemia virus which results in acquired immunodeficiency syndrome and / or related diseases . representative of the invention is a compound of the following formula , with the substituents defined herein :