120503-30-2 6-Dimethylaminopurine-2',3'-dideoxyriboside AIDS-000791 AIDS000791 Adenosine, 2',3'-dideoxy-N,N-dimethyl- DMAPDDR N-6-dimethyl ddA N6,N6-Dimethyl-2',3'-dideoxyadenosine ddDMA ddMe2A