3'-Carboxymethyl-3'-deoxyadenosine derivatives were prepared from 2'-O-TBDMS-3'-[(ethoxycarbonyl)methyl]-3'-deoxyadenosine (6) via simple and efficient procedures. Conversion of 6 to its 5'-azido-5'-deoxy derivative 9 was accomplished via a novel one-pot method employing 5'-activation (TosCl) followed by efficient nucleophilic displacement with tetramethylguanidinium azide. Compound 9 was converted to 5'-[(N-methylcarbamoyl)amino] derivative 12 via one-pot reduction/acylation employing H₂/Pd-C followed by treatment with p-nitrophenyl N-methylcarbamate.  N⁶-phenycarbamoyl groups were introduced by treatment with phenylisocyanate, and an efficient new method for lactonization of 2'-O-TBDMS-3'-[(ethoxycarbonyl)methyl]-3'-deoxyadenosines to give corresponding 2',3'-lactones was also developed.  Target compounds were evaluated for anti-HIV and HIV integrase inhibitory activities.  None of the compounds showed activities against HIV or HIV integrase at the concentrations tested. Cytotoxicities of several of the target compounds suggested some promise as potential antitumor agents, and screening for such activities is currently in progress.