Two new 5'-phosphorylated derivatives of 3'-azido-3'-deoxythymidine (AZT), namely alpha,beta;beta,gamma-bis (methylene) AZT-5'-triphosphate (1) under bar and alpha,beta-propylene AZT 5'-diphosphate (2) under bar, were synthesized. When evaluated for their inhibitory effects on human immunodeficiency virus (HIV) reverse transcriptase, these compounds were about 1000-fold less active than AZT-5'-triphosphate (AZTTP) as competitive inhibitors of this enzyme.