Phospholipid conjugates of 3′-azido-3′-deoxythymidine (AZT) show activity against human immunodeficiency virus (HIV) in vitro. Here we report on the synthesis and characterization of two pyrene containing conjugates: 2-N-(4-(pyren-1-yl) butanoyl) ceramide 5′-phosphothymidine (Pbs–Cer–P–T)(XII) and 2-N-(10-(pyren-1-yl) decanoyl) ceramide 5′-phosphothymidine (Pds–Cer–P–T)(XIII). These fluorescent labelled ...