The invention relates to single stranded DNA inhibitors of APOBEC3 enzymes and uses thereof. The compounds of the invention comprise β-D-5-O-phosphato-2-deoxyribofuranosyl analogues of nucleoside-like inhibitors of cytidine deaminase, flanked by oligonucleotide sequences which may be cross-linked. The compounds of the invention may have therapeutic application against diseases and conditions in which inhibition of a human cytidine deaminase of the APOBEC3 family would be beneficial.