Long chain N-alkyl amino and imino compounds, oxa-substituted derivatives thereof, and pharmaceutical compositions including such compounds are described. The long chain N-alkyl group is a C8-C16 alkyl group. The long chain N-alkyl compounds and oxa-substituted derivatives thereof can be used in the treatment of viral infections, in particular hepatitis B virus or hepatitis C virus, in a cell or an individual. For example, the long chain N-alkyl compounds or oxa-substituted derivatives thereof can be derived from piperidines, pyrrolidines, phenylamines, pyridines, pyrroles, or amino acids.