1- ( beta-d-arabinofuranosyl ) uracil ( arau ) and 1- ( beta-d-arabinofuranosyl ) thymine ( arat ) were comparable to thymidine as permeants while nucleosides in which the 3'-hydroxyl was replaced with hydrogen or a halogen had a decreased affinity for the transporter .
C0041917
uracil
C0040087
thymine