Abstract 1-(4-(3-(Trifluoromethyl)-3 H-diazirin-3-yl) benzamido)-3-O-(4, 4"-dimethoxytrityl)-2, 3-propanediol phosphoramidite was synthesized and used as a modified unit in the automatic synthesis of oligodeoxyribonucleotides. Pentadecathymidylates with various numbers of 2, 3-propanediol moieties substituted with aryl (trifluoromethyl) diazirinyl (ATFMD) were obtained, and the thermal stability of their duplexes with (dA) 15 were ...