Four chiral compounds have been synthesized. Their phase transition behavior was investigated by differential scanning calorimetry and polarized optical microscopy. Two of them show monotropic smectic C* phases. Moreover, one of them shows an enantiotropic blue phase. The lateral fluoro-substitution strongly suppressed the formation of SmC* phases and decreased clearing points. Although the introduction of nitro group in the core decreased the length-diameter ratio, the temperature range of monotropic SmC* phase did not change much.