A liquid-crystalline medium, preferably having a nematic phase, comprising one or more compounds of formula C ##STR00001##
the use thereof in an energy-efficient electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, displays of this type which contain a liquid-crystalline medium of this type, and the use of the compounds of formula C for improvement of the contrast and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.