Abstract: A novel compound which exhibits superior effectiveness particularly in reducing the driving voltage of liquid crystal display elements, and a liquid crystal composition containing the same are provided, which compound is a 5-alkyl-2-(3,4-difluorophenyl)pyrimidine expressed by the formula ##STR1## wherein m represents an integer of 1 to 8.

Abstract: A novel 1,4-dipyrimidinylbenzene derivative which is useful as a component constituting a liquid crystal composition which is superior in properties and also physically and chemically stable, as a material for liquid crystal display elements, and a liquid crystal composition containing the same are provided, which derivative is expressed by the formula ##STR1## wherein X represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms, methylthio group or cyano group and Y represents an alkyl group or an alkoxy group each of 1 to 10 carbon atoms.

Abstract: Ester compounds having a pyrimidine ring, using as their raw material, substituted pyrimidinols in place of expensive p-substituted phenols, and also useful as a material for liquid crystal display elements are provided which esters are expressed by the general formula ##STR1## wherein R represents an alkyl or alkoxy group of 1 to 10 carbon atoms; X represents a halogen atom of F, Cl or Br, cyano group or an alkyl or alkoxy group of 1 to 10 carbon atoms; ##STR2## represents ##STR3## and n is 0 or 1.

Abstract: A novel bipyrimidinyl derivative which is superior in practical properties and useful as a high temperature liquid crystal component constituting a physically and chemically stable liquid crystal composition is provided, which bipyrimidinyl derivative is a 2,5'-disubstituted-5,2'-bipyrimidinyl expressed by the formula ##STR1## wherein ##STR2## X represents a halogen atom of F, Cl or Br or cyano group or an alkyl group or an alkoxy group each having 1 to 10 carbon atoms and R represents an alkyl group or an alkoxy group each having 1 to 10 carbon atoms.

Abstract: Novel compounds capable of improving various characteristics required for liquid crystal compositions when added to liquid crystal substances, and liquid crystal compositions containing the same are provided, which novel compounds are halogenopyrimidine derivatives expressed by the general formula ##STR1## wherein R.sup.1 represents an alkyl group of 1 to 10 carbon atoms, R.sup.2 represents a halogen atom of F, Cl of Br and l represents 1 or 2.

Abstract: Novel organic compounds useful as a component of liquid crystal compositions are provided which compounds are 5-substituted-2-(4'-substituted biphenylyl)pyrimidines and 5-substituted-2-[4'-(trans-4"-substituted cyclohexyl) phenyl]pyrimidines expressed by the general formula ##STR1## wherein R.sub.1 and R.sub.2 each represent an alkyl group or an alkyloxy group having 1 to 10 carbon atoms and ##STR2## represents cyclohexane ring or benzene ring.