Abstract: Disclosed are aromatic condensation compounds useful as building blocks for construction of various types of optically active substances and reagent, wherein the aromatic condensation compounds are represented by general formula (1) below and capable of forming enantiomeric isomers. In the formula, two Rs are the same or different functional groups and selected from among linear, branched and cyclic hydrocarbon groups of 1-16 carbon atoms, either of which R may be hydrogen. A portion of the aromatic nucleus may be reduced, or at least one of the two nitrogen atoms may be quaternary. The aromatic condensation compounds can be produced by heating and reacting N,N'-diphenyl-p-phenylenediamine with a carboxylic acid represented by the general formula --RCOOH in an amount of at least 2 molar equivalents with respect to the diamine, at 180-210.degree. C. in the presence of a Lewis acid such as zinc chloride.