The crystal structure of 4,4'-substituted salicylideneaniline C10H21O–C6H3(OH)–CH=N–C6H4–C7H13 has been investigated by X-ray diffraction. A high degree of disorder of both alkyl chains is revealed. The crystal packing consists of alternating loose aliphatic and closely packed aromatic regions. Weak directional interactions of the С–Н···π type are found in aromatic regions. Specific features of the mesogenic compound crystal packing preceding the mesophase, melting of these compounds, and the formation of mesophase upon isotropic melt cooling are discussed based on the X-ray diffraction and differential scanning calorimetry data.