Novel amphiphilic molecules, derivatives of gallic acid combining three hydrophilic 3,4-dihydroxypropyloxy (1-glyceryl) groups and one alkyl chain via central aromatic linking units (N-alkyl-3,4,5-tris(3,4-dihydroxypropyloxy)benzamides and n-alkyl 3,4,5-tris(3,4-dihydroxypropyloxy)benzoates) have been synthesized. Their thermotropic and lyotropic phase behavior was investigated by hot stage polarized light optical microscopy, by differential scanning calorimetry, and in some cases by X-ray scattering. Lamellar (S-A), type-1 bicontinuous cubic (Cub(V1)), and type-1 hexagonal columnar (Col(h1)) mesophases have been found for the solvent-free compounds solely in dependence on the length of their alkyl chains. Hence, with the exception of the micellar cubic phase (Cub(I1)) all main mesophase types found in normal (type-1) lyotropic systems have been successfully realized as their thermotropic analogues in the absence of any solvent. Additionally, binary systems of different amphiphiles have been investigated. In these systems phase sequences were obtained, which resemble those of lyotropic systems. The analysis of the induced phases is proposed to be also a useful tool to assign the phase structure of thermotropic cubic mesophases. On addition of protic solvents Col(h1) phases were introduced or stabilized, but no micellar cubic phases were found.