The standard (p(o) = 0.1 MPa) molar enthalpies of combustion, at the temperature 298.15 K for crystalline N,N’-ethylenebis(4-aminopent-3-en-2-one), {CH3COCH:C(CH3)NHCH2 .}(2), H(2)ACACEN, and N,N’-ethylenebis(3-amino-1-phenylbut-2-en-1-one), H(2)BZACEN, {C6H5COCH:C(CH3)NHCH2 .}(2), were measured by static bomb-combustion calorimetry in oxygen. The standard molar enthalpies of sublimation of both compounds were measured by effusion techniques. These values were used to derive the standard molar enthalpies of formation of the compounds, in both the crystalline and the gaseous phases.