A combined experimental and theoretical study of the fundamental thermodynamic parameters of 3-(5-phenyl-1-(pyridin-3-yl)-1H-pyrrol-2-yl)propanoic acid was carried out for the first time. The enthalpies of combustion, formation in the condensed state, fusion, and vaporization were determined using high-precision equipment. Based on the experimentally obtained results, the enthalpies of sublimation and formation in the gaseous state at 298.15 K were calculated using two methods. The possibility of applying analytical methods of Domalski, Joback and quantum chemical calculations to determine the enthalpy of formation in the gas phase is analysed.