Excess molar enthalpies and heat capacities of dimethyl sulfoxide + 1,4-dioxane, dimethyl sulfoxide + 1,3-dioxolane, dimethyl sulfoxide+tetrahydropyran, dimethyl sulfoxide+tetrahydrofuran, dimethyl sulfoxide+1,2-dimethoxyethane, and dimethyl sulfoxide+1,2-diethoxyethane have been measured at 308.15 K and at atmospheric pressure using an LKB micro-calorimeter and a Perkin-Elmer differential scanning calorimeter. Heat capacities of pure components were determined in the range (293.15 < T/K < 423.15). The results of excess molar enthalpies were fitted to the Redlich-Kister polynomial equation to derive the adjustable parameters and standard deviations, and were used to study the nature of the molecular interactions in the mixtures. Results of excess molar enthalpy were interpreted by an extended modified cell model. (C) 2006 Elsevier B.V. All rights reserved.