Acene-thiophene compounds are disclosed that are useful as organic semiconductors. The compounds, when used as the semiconductor layer in organic thin-film transistors exhibit device characteristics, like charge-carrier mobilities and current on/off ratios, that are comparable to those of pentacene. Also described are semiconductor devices comprising at least one compound of the invention; and articles comprising the semiconductor devices such as thin film transistors or transistor arrays, and electroluminescent lamps.