The straight forward synthesis of new carboxylic acids with hexahydro-oxaisoindolo[2.1-a]quinoline core from the 2,4-disustituted 1,2,3,4-tetrallydroquinolines bearing a furan fragment via the intramolecular Diels-Alder reaction has been proposed. It was demonstrated that synthesis of key precursors can be realized with excellent level of diastereoselectivity either by imino-Diels-Alder reaction or multi-component condensation approach.