Abstract Herein we describe the synthesis of novel tricyclic analogues issued from the rigidification of the methoxy group of the benzofuranic analogue of melatonin as MT 1 and MT 2 ligands. Most of the synthesized compounds displayed high binding affinities at MT 1 and MT 2 receptors subtypes. Compound 6b (MT 1, K i= 0.07 nM; MT 2, K i= 0.08 nM) exhibited with the vinyl 6c and allyl 6d the most interesting derivatives of this series. ...