We report a simple two-step method for the synthesis of a novel highly fluorescent benzothiophene-based dye comprising five fused rings and exhibiting a large Stokes shift (Δλ = 152 nm or Δν = 5482 cm -1in ethanol). Structural features of the obtained compound allow easy functionalization of the carbon core and open new possibility for the development of a series of new classes of fluorescent dyes.