substituted active methylene compounds by classical Knoevenagel condensation reaction to obtain novel monostyryl dyes and a bis-styryl dye . These novel styryldyes have hue varying from orange to violet. The dyes were applied to polyester fibers. The spectral and thermal characteristics of the dyes and fastness properties of the dyed polyester fabric were investigated. J. Heterocyclic Chem., 46, 221 (2009)