Schiff base Color M.Wt Melting point (°C) Yield % Crystallization Solvent VIII yellow 504 >300 60 DMF, EtOH (9:1) IX yellow 516 >300 65 DMF, EtOH (9:1) X yellow 544 >300 80 DMF, EtOH (9:1) XI yellow 536 >300 75 DMF, EtOH (9:1)

Table 1: Color, molecular weight and melting point of macrocyclic hydrazone (VIII, IX, X, XI).