*3.2. Di*ff*erential Scanning Calorimetry (DSC)*

The melting point and heat of fusion of samples were determined using DSC instrument (model Q2000, TA Instruments, New Castle, DE, USA) equipped with a refrigerated cooling system. The instrument was operating with TA Universal Analysis ® software (version 4.5 A) and calibrated initially for temperature and heat flow using high purity standard of indium. The sample (2−4 mg) was analyzed in a Tzero aluminium pan crimped with a lid. The weight of sample was accurately recorded on a microbalance (Sartorius GM 1202, Goettingen, Germany). Each sample was subjected to thermal scanning at a heating rate of 10.0 ◦C/min. The purge of dry nitrogen at flow rate of 50 mL/min was maintained during analysis.
