6. Experimental protocols
6.1. Instrumentation and chemicals
All the chemicals and solvents employed in the synthesis were supplied by Merck (Germany), Fluka (Germany) and SD Fine chemicals (India) and used without purification. Melting points were determined on a digital melting point apparatus Electrothermal 1A 9200 (U.K.) and are uncorrected. All the reactions were monitored by TLC performed on 2.0–6.0 cm aluminum sheets precoated with AMD-070 gel 60 (HF-254, E. Merck, India). The IR spectra were recorded on a Shimadzu FTIR 8400S spectrophotometer (Kyto, Japan) using KBr optics. 1H NMR spectra were recorded in CDCl3 on a Varian Mercury YH-300 MHz spectrophotometer (Palo Alto, CA, USA) and chemical shifts (δ) are molecules given in ppm relative to TMS. Mass spectra were recorded at 70 eV on a Jeol D-300 spectrometer (Tokyo, Japan). Elemental analyses were carried out using FLASH EA 1112 CHN analyzer (Thermo Finnigan, Italy) and found within ± 0.4% of theoretical values.