Tga 50 unit

Melting points were recorded using a digital Gallenkamp (SANYO) model MPD.BM 3.5 apparatus and are uncorrected. 1 H NMR and 13 C NMR spectra were determined in DMSO-d solution at 300 and 75.5 MHz respectively using a Bruker AM-300 spectrophotometer. Mass Spectra (EI, 70 eV) were taken on a GC-MS, Agilent technologies 6890 N with an inert mass selective detector 5973 mass spectrometer and elemental analyses were conducted using a LECO-183 CHNS analyzer.
Fourier transform infrared spectroscopy (FTIR), spectra were recorded on an FTS 3000 MX spectrophotometer (Pakistan).
Infrared spectra were recorded in KBr pellets with a resolution of 2 cm À1 in the 4000-400 cm À1 range on a Bruker EQUINOX 55 FTIR spectrometer (Argentina). The FT-Raman spectra were recorded in the region 4000-100 cm À1 using a Bruker IFS 66v spectrometer equipped with Nd:YAG laser source operating at 1.064 lm line with 200 mW power of spectral width 2 cm À1 . UV-Vis spectra in DMSO solution were recorded using a standard quartz cell placed in the sample compartment of a UV-Vis Hewlett-Packard 8454-A diode array spectrometer (2 nm resolution).
Thermal analyses were performed with Shimadzu TGA-50 unit, between room temperature and 500 °C, at a heating rate of 5 °C/min and nitrogen flow of 50 ml/min.

Thin layer chromatography (TLC) was performed on 0.25 mm silica gel pre-coated plastic sheets (40/80 mm) (Polygram SIL G/UV254, Macherey & Nagel, Düren, Germany) using benzene/methanol (9/1) as eluent. The IR spectra were recorded on a FT-IR Bomem-Michelson 102 spectrometer, in KBr pellets with a resolution of 2 cm -1 in the 4000-400 cm -1 range. Raman spectra for compounds I and II were recorded using a Horiba Jobin Yvon T64000 Raman spectrometer equipped with a liquid N 2 -cooled back-thinned CCD detector. Spectra were recorded as the co-addition of up to 16 individual spectra with CCD exposure times of 10-20 s each. 1 H and 13 C NMR spectra were recorded on a Bruker DRX 400 MHz, internally referenced to TMS, chemical shift (δ), multiplicity (m), spin-spin coupling constant (J), integral (I) are given. CDCl 3 was used as solvent. Partial elemental analyses were carried out in an instrument of CHNS staff EA 1108 of the FISONS. Thermal analyses were performed with Shimadzu TGA-50 unit, between room temperature and 750 °C, at a heating rate of 5 °C/ min and nitrogen flow of 50 mL/min.