Metformin was purchased from TSA, International (Indian
company), dipicH2, NaOH and ethanol were purchased from Merck IR spectrum was recorded on Perkin–Elmer 343 Spectrometer,
using the KBr disc technique. Melting points were determined with
an Electrothermal IA-900. 1H NMR and 13C NMR spectra were
obtained on Bruker 250 (250 and 62.5 MHz, respectively) spectrometer.
Chemical shifts were reported on the d scale relative to
TMS. Melting points were determined using an Electrothermal
IA-9100 apparatus and were not corrected.