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We would like to thank to Prof. Karl Gatterer, PTC/TU Graz, for
IR spectra and Prof. Robert Saf, ICTM/TU Graz, for mass spectrome-
try. Thanks are due to Mr. Sarfraz Ahmad, Dept. of Pharmaceutical
Chemistry, Uni-Graz, for the NMR spectra. M.Z. highly acknowl-
edges financial support from the Higher Education Commission
Pakistan.
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