In my diploma thesis I studied the syntheses of C-glucosaminyl-1,2,4-triazines and 1,2,4-triazin-5(4H)-ones. For the preparation of the target heterocycles C-(2-deoxy-2-phthalimido-3,4,6-tri-O-acetyl-β-D-glucopyranosyl)formamidrazone was prepared first. The reaction of O-peracylated C-glucosaminyl formimidate obtained from the corresponding formamide with hydrazine monohydrate provided this precursor in good yield. The synthesized sugar based heterocycles (after removal of the acyl protecting groups) are planned to subject to biological studies (e.g. enzyme inhibition and cytotoxic activities will be examined). Furthermore, study of the inverse electron-demand Diels-Alder cycloadditions of the 1,2,4-triazine derivatives are also envisaged.