Synthesis of New Heterocyclic Compounds Starting from 2-Aminopyridine

The synthesis part of this work is divided into three different parts: Part One: This part involved the synthesis of 3-biphenyl-4-ylimidazo[1,2-a]pyridine [1], 3-phenylimidazo[1,2-a]pyridine [2], and other compounds, directly from the starting material. Part Two: This part involved the synthesis of N-carbamoyl-N2-pyridin-2-ylglycinamid [12], N-(4-biphenyl-4-yl-1,3-oxazol-2-yl)-N2-pyridine -2-ylglyciamide [13], and other compounds, from the reaction of 2-aminopyridine with ethylchloroacetate to yield ethyl-N-pyridin-2-ylglycinate [11], this compound was used as precursors. Part Three: This part involved the synthesis of 2-[(pyridine-2-ylamino)methyl]-4,5-dihydro-6H-1,3,4- oxadiazine-6-one [17], 3-[(pyridine-2-ylamino)methyl]1,6-dihydro-1,2,4- triazin-5(2H)-one [18], 5-[(pyridine-2-ylamino)methyl]-1,3,4-oxadiazole-2- thiol [19], and other compounds, starting from 2-(pyridine-2-ylamino)acetohydrazide [16]. This compound was prepared from refluxing ethyl-N-pyridin-2-ylglycinate [11] with hydrazine hydrate.