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Compounds containing the 1,2,4-triazine moieties are largely used as pharmaceuticals, dyes, pesticides, and herbicides. Great interest is directed to the synthesis of the title heterocycles having potentially useful biological properties. A large number of 1,2,4-triazines that are condensed with one or more heterocycles are well known and a wide variety of synthetic methods for their preparations are available. This chapter illustrates the triazines that are fused to heterocycles with three, four, and five-membered rings. It covers the survey of the literature of these condensed compounds from 1974 to 1992. The parent compound of this series has two Kekule structures. It can be fused with other heterocycles at its six different sites. The 1,2,4-triazine ring can also constitute a central unit in a condensed ring system, where two or more faces are included in fusions. It is noted that the heterocycles having …