Symmetrical cyanurate heterocycle

Triazines, formerly symmetric or 5-triazines, have been known for almost 200 years, and are, like many heterocyclic compounds, often referred to by trivial names. Common trivial names used include cyanuric acid (2,4,6-trihydroxy-l,3,5-triazine (1)), cyanurates (2,4,6-trialkoxy-1,3,5-triazines (2)), cyanuryl chloride (2,4,6-trichloro-l,3,5-triazine (3)), isocyanurates (1,3,5-trialkyl-... 

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