What is any one of a certain series of basic compounds containing a chain of four nitrogen atoms; for example, ethyl tetrazone, (C2H5)2N.N2.N(C2H5)2, a colorless liquid having an odor of leeks called?

tetrazone — Any one of a certain series of basic compounds containing a chain of four nitrogen atoms; for example, ethyl tetrazone, (C2H5)2N.N2.N(C2H5)2, a colorless liquid having an odor of leeks. (Webster's 1913.)

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