collidine

:  any of a number of organic bases C₈H₁₁N that are the trimethyl, methyl-ethyl, and propyl homologues of pyridine, that are in general pungent oily poisonous liquids, and are obtained chiefly as by-products in the coking process or are synthesized: such as a :  the liquid symmetrical trimethyl homolog made by reaction of acetone and ammonia and used as a solvent in chromatography —called also s-collidine, 2,4,6-collidine, 2,4,6-trimethylpyridine b :  methylethylpyridine