What is (a) Pertaining to, or derived from, isonicotine. (b) Pertaining to, or designating, an acid isomeric with nicotinic acid called?

isonicotinic — (a) Pertaining to, or derived from, isonicotine. (b) Pertaining to, or designating, an acid isomeric with nicotinic acid. (Webster's 1913.)

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