New, non‐imidazole histamine H3 receptor antagonists were prepared and in vitro tested as H3 receptor antagonists measured as the electrically evoked contraction of the guinea‐pig jejunum. The 2‐(1‐piperidinyl)‐ and 2‐(1‐pyrrolidinyl)benzothiazoles show no or very poor activity; 2‐[1‐(4‐amino)piperidinyl]‐ and 2‐(1,2‐ethanediamino)‐ and 2‐(1,3‐propanediamino)derivatives of benzothiazole possess weak