SYNTHESIS AND PHARMACOLOGY OF 2-(2-AMINOETHYL)IMIDAZOLE (2-ISOHISTAMINE)

The compound prepared by Jones, which was assigned the structure 2-(2-aminoethyl)imidazole (3), is actually 5-aminomethyl-2-methylimidazole (14). Authentic 3 has been synthesized from l-benzyl-2-chloromethylimidazole (7) by cyanide displacement in DMSO to yield nitrile 10, followed by reduction to the amine 12 and debenzylation. Reaction of 1-benzyl-2-lithioimidazole (15) with N-(2-bromoethyl)phthulimide (16) gave 2-(2-aziridinocarbonylbenzoyl)-1-benzylimidazole (19) rather than the expected alkylation product 17. Compound 3 has weak histamine-like activity on smooth muscle and on blood pressure but none on gastric secretion. © 1968, American Chemical Society. All rights reserved.