73733-91-2

Upstream product

• 39742-60-4 1-(2-phenylethyl)-4-piperidinone 
• 75-31-0 isopropylamine 
• 24089-69-8 8-Phenethyl-1,4-dioxa-8-aza-spiro[4.5]decane; hydrochloride 

Downstream Products

• 73736-37-5 (1-Benzyl-1H-benzoimidazol-2-yl)-isopropyl-(1-phenethyl-piperidin-4-yl)-amine 
• 98245-08-0 (1-Ethyl-1H-benzoimidazol-2-yl)-isopropyl-(1-phenethyl-piperidin-4-yl)-amine 
• 73733-96-7 N'-(2-aminophenyl)-N-(1-methylethyl)-N-<1-(2-phenylethyl)-4-piperidinyl>thiourea 
• 73736-03-5 N-(1-methylethyl)-N-<1-(2-phenylethyl)-4-piperidinyl>-1H-benzimidazol-2-amine 
• 73733-92-3 N-(1-methylethyl)-N'-(2-nitrophenyl)-N-<1-(2-phenylethyl)-4-piperidinyl>thiourea 

Relevant academic research and scientific papers

New antihistaminic N-heterocyclic 4-piperidinamines. 1. Synthesis and antihistaminic activity of N-(4-piperidinyl)-1H-benzimidazol-2-amines

The synthesis of a series N-(4-piperidinyl)-1H-benzimidazol-2-amines and the preliminary evaluation of their in vitro and in vivo antihistaminic activity are described. Cyclodesulfurization of (2-aminophenyl) thioureas with mercury(II) oxide resulted in 2-aminobenzimidazole intermediates, which were monoalkylated on the endo-nitrogen atom. After deprotection of the piperideine nitrogen atom with 48% aqueous hydrobromic acid solution, the title compounds were obtained by three different methods, viz. alkylation, reductive amination, or oxirane ring-opening reactions. The in vivo antihistaminic activity was evaluated by the compound 48/80 induced lethality test in rats and histamine-induced lethality test in guinea pigs after oral and/or subcutaneous administration. The duration of action, for a selected number of compounds, was studied in the guinea pig. The phenylethyl derivatives showed the most potent antihistamine properties after oral administration in both animal species.