90518-51-7

Upstream product

• 90518-50-6 4-[1-Benzyl-3-(2-nitro-phenyl)-thioureido]-piperidine-1-carboxylic acid ethyl ester 
• 90539-29-0 4-Benzylamino-piperidine-1-carboxylic acid ethyl ester 
• 2719-30-4 o-nitrophenylisothiocyanate 

Downstream Products

• 73736-47-7 Benzyl-(1-benzyl-1H-benzoimidazol-2-yl)-(1-phenethyl-piperidin-4-yl)-amine 
• 98245-09-1 Benzyl-(1-ethyl-1H-benzoimidazol-2-yl)-(1-phenethyl-piperidin-4-yl)-amine 
• 73736-05-7 N-[1-(2-phenylethyl)-4-piperidinyl]-N-(phenylmethyl)-1H-benzimidazol-2-amine 

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.