p-Toluenesulfonic acid → HCID 54501125, compound
Reaction equation
[CH:1]([S:4]([N:7]1[C:11]2[CH:12]=[C:13]([C:16](O)([CH2:23][C:24]([O:26][CH3:27])=[O:25])[C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)[CH:14]=[CH:15][C:10]=2[N:9]=[C:8]1[NH2:29])(=[O:6])=[O:5])([CH3:3])[CH3:2].C1(C)C=CC(S(O)(=O)=O)=CC=1>C(Cl)(Cl)Cl>[CH:1]([S:4]([N:7]1[C:11]2[CH:12]=[C:13]([C:16](=[CH:23][C:24]([O:26][CH3:27])=[O:25])[C:17]3[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=3)[CH:14]=[CH:15][C:10]=2[N:9]=[C:8]1[NH2:29])(=[O:5])=[O:6])([CH3:2])[CH3:3]Participants
4
Procedure
A solution of 6.0 g. of 1-isopropylsulfonyl-2-amino-6-(α-hydroxy-α-methoxycarbonylmethylbenzyl)benzimidazole (from Example 4) and 6.0 g. of p-toluenesulfonic acid in 150 ml. of chloroform was heated at reflux for three hours. The solution was cooled to room temperature and washed two times with saturated aqueous sodium bicarbonate solution, and two times with water. After drying the solution over sodium sulfate, the solvent was removed by evaporation under reduced pressure to provide 5.5 g. (96% yield) of 1-isopropylsulfonyl-2-amino-6-(α-methoxycarbonylmethylenebenzyl)benzimidazole. M.P. 160°-165° C.