CS230343B1 - Amides derived from 2-aminobenzimidazole - Google Patents

Description

The invention relates to amides derived from 2-aminobenzimidazole of the general formula I

wherein the RCO group is 1- (p-chlorobenzoyl) -5-methoxy-2-methyl-3-indolyl acetic acid, benzyl, diphenylacetic, 4-chlorophenylacetic, 4-methoxyphenylacetic, 4-fluorophenylacetic, 4-nitrophenylacetic acid, 3, 4-dimethoxyphenylacetic, phenoxyacetic, 2-chlorophenoxyacetic, 4-chlorophenoxyacetic, 2,4-dichlorophenoxyacetic, phenoxyisobutyric, 4-chlorophenoxyisobutyric, 4-chlorobenzoic, nicotinic and isonicotinic.

Compounds of formula I that are novel have been tested for analgesic activity in comparative tests with aminophenazone (1-phenyl-2,3-dimethyl-4-dimethylamino-5-pyrazolone). 1j, which showed significant analgesic activity in the above assays with substantially lower toxicity than the standard.

The invention also relates to a process for the preparation of the compounds of the formula I. According to the invention, the compounds of the formula I are prepared, for example, by first preparing an acid of the formula II

RCOOH (II).

in which the RCO-group denotes the same as in formula I, by reaction with Ι, Γ-carbonyldiimidazole, the corresponding imidazolide, which reacts in situ with the 2-aminobenzimidazole of formula III

The reaction is preferably carried out in dichloromethane at room temperature and is complete in 24 h.

All intermediates used are known and can be prepared by known methods.

Details of the embodiment are given in the following examples.

He did

To a solution of 0.02 mol of Ι, Γ-carbonyldiimidazole in 50 ml of dichloromethane was added at room temperature 0.02 mol of 1- (p-chlorobenzoyl) -5-methoxy-2-methyl-3-indolylacetic acid, stirred for 5 minutes and to the thus prepared imidazolide is added 0.02 mol of 2-aminobenzimidazole. Stirring at room temperature is continued for 6 h, the mixture is left until the next day, the precipitated crystals are filtered off with suction, washed with dichloromethane and recrystallized from 2-propanol. 4.2 g of the desired amide is obtained, m.p. 216-217 ° C. (Fabric 1)

Table 1 (substances 2 to 17)

Fabric R

Example 2

In the same manner as described in Example 1, amides 2 to 17 are prepared. The process for isolating amides 3, 9, 10, 13 and 14 differs from that described in that the product does not crystallize from the reaction mixture but is obtained as a residue after washing several times with dichloromethane. of water and distilling off the solvent to dryness under reduced pressure. Crystallization of the residue from a suitable solvent gives the pure material.

Mp. ° C Solvent (C6 _H5) 2 C (OH) (C ₆ H ₅₎ 2 CH

4-ClC6H4Cl-I2

4 CH3OC6IT4CH2

4-FC6H4CH2

4-NO2C8H4CH2

3,4- (CH 3 O) and C 8 H 3 CH 2

C6H5OCH2

2-CIC 6 H 4 OCH 2

4-CIC 6 H 4 OCH 2

2,4-Cl 2 C 6 H 3 OCH 2

CsH5OC (CH3) 2

4-ClC6H4OC (CH3) 2

4-C1C6H4

Claims (1)

Subject Amides derived from 2-aminobenzimidazole of general formula I 245 to 247 methyl alcohol 215 to 216 nitromethane 272 to 273 methylcellosolv 263 to 264 methylcellosolv 245 to 246 2-Propanol 233 to 235 nitromethane 218 to 219 toluene 202 to 203 2-Propanol 193 to 194 2-Propanol 220 to 221 2-Propanol 217 to 218 2-Propanol 136 to 137 benzene: heptane 140 to 141 benzene: heptane 251 to 252 2-Propanol 301 to 302 methylcellosolv 309 to 310 methylcellosolv YNALEZU 2. Method production of amides according to point of the formula I, characterized in that: an acid of formula II RCOOH (II) in which the group RCO - denotes the same as in formula I is converted by reaction with Ι, Γ-carbonyldiimidazole to the corresponding imidazolide, which is further reacted in situ with 2-aminobenzimidazole of formula III in which RCO - denotes the acid residue 1- ( p-chlorobenzoyl) -5-methoxy-2-methyl-3-imdolylacetic, benzyl, diphenylacetic, 4-chlorophenylacetic, 4-methoxyphenylacetic, 4-fluorophenylacetic, 4-nitrophenylacetic, 3,4-dimethoxyphenylacetic, phenoxyacetic, 2-chlorophenoxy, -chlorophenoxyacetic, 2,4-dichlorophenoxyacetic, phenoxyisobutyric, 4-chlorophenoxyisobutyric, 4-chlorobenzoic, nicotinic and isonicotinic.