3,4-Diaminobenzoic acid → 4-Amino-3-(1-methyl-4-nitro-2-pyrrolecarboxamido)benzoic acid
Reaction equation
[CH3:1][N:2]1[CH:6]=[C:5]([N+:7]([O-:9])=[O:8])[CH:4]=[C:3]1[C:10](=[O:15])C(Cl)(Cl)Cl.[NH2:16][C:17]1[CH:18]=[C:19]([CH:23]=[CH:24][C:25]=1[NH2:26])[C:20]([OH:22])=[O:21]>>[NH2:16][C:17]1[CH:18]=[C:19]([CH:23]=[CH:24][C:25]=1[NH:26][C:10]([C:3]1[N:2]([CH3:1])[CH:6]=[C:5]([N+:7]([O-:9])=[O:8])[CH:4]=1)=[O:15])[C:20]([OH:22])=[O:21].[NH2:26][C:25]1[CH:24]=[CH:23][C:19]([C:20]([OH:22])=[O:21])=[CH:18][C:17]=1[NH:16][C:10]([C:3]1[N:2]([CH3:1])[CH:6]=[C:5]([N+:7]([O-:9])=[O:8])[CH:4]=1)=[O:15]Participants
Procedure
As a further alternative, the compound of the formula (14) can also be synthesized as will be described next. For example, 1-methyl-4-nitro-2-pyrrolecarboxylic acid is reacted, by using the process disclosed in Tetrahedron, 34, 2389-2391(1978), with thionyl chloride into 1-methyl-4-nitro-2-pyrrolecarboxylic acid chloride, which is then reacted with a 3,4-diaminobenzoic acid to obtain 3-amino-4-(1-methyl-4-nitro-2-pyrrolecarboxamido)benzoic acid or 4-amino-3-(1-methyl-4-nitro-2-pyrrolecarboxamido)benzoic acid as the exemplified compound. Here, the reaction product can also be a mixture of both the benzoic acids. Methylene chloride, chloroform, DMF or the like can be used as a solvent. Other solvents are also usable as long as they do not take part in the reactions. Heating of the thus-obtained amide compound with trilfluoroacetic acid with any solvent, which do not participate in the reaction, provides 1H-2-(1-methyl-4-nitropyrrol-2-yl)benzimidazole-5-carboxylic acid. Further, 1-methyl-4-nitro-2-trichloroacetylpyrrole which is a known compound disclosed in Heterocycles, 27, 1945-1952(1988) is likewise reacted with 3,4-diaminobenzoic acid to obtain 3-amino-4-(1-methyl-4-nitro-2-pyrrolecarboxamido)-benzoic acid or 4-amino-3-(1-methyl-4-nitro-2-pyrrolecarboxamido)benzoic acid. Here, the reaction product can also be a mixture of both the benzoic acids. The reaction product can also be converted into 1H-2-(1-methyl-4-nitropyrrole-2-yl)benzimidazole-5-carboxylic acid likewise. The reaction can also be conducted similarly by using as a starting material an equivalent carboxylic acid other than 1-methylpyrrole-2-carboxylic acid.
Sources & evidence
- ORD record
- ord-7c6d7fb59c9f4203b2a13b097e156485
- Source dataset
- uspto-grants-1998_12
- Patent number
- US05852011
Reaction notes
Loading…