| 主权项 |
1. A method for preparing 2-(N-substituted)-amino-benzimidazole derivatives, comprising the steps of:
(1) reacting a compound of 2-(N-protecting group)-O-aryl diamine of the following formula II:with a compound of N-phenoxycarbonyl monosubstituted amine of the following formula III:to produce a compound of 2-(N-protecting group)-amino aryl urea of the following formula IV: (2) dissolving the compound of 2-(N-protecting group)-amino aryl urea obtained in step (1) in an organic solvent and adding dichloro triphenylphosphine or dibromo triphenylphosphine to the resulting solution, then performing a dehydrating cyclization reaction of the compound of 2-(N-protecting group)-amino aryl urea in the presence of an organic base to produce a compound of 1-protecting group-2-(N-substituted)-amino-benzimidazole of the following formula V:the organic solvent being selected from the group consisting of alkanes, aromatic hydrocarbons, halogenated aromatic hydrocarbons, nitriles, ethers and halogenated alkanes, or any combination thereof; and
(3) deprotecting the compound of 1-protecting group-2-(N-substituted)-amino-benzimidazole obtained in step (2) to obtain a compound of 2-(N-substituted)-amino-benzimidazole derivatives of the following formula I:wherein
R1 is selected from the group consisting of H, alkyl, aryl, aralkyl, halogen, alkoxy, alkylthio, aryloxy, arylthio, a cyano group, alkylcarbonyl, aroyl, and any combination thereof, R2 is selected from the group consisting of of alkylsulfonyl, cycloalkyl sulfonyl, aryl sulfonyl, and trifluoroacetyl, and R3 is selected from the group consisting of alkyl, aryl, aralkyl, cycloalkyl, cycloalkyl-alkyl, heteroaryl, heteroarylalkyl, and hetercycloalkyl;wherein the dichloro triphenylphosphine is prepared by triphenylphosphine oxide with oxalyl chloride or diphosgene or triphosgene; andwherein the dibromo triphenylphosphine is prepared by triphenylphosphine oxide with bromine. |
