| 摘要 |
<p>[Subject] The object of the present invention is to provide new intermediates (IIa) and (III) of the 6-substituted-1-methyl-1-H-benzimidazol derivatives (I) which are publicly known pharmaceutically active ingredients, and a preparation procedure suitable for a large scale synthesis of N-(5-substituted-2-nitrophenyl)-N-methylamines (II) which are synthetic intermediates. Additionally, another object of the present invention is to provide an efficient procedure for the preparation of the 6-substituted-1-methyl-1-H-benzimidazole derivative (I) from said synthetic intermediates (II) in a shorter number of steps. [Measures to solve the subject] The present invention relates to a procedure for the preparation of a compound (I) represented by the following formula and synthetic intermediates of said compound (I). (In the above reaction scheme, R 2 represents a phenyl group which may optionally be substituted with substituents such as a C 1 -C 6 alkyl group or the like, and X represents an oxygen atom, a sulfur atom or a nitrogen atom).</p> |
