synthesis of intermediates in the manufacture of class of drugs called tricyclic compounds applicable

摘要

The invention relates to a process for preparing a compound of formula (I), comprising reacting a bromo-substituted pyridine with an amine of the formula NHR5R6, reacting the resulting amide with an iodo-halomethyl-substituted compound and cyclizing the resultant product, wherein R, R1, R2, R3 and R4 are as defined in the specification; also claimed are a compound of formula (a), and a process for preparing it from the corresponding halo-substituted benzoic acid.