Synthesis methods and intermediates for the manufacture of Rizatriptan

摘要

The invention relates to a process for the manufacture of an 1,2,4-triazol-1-yl compound of the formula [A], or a salt thereof, wherein each of R3 and R4 is hydrogen or lower alkyl, said process comprising reacting a hydrazine compound of the formula [B] wherein R is hydrogen or acyl, R2 is hydrogen or a protecting group, are hydrogen or lower alkyl, and R6 is hydrogen or COOR7, or a salt thereof, with a 1,2,4-triazolyl forming reagent. In addition, novel intermediates for the synthesis of the anti-migraine agent Rizatriptan and methods for their synthesis are presented.