Synthesis of benzopyranotriazoles.

摘要

A process for preparing a compound of formula (I)
wherein X is phenyl optionally substituted by one halogen, C_1-4 alkyl or C_l-₄ alkoxy; or pyridyl; R¹ is hydrogen or C_1-6 alkyl; and n is an integer of from 1 to 6; which process comprises, cyclising a compound of formula (II)
wherein X, R¹ and n are as defined in relation to formula (I); Y is an hydroxy or an acid activating group and R^x is hydrogen or an N- protecting group and thereafter if desired carrying out one or more of the following steps: (i) removing any protecting group R^x, (ii) preparing a salt of the compound of formula (I).