abstract |
A process for the preparation of a compound of structure (i)in which n is 1 to 3 and each group r is hydrogen or c1-4alkyl, which comprises, reaction of a compound of structure (ii)in which r1 is c1-4alkyl, phenyl or substituted phenyl and n is 1 to 3, with an anime hnr2 in which r is as described for structure (i), and optionally thereafter forming a salt. |