| 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 alkyl, which comprises, reaction of a compound of structure (II), in which R<1> is alkyl, phenyl or substituted phenyl and n is 1 to 3, with an amine HNR2 in which R is as described for structure (I), and optionally thereafter forming a salt.n[WO9116306A1] |