摘要 |
The present invention relates to a process for the preparation of compounds of formula (I) wherein the substituents are as defined in claim 1, by a) reaction of a compound of formula (II) to form a compound of formula (III) b) reaction of that compound in the presence of a base to form a compound of formula (IV) c) conversion of that compound in the presence of a reducing agent into a compound of formula (I). |