| abstract |
A process for the preparation of compounds of formula (1), wherein R 1 is C 1 -C 6 alkyl and X is hydrogen, a hydrocarbon radical or a cation, wherein a compound of formula (2), wherein R 1 is as defined above and R 2 is hydrogen or a hydrocarbon radical, is reduced, the resulting compound of formula (3) is reacted with a compound that introduces the radical of formula —CH 2 —COOR 3 , wherein R 3 has the meanings given above for R 2 , and the resulting compound of formula (4) is reduced and optionally hydrolysed. |