Patent ID: 7368101
Filing Date: 2008-05-06
Classification: C07C

Abstract:
1. Process for the preparation of (S)-N,N′-bis[2-hydroxy-1-(hydroxymethyl)ethyl]-5-[(2-hydroxy-1-oxopropyl)amino]-2,4,6-triiodo-1,3-benzenedicarboxamide of formula (I) starting from the compound of formula (II) said process comprising: a) reacting the compound of formula (II) with a suitable protecting agent, to give a compound of formula (III)  wherein —R is a group of formula A or B  wherein R b) acylating the amino group in position 5 of the intermediate compound of formula (III), by reaction with a (S)-2-(acetyloxy)propanoyl chloride to give a compound of formula (IV)  wherein R is as defined above; and c) removing all the acyl groups present in the compound of formula (IV) under basic conditions, with prior cleavage of the cyclic protection under acidic conditions when R is a group of formula A; wherein there is no isolation step of the compound of formula (IV) before step c.