| 摘要 |
<p>A 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-benzendicarboxamide of formula (l) starting from a compound of formula (II) which process comprises 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 R1 is a hydrogen atom, a C1-C4 straight or branched alkyl group or a C1-C4 straight or branched alkoxy group, R2 is hydrogen, a C1-C4 straight or branched alkyl group or a C1-C4 straight or branched alkoxy group and R3 is a C1-C4 straight or branched alkyl group, a trifuoromethyl or a trichloromethyl group; 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, without isolating the compound of formula (IV).</p> |
