| 摘要 |
<p>A process for the preparation of (S)-N,N'-bis[2-hydroxy-1-hydroxymethyl)ethyl]-5-](2-hydroxy-1-oxop ropyl)amino]-2,4,6-triiodo-1,3-benzenedicarboxamide (iopamidil) starting from 5-amino-N,N'-bis[2-hydroxy-1-(hydroxymethyl)ethyl]2,4,6,-triiodo-1 ,3- benzenedicarboxamide of formula which process comprises a) reacting the compound of the formula quoted above, with a suitable protecting agent, to give a compound of formula wherein R is a group of formula wherein R1 is a hydrogen atom, a C1-C4 straight or branched alkoxy group, R2 is hydrogen, a C1-C4 straight or branched alkoxy group and R3 is a C1-C4 straight or branched alkyl group, a trifluoromethyl of a trichlormethyl 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 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 protections of the hydroxy groups in the carboxamido substituents under acidic conditions, when R is a group of formulae A. The invention also refers to the new intermediates of formulae (III) and (IV) wherein -R is a group A. 18 claims</p> |
