- PROCESS FOR THE PREPARATION OF IOPAMIDOL
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The present invention provides a process for the preparation of a compound of Formula (II) wherein the process comprises: (i) reacting a compound of Formula (I) with pyridine and 2-acetyloxypropanoyl chloride (APC) to give a compound of Formula (II), wherein the compound of Formula (I) has the following structure.
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Paragraph 9-11
(2022/01/12)
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- MECHANOCHEMICAL SYNTHESIS OF RADIOGRAPHIC AGENTS INTERMEDIATES
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The present invention generally relates to a process using a mechanochemical approach exploiting the mechanical milling of reactants for the manufacturing of acetyl Iopamidol and, more generally, of key intermediates of radiographic contrast agents, and of the contrast agents themselves.
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Page/Page column 21; 22; 23; 24; 25; 26
(2018/06/30)
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- PROCESS FOR THE PREPARATION OF IOPAMIDOL
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The present invention discloses a process for the preparation of Iopamidol of formula (II) and comprising the following steps: a) reacting the Compound (I) wherein X is OR2 or R3, and wherein R2 and R3 are a Ci-C6 linear or branched alkyl, C3-C6 cycloalkyl, C6 aryl, optionally substituted with a group selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, t-butyl and phenyl, with the acylating agent (S)-2-(acetyloxy)propanoyl chloride in a reaction medium to provide the acetyloxy derivative of Compound (I); b) hydrolyzing the intermediate from step a) with an aqueous solution at a pH comprised from 0 to 7, by adding water or a diluted alkaline solution such as sodium hydroxide or potassium hydroxide, freeing the hydroxyls from the boron-containing protective groups, obtaining the N-(S)-2-(acetyloxy)propanoyl derivative of Compound (II); c) alkaline hydrolysis to restore the (S)-2-(hydroxy)propanoyl group and to obtain lopamidol (II) and optional recovery of the boron derivative from the solution obtained in step b). The boron-containing protective group is versatile, efficient and recyclable. A one-pot synthesis, without intermediate isolation is provided, leading to a decreasing of recovered and recycled solvents and a significant increasing in the yield, representing a significant advantage in terms of cost-effectiveness of the entire process and environmental awareness.
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Page/Page column 20-21
(2015/05/26)
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- Manufacture of a Triiodinated Contrast Agent
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A new compound, (S)-5-(2-acetoxypropanamido)-2,4,6-triiodoisophthalic acid, of formula II (S)-5-(2-acetoxypropanamido)-2,4,6-triiodoisophthalic acid. Said new compound is of use for the production of triiodinated contrast agent, especially lopamidol, with low content of acetyl and hydroxyacetyl analogs. The new compound may be formed from 5-amino-2,4,6-triiodoisophtalic acid by acylating with (S)-1-chloro-1-oxopropan-2-yl acetate. The new compound may then be converted to the respective acid dichloride by reacting with a chlorinating reagent, which is a further object of the present invention, followed by the amidation with 2-amino-1,3-propanediol and acetate hydrolysis.
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- Process For The Preparation Of Contrast Agents
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The present invention relates to a process for the preparation of 5-[(2-hydroxyacyl)amino]-2,4,6-triiodo-1,3-benzendicarboxamidic derivatives comprising the Smiles rearrangement of a suitable precursor, by contact of an aqueous solution of this latter with an anion exchanger solid phase.
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Paragraph 0063; 0064; 0070; 0071; 0072
(2013/06/04)
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- PROCESS FOR THE PREPARATION OF CONTRAST AGENTS
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The present invention relates to a process for the preparation of 5-[(2- hydroxyacyl)amino]-2,4,6-triiodo-1,3-benzendicarboxamidic derivatives comprising the Smiles rearrangement of a suitable precursor, by contact of an aqueous solution of this latter with an anion exchanger solid phase.
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Page/Page column 13; 14
(2012/02/02)
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- MANUFACTURE OF A TRIIODINATED CONTRAST AGENT
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A new compound, (S)-5-(2-acetoxypropanamido)-2,4,6-triiodoisophthalic acid, of formula II (S)-5-(2-acetoxypropanamido)-2,4,6-triiodoisophthalic acid. Said new compound is of use for the production of triiodinated contrast agent, especially lopamidol, with low content of acetyl and hydroxyacetyl analogs. The new compound may be formed from 5-amino-2,4,6-triiodoisophtalic acid by acylating with (S)-1-chloro-1-oxopropan-2-yl acetate. The new compound may then be converted to the respective acid dichloride by reacting with a chlorinating reagent, which is a further object of the present invention, followed by the amidation with 2-amino-1,3-propanediol and acetate hydrolysis.
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- PROCESS FOR THE PREPARATION OF IODINATED CONTRAST AGENT
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The present invention relies on a process for the preparation of non ionic iodinated contrast agents and, in more details, it relates to a process for the preparation of Iopamidol in high yields and with a high degree of purity. In more details, the invention discloses a process for the preparation of a compound of formula (III) comprising the 5 condensation reaction a compound of formula (II) with 2-amino-1,3-propandiol, being said reaction carried out in an aprotic dipolar solvent and in the presence of an alkaline or alkaline rare earth metal oxide or hydroxide.
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Page/Page column 11-12
(2010/07/10)
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- Process for the preparation of iopamidol and the new intermediated therein
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A process for the preparation of (S)-N,N′-bis[2-hydroxy-1-(hydroxymethyl)ethyl]-5-[(2-hydroxy-1-oxo-propyl)amino]-2,4,6-triiodo-1,3-benzendicarboxamide (iopamidol) starling from 5-amino-N,N′-bis[2-hydroxy-1-(hydroxymethyl)ethyl]-2,4,6-triiodo-1,3-benzenedicarboxamide (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 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 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, with prior cleavage of the cyclic protections of the hydroxy groups in the carboxamido substituents under acidic conditions, when R is a group of formula A carboxamido hydroxy groups under acidic conditions. The invention also refers to the new intermediates of formula (III) and (IV) wherein —R is a group A.
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- Process for the preparation of n,n-substituted 5-amino-1,3-benzenedicarboxamides
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The invention relates to a process for the preparation of a compound of formula (I), wherein R represents a 2,3-dihydroxy-1-propyl or a 1,3-dihydroxy-2-propyl radical, via direct amidation of a dialkyl ester of 5-amino-1,3-benzenedicarboxylic acid of formula (V), wherein R1 represents a straight or branched (C1-C4)-alkyl group, with at least the stoichiometric amount of an amine of formula H2NR.
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- 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
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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-benzenedicarboxamide, comprising the reaction of S-(?)-5-[[2-(acetyloxy)-1-oxopropyl]amino]-2,4,6-triiodo-1,3-benzenedicarboxylic acid dichloride (III) with 2-amino-1,3-propanediol (serinol) without a solvent, followed by hydrolysis of the acetate group.
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- PROCESS FOR THE PREPARATION OF IOPAMIDOL
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The present invention discloses a process for the preparation of pure non-ionic contrast agents. The invention also includes a method for purifying the non-ionic contrast agents.
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- Process for the manufacturing of iodinated contrast agents
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A process for the preparation of compounds of general formula (I) STR1 characterized in that the corresponding derivatives of general formula (II) STR2 are reacted with the compounds of general formula (III) STR3 wherein Z is halogen atom or a reactive residue of a sulfonic acid or a --N+ (R9)3 cation wherein R9 is a (C1 -C6) alkyl group and R1, R2, R3, R4, R5 R6 R7 and R8 are as herein defined.
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- Smiles rearrangement as a tool for the preparation of 5-[(2-hydroxyacyl)amino]-2,4,6-triiodo-1,3-benzenedicarboxamides: Main pathway and side reactions
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In the preparation of 5-[(2-hydroxyacyl)amino]-2,4,6-triiodo-1,3-benzenedicarboxamides 1a-h from 2a-h two conditions using stoichiometric amounts of base (method A - aq NaOH at 50°C; method B - MeONa in DMF at r, t.) were used. Yields are good to excellent provided that the right conditions are chosen. Primary amides 2a,b give 1a,b with method B only, whereas with method A extensive hydrolysis of the CONH2 moiety is observed. N-Methyl derivatives 2c,d afford 1c,d with either method. However, with method B long reaction times lead to the formation of large amounts of benzoxazinones, 4c,d. Under the same conditions, the pattern of side products which are formed from N-(hydroxyalkyl)phenoxyacetamides 2e-g is further complicated by: i) intramolecular cyclizations leading to bicyclic (7f,g) and tricyclic structures (5) ii) N-deacylation; iii) double Smiles rearrangement reactions.
- Anelli, Pier Lucio,Brocchetta, Marino,Calabi, Luisella,Secchi, Carlo,Uggeri, Fulvio,Verona, Sandra
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p. 11919 - 11928
(2007/10/03)
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- Process for the purifying of iopamidol
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A process for purifying Iopamidol which uses a butanol as solvent is described. Iopamidol is obtained with high yields, also starting from aqueous solutions of the same and has characteristics in accordance with those required by pharmacopoeia.
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- Process for the purification and crystallisation of iopamidol
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The present invention describes a process for the purification and crystallisation of lopamidol, wherein 1-propanol, or 2-propanol, is added to an aqueous solution of lopamidol followed, if necessary, by azeotropic distillation to reduce the quantity of water in relation to the quantity of propanol, and thereby ensure an high yield. The aqueous solution can be prepared either by the dissolution of crude lopamidol in water or directly from the reaction in which the lopamidol is formed. The present invention presents advantages for the routine production of lopamidol since the crystallisation is straighfforward to perform, can be easily controlled and is reproducible at an industrial scale.
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