摘要:
A process for the preparation of 5-amino-2,4,6-triiodoisophthalic acid dichloride by chlorination of 5-amino-2,4,6-triiodoisophthalic acid with thionyl chloride in the presence of a suitable solvent characterized in that the reaction is carried out in the presence of catalytic amounts of a tetraalkylammonium salt of formulaR.sub.1 R.sub.2 R.sub.3 R.sub.4 NX (I)wherein X is halogen, mesylate or tosylate; R.sub.1, R.sub.2, R.sub.3 and R.sub.4, the same or different, are C.sub.1 -C.sub.20 alkyl groups so that the total number of carbon atoms of the groups R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is higher than 16.The 5-amino-2,4,6-triiodoisophthalic acid dichloride obtained according to the process of the present invention is useful as intermediate in the synthesis of iodinated contrast media.
摘要翻译:通过在合适的溶剂存在下,用亚硫酰氯氯化5-氨基-2,4,6-三碘代邻苯二甲酸制备5-氨基-2,4,6-三碘代邻苯二甲酸二氯化物的方法,其特征在于反应是 在催化量的式R 1 R 2 R 3 R 4 N X(I)的四烷基铵盐的存在下进行,其中X是卤素,甲磺酸酯或甲苯磺酸酯; R 1,R 2,R 3和R 4相同或不同,为C 1 -C 20烷基,使得R 1,R 2,R 3和R 4基团的总碳原子数高于16.将5-氨基-2,4 根据本发明方法获得的6-三碘间苯二甲酰氯可用作合成碘化造影剂的中间体。
摘要:
An improvement to a process for the preparation of L-5-(2-acetoxy-propionylamino)-2,4,6-triiodo-isophthalic acid dichloride by reacting 5-amino-2,4,6-triiodo-isophthalic acid dichloride with L-2-acetoxy-propionyl-chloride, is described.
摘要:
A stereoconvergent process is described for preparing optically active alpha-arylalkanoic acids using as starting substance a diastereoisomeric mixture of ketals of formula ##STR1## in which the substituents have the meanings given in the description. The described process leads to the formation of a single enantiomer.
摘要:
An electro-optic device 200 comprising a substrate in which first and second waveguides 202, 203 are formed. The device also comprises first and second electrodes 204, 205 comprising an optically transparent conductive material and including primary portions 204a, 205a overlying the first and second waveguides 202, 203 for electrically biasing the first and second waveguides. The device is configured such that one of the first and second electrodes includes one other portion 204b, 205b arranged alongside the primary portion 204a, 205a of the other of the first and second electrodes. This arrangement improves the electro-optic efficiency of the device without the need for a buffer layer in the electrodes.
摘要:
Provided are crystalline forms of N-[4-[2-(2-amino-4,7-dihydro-4-oxo-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]-L-glutamic acid, pemetrexed diacid, and processes for the preparation thereof.
摘要:
Provided are processes for the preparation of lyophilized pharmaceutically acceptable salts of pemetrexed diacid, in particular, pemetrexed disodium salt, directly from pemetrexed diacid or salts thereof, i.e., without isolating the obtained pemetrexed salt prior to lyophilizing it.
摘要:
The present invention relates to a novel method for manufacture of sertindole comprising manufacturing 5-chloro-1-(4-fluorophenyl)-indole and converting it to sertindole wherein the method for manufacture of 5-chloro-1-(4-fluorophenyl)-indole comprises reacting 5-chloro-indole with a 4-fluorophenylhalide in the presence of a base, a chelating ligand and catalytic amounts or a copper salt comprising copper(I) or copper(II) and an anion which does not interfere in an unfavourable way with the reaction.
摘要:
A new process for the preparation and purification of 4-4′-diamino-diphenyl-sulfone (dapsone) is described. The process described is a three step process comprising a condensation reaction with the synthesis of a thioether intermediate and then steps of oxidation and reduction in suitable conditions in order to obtain a product with good yield and purity.
摘要:
The present invention relates to a process for the preparation of gabapentin and, more in particular, to a method of synthesis of 1,1-cyclohexane acetic acid monoamide, an intermediate used in the preparation of gabapentin, comprising the basic hydrolysis reaction of α,−-diaminocarbonyl-β,β-pentamethylene glutarimide.