- Oxiracetam preparation method
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An oxiracetam preparation method comprises the following steps: (a) azidation reaction of 4-chloro-3-hydroxybutyrate as a starting material and an azidation reagent to obtain an give intermediate I; (2) reduction reaction of the intermediate I to obtain an intermediate II; (2) condensation reaction of the intermediate II and a halogenated acetic acid ester to obtain an intermediate III; (3) ring closing reaction of the intermediate III to obtain an intermediate IV; and (4) aminolysis reaction of the intermediate IV to obtain desired product oxiracetam. The desired product oxiracetam with an ideal yield of at least more than 38% can be obtained, and a new oxiracetam synthetic route is opened up.
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Paragraph 0078; 0079; 0092; 0093
(2016/10/27)
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- Process for the production of 4-hydroxy-2-oxopyrrolidin-1-yl-acetamide
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Process for the production of 4-hydroxy-2-oxoyrrolidin-1-yl-acetamide, a cerebrally active pharmaceutical agent. A 4-halo-3-alkoxy-butenoic acid ester is reacted with glycine to new intermediate products of the formula: STR1 There is further by acid hydrolysis of the alkoxy group, subsequent hydrogenation, esterification of the carboxyl function and finally conversion to the end product by reaction with ammonia.
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- Process for the production of 4-hydroxy-2-oxo-pyrrolidin-1-yl acetamide
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Process for the production of 4-hydroxy-2-oxo-pyrrolidin-1-yl acetamide. A 4-(C1 -C2)-alkoxy-3-pyrrolin-2-on-1-yl-acetic acid (C1 -C4)-alkyl ester of the formula: STR1 wherein R1 is alkyl having 1 or 2 C atoms and R2 is alkyl having 1 to 4 C atoms, is reacted with either trichloromethylsilane in the presence of an alkali iodide or in an acid anhydrous medium to a 2,4-dioxo-pyrrolidin-1-yl-acetic acid (C1 -C4)-alkyl ester. The latter is optionally isolated and then hydrogenated with sodium borohydride to a 4-hydroxy-2-oxo-pyrrolidin-1-yl-acetic acid (C1 -C4)-alkyl ester. Finally, the 4-hydroxy-2-oxo-pyrrolidin-1-yl-acetic acid (C1 -C4)-alkyl ester is converted by amidation with ammonia to the desired end product.
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- Preparation of pyrrolidine and pyrrolidin-2-one derivatives
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Preparation of compounds of the formula: STR1 wherein n is 1, 2 or 3, R1 and R2, which may be the same or different, are hydrogen or alkyl containing 1 to 3 carbon atoms and the asterisk indicates the center of asymmetry of the molecule, and compounds of the formula STR2 wherein R" is a saturated or unsaturated aliphatic hydrocarbon containing 1 to 6 carbon atoms, R3 is hydrogen or acyl containing 1 to 7 carbon atoms and the asterisk indicates the center of asymmetry of the molecule. The compounds produced by the present invention improve learning memory and display a protecting effect against the E.E.G. consequence of an overdose of barbiturates and against the reduced performance following brain damage (e.g. cerebral edema).
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