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:
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 thioeter 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 an improved process for producing naltrexone[17-(cyclopropylmethyl)-4,5α-epoxy-3,14-dihydroxy-morphinan-6-one] from noroxymorphone[4,5-α-epoxy-3,14-dihydroxy-morphinan-6-one] by alkylation with a cyclopropylmethyl halide.
摘要:
The present invention relates to a process for manufacturing N-Formyl-1-amino-3,5-dimethyladamantane, an intermediate product in the overall process of producing 1-Amino-3,5-dimethyladamantane hydrochloride (Memantine). Therein, the process comprises the following steps: (a) reacting 1,3-dimethyladamantane with an acid mixture comprising concentrated sulfuric acid and concentrated nitric acid, wherein 1 to 6 volume parts of sulfuric acid (measured in ml) are used per weight part of 1,3-dimethyladamantane (measured in g); (b) reacting the solution from step (a) with an amount of formamide varying from 1 to 5 molar equivalents per mole of deprotonated 1,3-dimethyladamantane from step (a) to obtain N-Formyl-1-amino-3,5-dimethyladamantane. In step (b), the molar ratio of total acid, i.e. the molar amount of sulfuric acid and the molar amount of nitric acid taken together versus the molar amount of formamide is at least 1.5 and that the temperature is at least 50° C. The present invention also relates to the overall process of manufacturing Memantine from 1,3-dimethyladamantane by means of hydrolyzing the intermediate NFORM.
摘要:
Method for producing nalmefene hydrochloride from naltrexone, which method is particular well adapted for large-scale industrial application, and has been found to be efficient, to give a high yield and to afford highly pure nalmefene hydrochloride salt.
摘要:
Method for producing nalmefene hydrochloride from naltrexone, which method is particular well adapted for large-scale industrial application, and has been found to be efficient, to give a high yield and to afford highly pure nalmefene hydrochloride salt.
摘要:
This patent discloses a method for resolution of 4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)-benzonitrile as a racemic or non-racemic enantiomer mixture into its isolated enantiomers, said method comprising the step of fractionally crystallizing 4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)-benzonitrile as a salt with the (+)-(S,S)- or (−)-(R,R)-enantiomer of O,O′-di-p-toluoyl-tartaric acid in a solvent system comprising 1-propanol, ethanol or acetonitrile.
摘要:
Methods for preparing Ritodrine hydrochloride are provided. Also provided is non-hygroscopic, crystalline, polymorphic Ritodrine hydrochloride of Form I.
摘要:
This patent discloses a method for resolution of 4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)-benzonitrile as a racemic or non-racemic enantiomer mixture into its isolated enantiomers, said method comprising the step of fractionally crystallizing 4-[4-(dimethylamino)-1-(4′-fluoro-phenyl)-1-hydroxybutyl]-3-(hydroxymethyl)-benzonitrile as a salt with the (+)—(S,S)— or (−)—(R,R)-enantiomer of O,O′-di-p-toluoyl-tartaric acid in a solvent system comprising 1-propanol, ethanol or acetonitrile.
摘要:
The present invention relates to an improved process for producing naltrexone[17-(cyclopropylmethyl)-4,5α-epoxy-3,14-dihydroxy-morphinan-6-one] from noroxymorphone[4,5-α-epoxy-3,14-dihydroxy-morphinan-6-one] by alkylation with a cyclopropylmethyl halide.