| 摘要 |
PURPOSE: Provided are a process for obtaining sodium or potassium salts of 4-carboxy-3-hydroxy-5-mercapto-isothiazole which are compounds usable in the production of Cefotetan, and new compounds obtained thereby. CONSTITUTION: A process for obtaining 4-carboxy-3-hydroxy-5-mercapto-isothiazole salts of formula(3), wherein R1, R2, and R3 are Na or K; R1 is Na or K and R2 and R3 are H; or R1 and R2 are Na or K and R3 is H, is characterized in that the disodium or dipotassium salt of 3-hydroxy-5-mercapto-4-isothiazole carbonitrile is refluxed in an aqueous solution of sodium hydroxide or potassium hydroxide in a quantity between 3 and 6 equivalents for a time period of at least 15 hours, to give an aqueous solution containing the trisodium or respectively tripotassium salt of 4-carboxy-3-hydroxy-5-mercapto-isothiazole, and the salt is precipitated from this solution when the solution pH is corrected to a minimum value of about 8 by adding HCl.
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