Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bioiberica SA
Farmhispania SA
Original Assignee
Bioiberica SA
Farmhispania SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bioiberica SA, Farmhispania SAfiledCriticalBioiberica SA
Priority to ES543210ApriorityCriticalpatent/ES8606342A1/en
Publication of ES543210A0publicationCriticalpatent/ES543210A0/en
Publication of ES8606342A1publicationCriticalpatent/ES8606342A1/en
1-Ethyl 6-fluoro 7-(1-piperazinyl) 4-oxo- 1,4-dihydro 1,8-naphthiridine 3-carboxylic acid of formula (I) is made by reaction of 1-ethyl 6-fluoro 7-(4-benzyl 1-piperazinyl) 4-oxo 1,4-dihydro 1,8-naphthiridine 3-carboxylic acid benzyl ester of formula (II) with hydrogen in an inert solvent, e.g. a lower alcohol, acetic acid or aq. HCl, in presence of Ni, Co or a noble metal, e.g. Pd, as catalyst, at normal pressure or slightly above, and at 20-50 deg.C.