Patent IE-51012-B1 (IE)
Title: Benzoxazolyl dihydropyridazinone derivatives
IPC: C07D237/04
Filed: 1981-02-20
Abstract: 1. Claims for the Contracting States : BE, CH, DE, FR, GB, IT, LI, LU, NL Benzoxazoles of general formula  see diagramm : EP0034743,P9,F2  in which R1 represents a hydrogen atom ; a straight or branched alkyl group with 1 to 7 carbon atoms which can be substituted by an alkoxy group with 1 to 3 carbon atoms ; a cycloalkyl group with 3 to 7 carbon atoms ; an alkyl group with 1 to 3 carbon atoms substituted by a phenyl group which can be substituted by one or two alkoxy groups with 1 to 3 carbon atoms ; or a phenyl group which can be substituted by an alkyl or alkoxy group each with 1 to 3 carbon atoms, by a trifluormethyl, nitro or cyano group or by a fluorine, chlorine or bromine atom ; and in addition one of the mono-substituted phenyl groups mentioned above can be substituted by one or two alkyl groups with 1 to 3 carbon atoms or by an alkoxy group with 1 to 3 carbon atoms or by a fluorine, chlorine or bromine atom ; and R2 represents a hydrogen atom or an alkyl group with 1 to 3 carbon atoms ; and their optically active antipodes as well as their physiologically compatible acid addition salts with inorganic or organic acids. 1. Claims for the Contracting State : AT Process for producing benzoxazoles of general formula  see diagramm : EP0034743,P10,F4  in which R1 represents a hydrogen atom ; a straight or branched alkyl group with 1 to 7 carbon atoms which can be substituted by an alkoxy group with 1 to 3 carbon atoms ; a cycloalkyl group with 3 to 7 carbon atoms ; an alkyl group with 1 to 3 carbon atoms substituted by a phenyl group which can be substituted by one or two alkoxy groups with 1 to 3 carbon atoms ; or a phenyl group which can be substituted by an alkyl or alkoxy group each with 1 to 3 carbon atoms, by a trifluormethyl, nitro or cyano group or by a fluorine, chlorine or bromine atom ; and additionally one of the mono-substituted phenyl groups mentioned above can be substituted by one or two alkyl groups with 1 to 3 carbon atoms or by an alkoxy group with 1 to 3 carbon atoms or by a fluorine, chlorine or bromine atom ; and R2 represents a hydrogen atom or an alkyl group with 1 to 3 carbon atoms ; and their optically active antipodes as well as their physiologically compatible acid addition salts with inorganic or organic acids characterised in that  see diagramm : EP0034743,P11,F1  in which R1 and R2 are as defined in the introduction, X represents a mercapto, alkylmercapto, arylmercapto or aralkylmercapto group, and Y represents a hydrogen atom or an acyl radical, is cyclised ; or b) a carboxylic acid of general formula see diagramm : EP0034743,P11,F3  in which R1 and R2 are as defined in the introduction, or its amides, esters, thioester or halides, is reacted with hydrazine ; and if desired a compound of general formula I, in which R1 represents a hydrogen atom, obtained according to processes a) or b) is subsequently converted by means of alkylation into a corresponding compound of general formula I, in which R1 is defined as in the introduction with the exception of the hydrogen atom and the phenyl radicals mentioned in the introduction, and/or a racemate obtained, of general formula I, is separated by means of racemate separation into its optically active antipodes, and/or a compound obtained, of general formula I, is converted into its physiologically compatible acid addition salts with inorganic or organic acids.