Patent GB-920416-A (GB)
Title: Piperazino compounds
IPC: C07D295/088
Filed: 1959-04-02
Abstract: The invention comprises piperazines of the general formula (I): <FORM:0920416/IV(a)/1> and non-toxic acid addition including penicillin and quaternary ammonium salts thereof wherein R1 and R2 is phenyl, lower alkylphenyl, halophenyl, lower alkoxy-phenyl, alkylenedioxyphenyl, thienyl, furyl, pyridyl or cycloalkyl groups and when R1 and R2 are both phenyl they may be joined by a carbon to carbon bond in the 2-position and when R2 is furyl, R1 can be propyl, R3, R13, R113 and R1113 is hydrogen or a lower alkyl group, R4 is a lower alkyl, aralkyl, aryl, aralkenyl, lower alkoxy- or halo-substituted aralkyl alkenyl group, A is hydroxy or halogen, Y is a lower alkylene group, and when both R1 and R2 are phenyl, R4 and Y are not methyl and ethylene, respectively, piperazines of the general formula (II): <FORM:0920416/IV(a)/2> and acid addition salts thereof, wherein R5 is a phenyl, thienyl, pyridyl, or cyclohexyl group, R6 is a phenyl, thienyl, furyl, cyclohexyl, cyclopentyl, or lower alkyl group, R3, R13, R113, R1113 is hydrogen or a lower alkyl group.  R7 is hydrogen or an acyl or benzyl group, A is hydroxy or halogen and Y1 and Y11 are lower alkylene groups of at least 2 carbons each; a process for the preparation of compounds (I) by (a) reacting an acid derivative of the formula: <FORM:0920416/IV(a)/3> with a piperazine alkanol of the formula: <FORM:0920416/IV(a)/4> wherein R8 is lower alkyl, Z is a reactive halogen, and X is halogen, and, if required, hydrolysing the reaction product when A is halogen to form the hydroxy derivative; or (b) reacting an acid of the formula: <FORM:0920416/IV(a)/5> with a piperazine: <FORM:0920416/IV(a)/6> wherein Z is a reactive halogen; a process which comprises reacting a compound of the formula: <FORM:0920416/IV(a)/7> with 9-hydroxyfluorene-9-carboxylic acid or a lower alkyl ester thereof to form the corresponding ester wherein Z is a halogen atom R14 is a lower alkyl, aralkyl, hydroxyalkyl, acyloxyalkyl, acyloxyalkoxyalkyl, hydroxyalkoxyalkyl, alkoxyalkyl, benzyloxyalkoxyalkyl or benzyloxyalkyl group and when the lower alkyl ester is used in the reaction R14 may be acyloxyalkyl and may not be hydroxyalkyl except that the hydroxy groups on the hydroxyalkyl group are esterified or etherified to block it during the reaction and subsequently regenerated; a process for preparing compounds of the general formula II (A=OH; R7=H) either by reacting a compound of the formula: <FORM:0920416/IV(a)/8> with a compound: <FORM:0920416/IV(a)/9> wherein R9 and R10 have the same meanings as R5 and R6 respectively and R8 is a lower alkyl group and catalytically hydrogenating the compound to remove the hydrocarbon aryl group or by reacting a compound of the formula: <FORM:0920416/IV(a)/100> with a compound: <FORM:0920416/IV(a)/111> wherein Z and Z1 are reactive halogen atoms and hydrolysing the compound formed thereby. 4-Cinnamyl-piperazinoethanol is prepared from cinnamyl chloride and hydroxyethylpiperazine; 4 - beta-benzyloxyethylpiperazinoethanol is similarly prepared.  Pharmaceutical compositions comprise the compounds of the invention and a suitable pharmaceutical carrier and may be formulated as powders, tablets or capsules.  The compounds of the invention form salts with penicillin and may be used to isolate penicillin from fermentation broths and other solutions of the antibiotic.