Substituted piperazine-2-carboxylic acids and derivatives thereof

A compound of the formula:

• ##STR29## wherein X is C.sub.1 -C.sub.4 straight chain saturated or mono-unsaturated hydrocarbyl, R.sup.4 and Y are situated in any position in X and wherein at least one of the hydrogen atoms in X and wherein at least one of the hydrogen atoms in X can be a heavy isotope of hydrogen;
• R.sup.4 is hydrogen or alkyl, alkoxy, hydroxy, aryl, aryloxy, aralkyl, aralkoxy, aralkylamino, or morpholino wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have from 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• and Y is selected from:
• ##STR30## where R.sup.6 and R.sup.7 which may be the same or different is each hydrogen or alkyl, aryl, or aralkyl, wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo, or Y is a 6-uracil residue;
• R is hydrogen or alkyl, aryl or aralkyl wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• R.sup.1 is hydrogen or alkyl, aryl, or aralkyl wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have from 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• R.sup.2, R.sup.3 and R.sup.5 which may be the same or different is each hydrogen or alkyl, hydroxy, alkoxy, carboxy, alkyloxycarbonyl, halogeno selected from fluoro, chloro, bromo, aryl, or aryloxycarbonyl wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have 1 to 6 carbon atoms, and the aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• or a physiologically acceptable salt thereof.

A compound of the formula:

• ##STR31## wherein X is C.sub.1 -C.sub.4 straight chain saturated or mono-unsaturated hydrocarbyl, R.sup.4 and Y are situated in any position in X and wherein at least one of the hydrogen atoms in X can be a heavy isotope of hydrogen;
• R.sup.4 is hydrogen or alkyl, alkoxy, hydroxy, aryl, aryloxy, aralkyl, aralkoxy, aralkylamino, or morpholino wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have from 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• and Y is selected from:
• ##STR32## where R.sup.6 and R.sup.7, which may be the same or different, is each hydrogen or alkyl, aryl, or aralkyl, wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo, or Y is a 6-uracil residue;
• or R.sup.4 --X--Y represents --CO--R.sup.8 wherein R.sup.8 is saturated or unsaturated C.sub.1 -C.sub.6 aliphatic hydrocarbyl, phenyl or naphthyl, optionally substituted by one or more halogeno selected from fluoro, chloro and bromo, carboxy, hydroxy or C.sub.1 --C.sub.6 alkoxy;
• R is hydrogen or alkyl, aryl or aralkyl wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have 1 to 6 carbon atoms, and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• R.sup.1 is hydrogen or alkyl, aryl, or aralkyl wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have from 1 to 6 carbon atoms and the alkyl and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• R.sup.2, R.sup.3 and R.sup.5 which may be the same or different is each hydrogen or alkyl, hydroxy, alkoxy, carboxy, alkyloxycarbonyl, halogeno selected from fluoro, chloro, bromo, aryl, or aryloxycarbonyl wherein the aryl moieties are phenyl or naphthyl, the alkyl moieties have 1 to 6 carbon atoms, and aryl moieties are optionally substituted by one or more halogeno selected from fluoro, chloro and bromo;
• or a physiologically acceptable salt thereof.