R¹ represents an A-B-D group wherein

(I) A denotes

(a) a C_1-6-alkyl group substituted by a phenyl group, where the C_1-6-alkyl group may be substituted by one to twelve fluorine atoms and the phenyl ring may be substituted by the groups R¹⁰ to R¹⁴ and

i. R¹⁰ denotes

a. a fluorine, chlorine, bromine or iodine atom,

b. a C_1-4-alkyl, hydroxy, or C_1-4-alkyloxy group,

c. a nitro, amino, C_1-3-alkylamino, di-(C_1-3-alkyl)amino, cyano-C_1-3-alkylamino, [N-(cyano-C_1-3-alkyl)-N—C_1-3-alkyl-amino], C_1-3-alkyloxy-carbonyl-C_1-3-alkylamino, pyrrolidin-1-yl, piperidin-1-yl, morpholin-4-yl, piperazin-1-yl, 4-(C_1-3-alkyl)-piperazin-1-yl, C_1-3-alkyl-carbonylamino, arylcarbonylamino, aryl-C_1-3-alkyl-carbonylamino, C_1-3-alkyloxy-carbonylamino, aminocarbonylamino, C_1-3-alkyl-amino-carbonylamino, di-(C_1-3-alkyl)aminocarbonylamino, C_1-3-alkyl-sulphonylamino, bis-(C_1-3-alkylsulphonyl)-amino, aminosulphonylamino, C_1-3-alkylamino-sulphonylamino, di-(C_1-3-alkyl)amino-sulphonylamino, morpholin-4-yl-sulphonylamino, (C_1-3-alkylamino)thiocarbonylamino, (C_1-3-alkyloxy-carbonylamino)carbonylamino, arylsulphonylamino or aryl-C_1-3-alkyl-sulphonylamino group,

d. an N—(C_1-3-alkyl)-C_1-3-alkyl-carbonylamino, N—(C_1-3-alkyl)-arylcarbonylamino, N—(C_1-3-alkyl)-aryl-C_1-3-alkyl-carbonylamino, N—(C_1-3-alkyl)-C_1-3-alkyloxy-carbonylamino, N-(aminocarbonyl)-C_1-3-alkylamino, N—(C_1-3-alkyl-aminocarbonyl)-C_1-3-alkylamino, N-[di-(C_1-3-alkyl)aminocarbonyl]-C_1-3-alkylamino, N—(C_1-3-alkyl)-C_1-3-alkyl-sulphonylamino, N—(C_1-3-alkyl)-arylsulphonylamino, or N—(C_1-3-alkyl)-aryl-C_1-3-alkyl-sulphonylamino group,

e. a 2-oxo-imidazolidin-1-yl, 2,4-dioxo-imidazolidin-1-yl or 2,5-dioxo-imidazolidin-1-yl group wherein the nitrogen atom in the 3 position may in each case be substituted by a methyl or ethyl group,

f. a cyano, carboxy, C_1-4-alkyloxy-carbonyl, aminocarbonyl, C_1-3-alkyl-aminocarbonyl, di-(C_1-3-alkyl)-aminocarbonyl, pyrrolidin-1-yl-carbonyl, piperidin-1-yl-carbonyl, morpholin-4-yl-carbonyl, piperazin-1-yl-carbonyl or 4-(C_1-3-alkyl)-piperazin-1-yl-carbonyl group,

g. a C_1-3-alkyl-carbonyl or an arylcarbonyl group,

h. a carboxy-C_1-3-alkyl, C_1-3-alkyloxy-carbonyl-C_1-3-alkyl, cyano-C_1-3-alkyl, aminocarbonyl-C_1-3-alkyl, C_1-3-alkyl-aminocarbonyl-C_1-3-alkyl, di-(C_1-3-alkyl)-aminocarbonyl-C_1-3-alkyl, pyrrolidin-1-yl-carbonyl-C_1-3-alkyl, piperidin-1-yl-carbonyl-C_1-3-alkyl, morpholin-4-yl-carbonyl-C_1-3-alkyl, piperazin-1-yl-carbonyl-C_1-3-alkyl or 4-(C_1-3-alkyl)-piperazin-1-yl-carbonyl-C_1-3-alkyl group,

i. a carboxy-C_1-3alkyloxy, C_1-3-alkyloxy-carbonyl-C_1-3-alkyloxy, cyano-C_1-3alkyloxy, aminocarbonyl-C_1-3alkyloxy, C_1-3-alkyl-aminocarbonyl-C_1-3-alkyloxy, di-(C_1-3-alkyl)-aminocarbonyl-C_1-3-alkyloxy, pyrrolidin-1-yl-carbonyl-C_1-3-alkyl-oxy, piperidin-1-yl-carbonyl-C_1-3-alkyloxy, morpholin-4-yl-carbonyl-C_1-3-alkyl-oxy, piperazin-1-yl-carbonyl-C_1-3alkyloxy or 4-(C_1-3-alkyl)-piperazin-1-yl-carbonyl-C_1-3alkyloxy group,

j. a hydroxy-C_1-3-alkyl, C_1-3alkyloxy-C_1-3-alkyl, amino-C_1-3-alkyl, C_1-3-alkylamino-C_1-3-alkyl, di-(C_1-3-alkyl)-amino-C_1-3-alkyl, pyrrolidin-1-yl-C_1-3-alkyl, piperidin-1-yl-C_1-3-alkyl, morpholin-4-yl-C_1-3-alkyl, piperazin-1-yl-C_1-3-alkyl, 4-(C_1-3-alkyl)-piperazin-1-yl-C_1-3-alkyl group,

k. a hydroxy-C_1-3alkyloxy, C_1-3alkyloxy-C_1-3-alkyloxy, C_1-3-alkylsulphanyl-C_1-3alkyloxy, C_1-3-alkylsulphinyl-C_1-3-alkyloxy, C_1-3-alkylsulphonyl-C_1-3-alkyloxy, amino-C_1-3-alkyloxy, C_1-3-alkylamino-C_1-3-alkyloxy, di-(C_1-3-alkyl)-amino-C_1-3-alkyloxy, pyrrolidin-1-yl-C_1-3-alkyloxy, piperidin-1-yl-C_1-3alkyloxy, morpholin-4-yl-C_1-3-alkyloxy, piperazin-1-yl-C_1-3-alkyloxy, 4-(C_1-3-alkyl)-piperazin-1-yl-C_1-3-alkyloxy group,

l. a mercapto, C_1-3-alkylsulphanyl, C_1-3-alkysulphinyl, arylsulphinyl, C_1-3-alkylsulphonyl, arylsulphonyl, C_1-3-alkylsulphonyloxy, arylsulphonyloxy, trifluoromethylsulphanyl, trifluoromethylsulphinyl or trifluoromethylsulphonyl group,

m. a sulpho, aminosulphonyl, C_1-3-alkyl-aminosulphonyl, di-(C_1-3-alkyl)-aminosulphonyl, pyrrolidin-1-yl-sulphonyl, piperidin-1-yl-sulphonyl, morpholin-4-yl-sulphonyl, piperazin-1-yl-sulphonyl or 4-(C_1-3-alkyl)-piperazin-1-yl-sulphonyl group,

n. a methyl or methoxy group substituted by 1 to 3 fluorine atoms,

o. an ethyl or ethoxy group substituted by 1 to 5 fluorine atoms,

p. a C_2-4-alkenyl or C_2-4-alkynyl group,

q. a C_3-4-alkenyloxy or C_3-4-alkynyloxy group,

r. a C_3-6-cycloalkyl or C_3-6-cycloalkyloxy group,

s. a C_3-6-cycloalkyl-C_1-3-alkyl or C_3-6-cycloalkyl-C_1-3-alkyloxy group or

t. an aryl, aryloxy, aryl-C_1-3-alkyl or aryl-C_1-3-alkyloxy group,

ii. R¹¹ and R¹², which may be identical or different, in each case denote a fluorine, chlorine, bromine or iodine atom, a C_1-3-alkyl, trifluoromethyl, hydroxy or C_1-3-alkyloxy group or a cyano group, or

iii. R¹¹ together with R¹², if they are bound to adjacent carbon atoms, also denote a methylenedioxy, difluoromethylenedioxy, straight-chain C_3-5-alkylene or —CH═CH—CH═CH— group, while the —CH═CH—CH═CH— group may be substituted by a fluorine, chlorine or bromine atom, by a methyl, trifluoromethyl, cyano, aminocarbonyl, aminosulphonyl, methylsulphonyl, methylsulphonylamino, methoxy, difluoromethoxy or trifluoromethoxy group, and

iv. R¹³ and R¹⁴, which may be identical or different, in each case represent a fluorine, chlorine or bromine atom, a trifluoromethyl, C_1-3-alkyl or C_1-3-alkyloxy group,

(b) a phenyl group which may be substituted by the groups R¹⁰ to R¹⁴, where R¹⁰ to R¹⁴ are as hereinbefore defined in this claim,

(c) a phenyl-C_2-3-alkenyl group wherein the phenyl moiety may be substituted by the groups R¹⁰ to R¹⁴, where R¹⁰ to R¹⁴ are as hereinbefore defined in this claim, and the alkenyl group may be substituted by one to four fluorine atoms or methyl groups, while the substituents may be identical or different,

(d) a phenyl-C_2-3-alkynyl group wherein the phenyl moiety may be substituted by the groups R¹⁰ to R¹⁴, where R¹⁰ to R¹⁴ are as hereinbefore defined in this claim,

(e) a heteroaryl-C_1-6-alkyl group, while the C_1-6-alkyl group may be substituted by one to twelve fluorine atoms,

(f) a heteroaryl group,

(g) a heteroaryl-C_2-3-alkenyl group, while the alkenyl group may be substituted by one to four fluorine atoms or methyl groups, while the substituents may be identical or different, or

(h) a heteroaryl-C_2-3-alkynyl group and

(II) B denotes

(a) an E-G group, wherein E is linked to the group A and

1. E denotes

a. an oxygen or sulphur atom,

b. an —NR_a— group wherein R_a denotes a hydrogen atom, a C_1-6-alkyl, C_3-6-alkenyl, C_3-6-alkynyl, C_3-7-cycloalkyl, phenyl, phenylmethyl, heteroaryl, heteroarylmethyl, amino, C_1-6-alkylamino, di-(C_1-6-alkyl)amino, hydroxy, C_1-6-alkyloxy group, while the above-mentioned phenyl rings may each be substituted by the groups R¹⁰ to R¹¹, while R¹⁰ to R¹¹ are as hereinbefore defined in this claim,

c. an —NR_a—NR_a— group wherein R_a is as hereinbefore defined in this claim and the two groups R_a may be identical or different,

d. an —NH—NH— group wherein the two hydrogen atoms are replaced by a straight-chain C_3-5-alkylene bridge,

e. an —O—NR_a— group wherein R_a is as hereinbefore defined in this claim and the oxygen atom is linked to the group A and the nitrogen atom is linked to the group G,

f. a —O—CR_bR_c— group wherein the oxygen atom is linked to the group A and the carbon atom is linked to the group G and wherein R_b and R_c, which may be identical or different, denote a hydrogen or fluorine atom, a C_1-6-alkyl, C_3-7-cycloalkyl, phenyl, phenylmethyl, while the phenyl rings may each be substituted by the groups R¹⁰ to R¹⁴, while R¹⁰ to R¹⁴ are as hereinbefore defined in this claim, or a heteroaryl or heteroaryl-methyl group or R_b and R_c together denote a straight-chain C_2-6-alkylene group,

g. a —S—CR_bR_c— group wherein the sulphur atom is linked to the group A and the carbon atom is linked to the group G and R_b and R_c, which may be identical or different, are as hereinbefore defined in this claim,

h. a —SO—CR_bR_c— group wherein the sulphur atom is linked to the group A and the carbon atom is linked to the group G and R_b and R_c, which may be identical or different, are as hereinbefore defined in this claim,

i. a —SO₂—CR_bR_c— group wherein the sulphur atom is linked to the group A and the carbon atom is linked to the group G and R_b and R_c, which may be identical or different, are as hereinbefore defined in this claim,

j. or a —NR_a—CR_bR_c— group wherein the nitrogen atom is linked to the group A and the carbon atom is linked to the group G and R_a, R_b and R_c, which may be identical or different, are as hereinbefore defined in this claim, and

2. G denotes

a. a carbonyl or thiocarbonyl group,

b. a methylene group substituted by an imino group wherein the nitrogen atom may be substituted by a C_1-6-alkyl, C_3-6-alkenyl, C_3-6-alkynyl, C_3-7-cycloalkyl, phenyl, phenylmethyl, heteroaryl, heteroarylmethyl, amino, C_1-6-alkylamino, di-(C_1-6-alkyl)amino, pyrrolidin-1-yl, piperidin-1-yl, morpholin-4-yl, C_1-6-alkyl-carbonylamino, phenylcarbonylamino, C_1-6-alkyloxy-carbonylamino, C_1-6-alkylsulphonylamino, phenylsulphonylamino, hydroxyl, C_1-6-alkyloxy, cyano or nitro group, while the above-mentioned phenyl groups may be substituted by the groups R¹⁰ to R¹⁴, where R¹⁰ to R¹⁴ are as hereinbefore defined in this claim,

c. a 1,1-ethenylene group wherein the carbon atom in the exo position may be substituted by one or two chlorine or fluorine atoms or one or two C_1-6-alkyl, C_1-6-perfluoroalkyl, C_3-6-alkenyl, C_3-6-alkynyl, C_3-7-cycloalkyl, phenyl, phenylmethyl, heteroaryl, heteroarylmethyl, C_1-6-alkyl-carbonyl, C_3-7-cycloalkyl-carbonyl, phenylcarbonyl, heteroarylcarbonyl, carboxy, C_1-6-alkyloxy-carbonyl, aminocarbonyl, C_1-6-alkylaminocarbonyl, di-(C_1-6-alkyl)aminocarbonyl, pyrrolidin-1-ylcarbonyl, piperidin-1-ylcarbonyl, morpholin-4-ylcarbonyl, phenylaminocarbonyl, heteroarylaminocarbonyl, C_1-6-alkylsulphinyl, C_3-7-cycloalkylsulphinyl, phenylsulphinyl, heteroarylsulphinyl, C_1-6-alkylsulphonyl, C_3-7-cycloalkylsulphonyl, phenylsulphonyl, heteroarylsulphonyl, cyano or nitro groups, while the substituents may be identical or different and the above-mentioned phenyl groups may be substituted by the groups R¹⁰ to R¹⁴, while R¹⁰ to R¹⁴ are as hereinbefore defined in this claim,

d. or represent a sulphinyl or sulphonyl group,

(III) or A together with B denotes a 1,2,3,4-tetrahydroquinolinylcarbonyl, 1,2,3,4-tetrahydroisoquinolinylcarbonyl, 2,3-dihydroindolylcarbonyl or 2,3-dihydroisoindolylcarbonyl group wherein the benzo groups may in each case be substituted by the groups R¹⁰ to R¹³, while R¹⁰ to R¹³ are as hereinbefore defined in this claim and one or two carbon atoms of the benzo group may be replaced by nitrogen atoms and the alkylene moieties of the above-mentioned groups may in each case be substituted by one or two fluorine atoms, one or two methyl groups or an oxo group, while the substituents may be identical or different, and

(IV) D denotes

(a) a C_1-6-alkylene group which may be substituted by one to twelve fluorine atoms,

(b) a C_2-3-alkenylene group which may be substituted by one to four fluorine atoms or methyl groups,

(c) or a propynylene group,

R² denotes

(I) a hydrogen atom,

(II) a C_1-6-alkyl group,

(III) a C_2-4-alkenyl group,

(IV) a C_3-4-alkynyl group,

(V) a C_3-6-cycloalkyl group,

(VI) a C_3-6-cycloalkyl-C_1-3-alkyl group,

(VII) a tetrahydrofuran-3-yl, tetrahydropyran-3-yl, tetrahydropyran-4-yl, tetrahydrofuranylmethyl or tetrahydropyranylmethyl group,

(VIII) an aryl group,

(IX) an aryl-C_1-4-alkyl group,

(X) an aryl-C_2-3-alkenyl group,

(XI) an arylcarbonyl-C_1-2-alkyl group,

(XII) a heteroaryl-C_1-3-alkyl group,

(XIII) a furanylcarbonylmethyl, thienylcarbonylmethyl, thiazolylcarbonylmethyl or pyridylcarbonylmethyl group,

(XIV) a C_1-4-alkyl-carbonyl-C_1-2-alkyl group,

(XVI) a C_3-6-cycloalkyl-carbonyl-C_1-2-alkyl group,

(XVII) an aryl-G-C_1-3-alkyl group, while G denotes an oxygen or sulphur atom, an imino, C_1-3-alkylimino, sulphinyl or sulphonyl group,

(XVIII) a C_1-4-alkyl group substituted by a group R_d, wherein R_d denotes a cyano, carboxy, C_1-3-alkyloxy-carbonyl, aminocarbonyl, C_1-3-alkylamino-carbonyl, di-(C_1-3-alkyl)-amino-carbonyl, pyrrolidin-1-ylcarbonyl, piperidin-1-ylcarbonyl, morpholin-4-ylcarbonyl, piperazin-1-ylcarbonyl, 4-methylpiperazin-1-ylcarbonyl or 4-ethylpiperazin-1-ylcarbonyl group, or

(XIX) a C_2-4-alkyl group substituted by a group R_e, where R_e denotes a hydroxy, C_1-3-alkyloxy, amino, C_1-3-alkylamino, di-(C_1-3-alkyl)-amino, pyrrolidin-1-yl, piperidin-1-yl, morpholin-4-yl, piperazin-1-yl, 4-methyl-piperazin-1-yl or 4-ethyl-piperazin-1-yl group and is isolated from the cyclic nitrogen atom in the 3 position of the xanthine structure by at least two carbon atoms,

R³ denotes

(I) a C_3-8-alkyl group,

(II) a C_1-3-alkyl group substituted by a group R_f, where R_f denotes a C_3-7-cycloalkyl group optionally substituted by one or two C_1-3-alkyl groups or a C_5-7-cycloalkenyl group optionally substituted by one or two C_1-3-alkyl groups,

(III) a C_3-8-alkenyl group,

(IV) a C_3-6-alkenyl group substituted by a fluorine, chlorine or bromine atom or a trifluoromethyl group,

(VI) a C_3-8-alkynyl group,

(VII) an aryl group or

(VIII) an aryl-C_2-4-alkenyl group,

R⁴ denotes

(I) an azetidin-1-yl or pyrrolidin-1-yl group which is substituted in the 3 position by an amino, C_1-3-alkylamino or a di-(C_1-3-alkyl)amino group and may additionally be substituted by one or two C_1-3-alkyl groups,

(II) a piperidin-1-yl or hexahydroazepin-1-yl group which is substituted in the 3 position or in the 4 position by an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)amino group and may additionally be substituted by one or two C_1-3-alkyl groups,

(III) a 3-amino-piperidin-1-yl group wherein the piperidin-1-yl-moiety is additionally substituted by an aminocarbonyl, C_1-2-alkyl-aminocarbonyl, di-(C_1-2-alkyl)aminocarbonyl, pyrrolidin-1-yl-carbonyl, (2-cyano-pyrrolidin-1-yl)carbonyl, thiazolidin-3-yl-carbonyl, (4-cyano-thiazolidin-3-yl)carbonyl, piperidin-1-ylcarbonyl or morpholin-4-ylcarbonyl group,

(IV) a 3-amino-piperidin-1-yl group wherein the piperidin-1-yl-moiety in the 4 position or in the 5 position is additionally substituted by a hydroxy or methoxy group,

(V) a 3-amino-piperidin-1-yl group wherein the methylene group in the 2 position or in the 6 position is replaced by a carbonyl group,

(VI) a piperidin-1-yl or hexahydroazepin-1-yl group substituted in the 3 position by an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)-amino group, wherein in each case two hydrogen atoms on the carbon skeleton of the piperidin-1-yl or hexahydroazepin-1-yl- group are replaced by a straight-chain alkylene bridge, this bridge containing 2 to 5 carbon atoms if the two hydrogen atoms are located on the same carbon atom, or 1 to 4 carbon atoms if the hydrogen atoms are located on adjacent carbon atoms, or 1 to 4 carbon atoms if the hydrogen atoms are located on carbon atoms separated by one atom, or 1 to 3 carbon atoms if the two hydrogen atoms are located on carbon atoms separated by two atoms,

(VII) an azetidin-1-yl, pyrrolidin-1-yl, piperidin-1-yl or hexahydroazepin-1-yl group which is substituted by an amino-C_1-3-alkyl, C_1-3-alkylamino-C_1-3-alkyl or a di-(C_1-3-alkyl)amino-C_1-3-alkyl group,

(VIII) a piperazin-1-yl or [1,4]diazepan-1-yl group optionally substituted on the carbon skeleton by one or two C_1-3-alkyl groups, while R⁴ cannot represent a piperazin-1-yl or [1,4]diazepan-1-yl group optionally substituted on the carbon skeleton by one or two C_1-3-alkyl groups in those compounds wherein

(a) the group E denotes an oxygen atom and the group G denotes a carbonyl group,

(b) the group E denotes an oxygen atom and the group G denotes a sulphonyl group,

(c) the group E denotes an —NR_a— group and the group G denotes a carbonyl group wherein R_a is as hereinbefore defined in this claim,

(d) the group E denotes an —NR_a— group wherein R_a is as hereinbefore defined in this claim, and

(e) the group G denotes a sulphonyl group or the group A denotes a phenyl or heteroaryl group optionally substituted by one of the above-mentioned groups and the group E denotes an oxygen atom and the group G denotes an ethenylene group,

(IX) a 3-imino-piperazin-1-yl, 3-imino-[1,4]diazepan-1-yl or 5-imino-[1,4]diazepan-1-yl group optionally substituted on the carbon skeleton by one or two C_1-3-alkyl groups,

(X) a [1,4]diazepan-1-yl group optionally substituted by one or two C_1-3-alkyl groups which is substituted in the 6 position by an amino group,

(XV) a C_3-7-cycloalkylamino group wherein the cycloalkyl moiety is substituted by an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)-amino group, while the two nitrogen atoms on the cycloalkyl moiety are separated from one another by at least two carbon atoms,

(XVI) an N—(C_3-7-cycloalkyl)-N—(C_1-3-alkyl)-amino group wherein the cycloalkyl moiety is substituted by an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)-amino group, while the two nitrogen atoms on the cycloalkyl moiety are separated from one another by at least two carbon atoms,

(XVII) a C_3-7-cycloalkylamino group wherein the cycloalkyl moiety is substituted by an amino-C_1-3-alkyl, C_1-3-alkylamino-C_1-3-alkyl or a di-(C_1-3-alkyl)amino-C_1-3-alkyl group,

(XVIII) an N—(C_3-7-cycloalkyl)-N—(C_1-3-alkyl)-amino group wherein the cycloalkyl moiety is substituted by an amino-C_1-3-alkyl, C_1-3-alkylamino-C_1-3-alkyl or a di-(C_1-3-alkyl)amino-C_1-3-alkyl group,

(XIX) a C_3-7-cycloalkyl-C_1-3-alkyl-amino group wherein the cycloalkyl moiety is substituted by an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)-amino group,

(XX) an N—(C_3-7-cycloalkyl-C_1-2-alkyl)-N—(C_1-2-alkyl)-amino group wherein the cycloalkyl moiety is substituted by an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)-amino group,

(XXI) a C_3-7-cycloalkyl-C_1-2-alkyl-amino group wherein the cycloalkyl moiety is substituted by an amino-C_1-3-alkyl, C_1-3-alkylamino-C_1-3-alkyl or a di-(C_1-3-alkyl)amino-C_1-3-alkyl group,

(XXII) an N—(C_3-7-cycloalkyl-C_1-2-alkyl)-N—(C_1-3-alkyl)-amino group wherein the cycloalkyl moiety is substituted by an amino-C_1-3-alkyl, C_1-3-alkylamino-C_1-3-alkyl or a di-(C_1-3-alkyl)amino-C_1-3-alkyl group,

(XXIII) a R¹⁹-C_2-4-alkylamino group wherein R¹⁹ is separated from the nitrogen atom of the C_2-4-alkylamino moiety by at least two carbon atoms and R¹⁹ denotes an amino, C_1-3-alkylamino or di-(C_1-3-alkyl)-amino group,

(XXIV) an R¹⁹—C_2-4-alkylamino group wherein the nitrogen atom of the C_2-4-alkylamino moiety is substituted by a C_1-3-alkyl group and R¹⁹ is separated from the nitrogen atom of the C_2-4-alkylamino moiety by at least two carbon atoms, while R¹⁹ is as hereinbefore defined in this claim,

(XXV) an amino group substituted by the group R²⁰ wherein R²⁰ denotes an azetidin-3-yl, azetidin-2-ylmethyl, azetidin-3-ylmethyl, pyrrolidin-3-yl, pyrrolidin-2-ylmethyl, pyrrolidin-3-ylmethyl, piperidin-3-yl, piperidin-4-yl, piperidin-2-ylmethyl, piperidin-3-ylmethyl or piperidin-4-ylmethyl group, while the groups mentioned for R²⁰ may in each case be substituted by one or two C_1-3-alkyl groups, or

(XXVI) an amino group substituted by the group R²⁰ and a C_1-3-alkyl group wherein R²⁰ is as hereinbefore defined in this claim, while the groups mentioned for R²⁰ may in each case be substituted by one or two C_1-3-alkyl groups,

while by the aryl groups mentioned in the definition of the above groups are meant phenyl or naphthyl groups, which may be mono- or disubstituted by R_h independently of one another, where the substituents are identical or different and R_h denotes a fluorine, chlorine, bromine or iodine atom, a trifluoromethyl, cyano, nitro, amino, aminocarbonyl, aminosulphonyl, methylsulphonyl, acetylamino, methylsulphonylamino, C_1-4-alkyl, C_1-3-alkyl-carbonyl, cyclopropyl, ethenyl, ethynyl, hydroxy, C_1-4-alkyloxy, C_1-4-alkoxy-carbonyl, methylsulphinyl, phenylsulphinyl, methylsulphonyl, phenylsulphonyl, difluoromethoxy or trifluoromethoxy group,

by the heteroaryl groups mentioned in the definitions of the above-mentioned groups are meant a pyrrolyl, furanyl, thienyl, pyridyl, indolyl, benzofuranyl, benzothiophenyl, quinolinyl or isoquinolinyl group,

or a pyrrolyl, furanyl, thienyl or pyridyl group wherein one or two methyne groups are replaced by nitrogen atoms,

or an indolyl, benzofuranyl, benzothiophenyl, quinolinyl or isoquinolinyl group wherein one to three methyne groups are replaced by nitrogen atoms,

or a 1,2-dihydro-2-oxo-pyridinyl, 1,4-dihydro-4-oxo-pyridinyl, 2,3-dihydro-3-oxo-pyridazinyl, 1,2,3,6-tetrahydro-3,6-dioxo-pyridazinyl, 1,2-dihydro-2-oxo-pyrimidinyl, 3,4-dihydro-4-oxo-pyrimidinyl, 1,2,3,4-tetrahydro-2,4-dioxo-pyrimidinyl, 1,2-dihydro-2-oxo-pyrazinyl, 1,2,3,4-tetrahydro-2,3-dioxo-pyrazinyl, 2,3-dihydro-2-oxo-indolyl, 2,3-dihydrobenzofuranyl, 2,3-dihydro-2-oxo-1H-benzimidazolyl, 2,3-dihydro-2-oxo-benzoxazolyl, 1,2-dihydro-2-oxo-quinolinyl, 1,4-dihydro-4-oxo-quinolinyl, 1 ,2-dihydro-1-oxo-isoquinolinyl, 1,4-dihydro-4-oxo-cinnolinyl, 1,2-dihydro-2-oxo-quinazolinyl, 3,4-dihydro-4-oxo-quinazolinyl, 1,2,3,4-tetrahydro-2,4-dioxo-quinazolinyl, 1,2-dihydro-2-oxoquinoxalinyl, 1,2,3,4-tetrahydro-2,3-dioxo-quinoxalinyl, 1,2-dihydro-1-oxo-phthalazinyl, 1,2,3,4-tetrahydro-1,4-dioxo-phthalazinyl, chromanyl, cumarinyl, 2,3-dihydro-benzo[1,4]dioxinyl or 3,4-dihydro-3-oxo-2H-benzo[1,4]oxazinyl group,

and the above-mentioned heteroaryl groups may be mono- or disubstituted by R_h, while the substituents may be identical or different and R_h is as hereinbefore defined in this claim,

and, unless otherwise stated, the above-mentioned alkyl, alkenyl and alkynyl groups may be straight-chain or branched,

the tautomers, the enantiomers, the diastereomers, the mixtures thereof, and the salts thereof.