R¹ represents OH, SH, NH₂, NHCH₃, N(CH₃)₂, CH₃, CH₂Cl, CH₂F, CHF₂, CF₃, OCH₃, OCH₂Cl, OCH₂F, OCHF₂, OCF₃, C₂H₅, CHClCH₃, CH₂CH₂Cl, CHFCH₃, CH₂CH₂F, CH₂CHF₂, CH₂CF₃, OC₂H₅, COOH, CH₂OH, CHOHCH₃ or CH₂CH₂OH,

R² represents H or CH₃,

R³ represents H;

R⁴ represents H; or

an alkyl radical selected from the group consisting of methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, propyl, 2-methylpropyl, 1-methylpropyl, 1-ethylpropyl, butyl, i-butyl, n-butyl, tert-butyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylbutyl, pentyl, 2-methylpentyl, 3-methylpentyl, 1,1-dimethylethyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl and dodecyl; wherein said alkyl radical is unsubstituted or mono- or polysubstituted by a substituent selected from the group consisting of F, Cl, Br, I, NH₂, SH and OH; or

a cyclic radical selected from the group consisting of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cycloheptenyl and cyclooctenyl, wherein said cyclic radical is unsubstituted or mono- or polysubstituted by a substituent selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, CF₃, methoxy and ethoxy; or

a radical corresponding to formula II

 wherein n represents a number from 0 to 6,

m represents a number from 0 to 6,

1≤m+n ≤6

X represents O, S, SO, SO₂ or NR₇, and

each R independently represents H, F, Br, I, Cl, OH, SH, NH₂, NO₂, CH₃, C₂H₅, OCH₃, OC₂H₅, or OCF₃;

R⁵ represents H; an alkyl radical selected from the group consisting of methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, propyl, 2-methylpropyl, 1-methylpropyl, 1-ethylpropyl, butyl, i-butyl, n-butyl, tert-butyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylbutyl, pentyl, 2-methylpentyl, 3-methylpentyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl and hexyl, wherein said alkyl radical is unsubstituted or mono- or polysubstituted by a substituent selected from the group consisting of F, Cl, Br, I, NH₂, SH and OH; or a cyclic radical selected from the group consisting of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cycloheptenyl and cyclooctenyl, wherein said cyclic radical is unsubstituted or mono- or polysubstituted by a substituent selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, CF₃, methoxy and ethoxy;

R⁶ represents H; an alkyl radical selected from the group consisting of methyl, ethyl, 1-methylethyl, 1,1-dimethylethyl, propyl, 2-methylpropyl, 1-methylpropyl, 1-ethylpropyl, butyl, i-butyl, n-butyl, tert-butyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylbutyl, pentyl, 2-methylpentyl, 3-methylpentyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl and hexyl; wherein said alkyl radical is unsubstituted or mono- or polysubstituted by a substituent selected from the group consisting of F, Cl, Br, I, NH₂, SH and OH; or a cyclic radical selected from the group consisting of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cycloheptenyl and cyclooctenyl, wherein said cyclic radical is unsubstituted or mono- or polysubstituted by a substituent selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, CF₃, methoxy and ethoxy; or a radical corresponding to formula IIa

or the radicals R⁵ and R⁶ together form a ring and denote CH₂CH₂OCH₂CH₂, CH₂CH₂NR11CH₂CH₂ or (CH₂)_3-6,

R⁷ represents H; or an alkyl radical selected from the group consisting of methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl, 1,1-dimethylethyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl and hexyl; or a cyclic radical selected from the group consisting of cyclopropyl, 2-methylcyclopropyl, cyclopropylmethyl, cyclobutyl, 2-methylcyclobutyl, 3-methylcyclobutyl, cyclobutylmethyl, cyclopentyl, cyclohexyl, and cyclooctyl; or an acyl radical C(O)R8 or a sulfonyl radical S(O₂)R9,

R⁸ represents H; or an unsubstituted alkyl radical selected from the group consisting of methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl, 1,1-dimethylethyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, hexyl, and 1-methylpentyl; or an aryl radical selected from the group consisting of phenyl, 3-hydroxyphenyl, 3-methoxyphenyl, 2,3-dihydroxyphenyl, 2,3-dimethoxyphenyl and 1-naphthyl;

R⁹ represents H; or an unsubstituted alkyl radical selected from the group consisting of methyl, ethyl, propyl, methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl, 1,1-dimethylethyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, hexyl, and 1-methylpentyl; or an aryl radical selected from the group consisting of phenyl, 3-hydroxyphenyl, 3-methoxyphenyl, 2,3-dihydroxyphenyl, 2,3-dimethoxyphenyl and 1-naphthyl;

R¹¹represents H; or an unsubstituted alkyl radical selected from the group consisting of methyl, ethyl, propyl, I-methylethyl, butyl, I-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, hexyl, and 1-methylpentyl; or an unsubstituted cycloalkyl radical selected from the group consisting of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cycloheptenyl and cyclooctenyl; or an aryl radical selected from the group consisting of phenyl, 3-hydroxyphenyl, 3-methoxyphenyl, 2,3-dihydroxyphenyl, 2,3-dimethoxyphenyl and 1-naphthyl; or an unsubstituted heteroaryl radical selected from the group consisting of pyrrolyl, furyl, thienyl, pyrazolyl, imidazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyranyl, indolyl, indazolyl, purinyl, pyrimidinyl, indolizinyl, quinolinyl, isoquinolinyl, quinazolinyl, carbazolyl, phenazinyl and phenothiazinyl; or an aryl radical which is bonded via C_1-3-alkylene and is selected from the group consisting of phenyl, 3-hydroxyphenyl, 3-methoxyphenyl, 2,3-dihydroxyphenyl, 2,3-dimethoxyphenyl and 1-naphthyl; or an unsubstituted heteroaryl radical which is bonded via C_1,3-alkylene and is selected from the group consisting of pyrrolyl, furyl, thienyl, pyrazolyl, imidazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyranyl, indolyl, indazolyl, purinyl, pyrimidinyl, indolizinyl, quinolinyl, isoquinolinyl, quinazolinyl, carbazolyl, phenazinyl and phenothiazinyl; or an acyl radical C(O)R¹²; or a sulfonyl radical S(O₂)R¹³;

R¹² represents H; or an unsubstituted alkyl radical selected from the group consisting of methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, hexyl, and 1-methylpentyl; or an aryl radical selected from the group consisting of phenyl, 3-hydroxyphenyl, 3-methoxyphenyl, 2,3-dihydroxyphenyl, 2,3-dimethoxyphenyl and 1-naphthyl;

R¹³ represents H; an unsubstituted alkyl radical selected from the group consisting of methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, hexyl, and 1-methylpentyl; or an aryl radical selected from the group consisting of phenyl, 3-hydroxyphenyl, 3-methoxyphenyl, 2,3-dihydroxyphenyl, 2,3-dimethoxyphenyl and 1-naphthyl; and

R¹⁴ represents H, F, Br, I, Cl, OH, SH, NH₂, NO₂, CH₃, C₂H₅, OCH₃, OC₂H₅, or OCF₃;

or a pharmaceutically acceptable salt thereof,

with the proviso that the following compounds: