Tetrahydro-β-carbolin-sulfonamide derivatives as 5-Ht6 ligands

A tetrahydro-β-carbolin-sulfonamide derivative of general formula (I):

• wherein
• R1 and R2 represent hydrogen
• R3 represents C1-C6 alkyl, optionally substituted with one or more substituents independently selected from —NO2;
• —NH2;
• —SH;
• —OH;
• —CN;
• —C(═O)—OH;
• —S(═O)2-OH;
• —C(═O)—NH2;
• —S(═O)2-NH2;
• —S(═O)2—Rf;
• —ORf;
• —SRf;
• —C(═O)—ORf;
• —N(Rf)—S(═O)2—Rg;
• —NH—Rf;
• —NRfRg;
• —C(═O)—NHRf, —C(═O)—NRfRg;
• —S(═O)2-NHRf, —S(═O)2-NRfRg;
• —O—C(═O)—Rf;
• —NH—C(═O)—Rf;
• —NRf—C(═O)—Rg;
• —NH—C(═O)—O—Rf;
• —NRf—C(═O)—O—Rg;
• —S(═O)2—O—Rf;
• an halogen atom;
• a linear or branched, saturated or unsaturated, optionally at least mono-substituted aliphatic radical;
• a saturated or unsaturated, optionally at least mono-substituted, optionally at least one heteroatom as a ring member containing cycloaliphatic radical, which may be bonded via a linear or branched alkylene group;
• or an optionally at least mono-substituted aryl or heteroaryl radical, which may be bonded via a linear or branched alkylene group;
• wherein Rf and Rg are independent from one another and each represent a linear or branched, saturated or unsaturated, optionally at least mono-substituted aliphatic radical;
• a saturated or unsaturated, optionally at least mono-substituted, optionally at least one heteroatom as a ring member containing cycloaliphatic radical, which may be bonded via a linear or branched alkylene group;
• or an optionally at least mono-substituted aryl or heteroaryl radical, which may be bonded via a linear or branched alkylene, alkenylene or alkinylene group;
• R4 represents hydrogen;
• R5 represents NRcSO2Rd, wherein
• Rc represents hydrogen or C1-4 alkyl optionally substituted with one or more substituents independently selected from C1-C6 alkyl, aryl, cyano, C1-C6 alkoxy and trifluoromethyl;
• Rd represents aryl or heteroaryl optionally substituted with one or more substituents independently selected from —NO2;
• —NH2;
• —SH;
• —OH;
• —CN;
• —C(═O)—OH;
• —S(═O)2-OH;
• —C(═O)—NH2;
• —S(═O)2-NH2;
• —S(═O)2—Rf;
• —ORf;
• —SRf;
• —C(═O)—ORf;
• —N(Rf)—S(═O)2-Rg;
• —NH—Rf;
• —NRfRg;
• —C(═O)—NHRf, —C(═O)—NRfRg;
• —S(═O)2—NHRf, —S(═O)2—NRfRg;
• —O—C(═O)—Rf;
• —NH—C(═O)—Rf;
• —NRf—C(═O)—Rg;
• —NH—C(═O)—O—Rf;
• —NRf—C(═O)—O—Rg;
• —S(═O)2—O—Rf;
• an halogen atom;
• a linear or branched, saturated or unsaturated, optionally at least mono-substituted aliphatic radical;
• a saturated or unsaturated, optionally at least mono-substituted, optionally at least one heteroatom as a ring member containing cycloaliphatic radical, which may be bonded via a linear or branched alkylene group;
• or an optionally at least mono-substituted aryl or heteroaryl radical, which may be bonded via a linear or branched alkylene group;
• wherein Rf and Rg, have the meaning defined above
• R6 represents hydrogen
• with the proviso that when Rc is hydrogen, Rd is other than phenyl substituted with isopropyl, phenyl substituted with mono- or di-fluoro-methoxy, phenyl substituted with di-fluoro-methyl, phenyl substituted with mono-, di- or tri-fluoro-methyl-ethyl, phenyl substituted with mono, di- or tri-fluoro-ethyl, phenyl substituted with difluoro-cyclopropyl, phenyl substituted with mono- or di-fluoro-methyl-di-fluoro-ethyl, pyrimidinyl substituted with propyl, or thiophenyl substituted with propyl;
• optionally in form of one of its stereoisomers, preferably enantiomers or diasteromers, a racemate or in form of a mixture of at least two of its stereoisomers, preferably enantiomers and/or diastereomers, in any mixing ratio, or a physiologically acceptable salt thereof.