Tetrahydrocarbazol derivatives as ligands for G-protein-coupled receptors (GPCR)

Compound of general formula (I)

• 6
• in which
• radical R1 is a hydrogen atom, a C2-C6 alkenyl radical or a C1-C6 alkyl radical, and can optionally be substituted with an aryl radical, hetaryl radical or the group —COOR1, whereby the aryl or hetaryl radical can be substituted with up to three substituents, which are selected independently of one another from the group that consists of —NO2, —CH3, —CF3, —OCH3, —OCF3 and halogen atoms, and
• radical R11 is a hydrogen atom, a C1-C12 alkyl radical, a C1-C12 aralkyl radical, an aryl radical, a hetaryl radical or the group —COCH3, and optionally can be substituted with a substituent that is selected from the group that consists of —CONH2, —COCH3, —COOCH3, —SO2CH3 and aryl radicals;
• radicals R2, R3, R4 and R5, independently of one another, in each case are a hydrogen atom, a halogen atom, the group —COOH, —CONH2, —CF3, —OCF3, —NO2, —CN, a C1-C6 alkyl radical, a C1-C6 alkenyl radical, a C1-C6 alkoxy radical, a C1-C12 aralkyl radical, an aryl or hetaryl radical;
• radical R6 is the group —CONR8R9, —COOR8, —CH2NR8R9, —CH2R8, —CH2OR8 or a C1-C12 alkenyl radical, which optionally is substituted with radicals R8 and R9,
• whereby radicals R8 and R9, independently of one another, in each case are a hydrogen atom, a C1-C12 alkyl radical, a C1-C12 aralkyl radical, a C1-C12 hetaralkyl radical, an aryl radical or hetaryl radical, which can be substituted with one or more substituents, which are selected from the group that consists of —OH, —NH2, —CONHR10, —COOR10, —NH—C(═NH)—NH2 and halogen atoms,
• whereby radical R10 is a hydrogen atom, a C1-C12 alkyl radical, a C1-C12 aralkyl radical, an aryl radical or hetaryl radical, and optionally is substituted with the group —CON(R11)2,
• or whereby radicals R8 and R9 together can form a ring structure that either consists exclusively of carbon atoms or, in mixed form, consists of carbon atoms and heteroatoms;
• radical R7 is a hydrogen atom, a C1-C12 alkyl radical, a C1-C12 alkenyl radical, a C1-C12 aralkyl radical, an aryl radical or a hetaryl radical, the group —NR12R13, —NHCOR14, —NHCONHR14, —NHCOOR14 or —NHSO2R14, and optionally can be substituted with one or more substituents, which are selected from the group that consists of —OH, —NH2, —CONH2, —COOH and halogen atoms,
• radicals R12 and R13, independently of one another, in each case are a hydrogen atom, a C2-C6 alkenyl radical or a C1-C12 alkyl radical and optionally can be substituted with one or more aryl or hetaryl radicals, which in turn can be substituted with up to three substituents, which independently of one another are selected from the group that consists of —NO2, —CH3, —CF3, —OCH3, —OCF3 and halogen atoms,
• and radical R14 is a hydrogen atom, a C1-C12 alkyl radical, a C1-C12 alkenyl radical, a C1-C12 aralkyl radical, an aryl radical or a hetaryl radical, which optionally can be substituted with one or more substituents, which are selected from the group that consists of —NO2, —CH3, —OR11, —CF3, —OCF3, —OH, —N(R11)2, —OCOR11, —COOH, —CONH2, —NHCONHR11, —NHCOOR11 and halogen atoms;
• and radicals Ra, Rb, Rc, Rd, Re and Rf, independently of one another, in each case are a hydrogen atom, a halogen atom, the group —COOH, —CONH2, —CF3, —OCF3, —NO2, —CN, a C1-C6 alkyl radical, a C1-C6 alkoxy radical, an aryl radical or a hetaryl radical;
• provided that the compound of general formula (I) is not selected from the group that consists of 3-amino-1,2,3,4-tetrahydrocarbazole-3-carboxylic acid, 3-amino-6-methoxy-1,2,3,4-tetrahydrocarbazole-3-carboxylic acid, 3-amino-6-benzyloxy-1,2,3,4-tetrahydrocarbazole-3-carboxylic acid, 3-acetamido-1,2,3,4-tetrahydrocarbazole-3-carboxylic acid, methyl-3-acetamido-1,2,3,4-tetrahydrocarbazole-3-carboxylate, (−)-menthyl-3-acetamido-1,2,3,4-tetrahydrocarbazole-3-carboxylate or 3-tert-butoxycarbonyl-amino-1,2,3,4-tetrahydrocarbazole-3-carboxylic acid.