Novel dicarboxylic acid derivatives as s1p1 receptor agonists

A compound of formula (I):

• wherein
• represents a 1,2,4-oxadiazole group;
• X1 is a mono-, bi- or tricyclic ring structure selected from aryl, heteroaryl, heterocyclic group or cycloalkyl group optionally comprising one or more unsaturations;
• R1 is selected from the group consisting of hydrogen, halo, perhaloalkyl, perhaloalkoxy, aryl, arylalkyl, alkylaryl, alkyl, alkenyl, alkynyl, —N(R2)2 and cycloalkyl optionally comprising one or more unsaturations;
• wherein the aryl group may be fused with a ring comprising 2 to 5 atoms selected from carbon or heteroatom;
• further wherein each R1 is optionally substituted from one up to the maximum number of substitutable positions with a substituent independently selected from a group consisting of halo, -alkyl, —O-alkyl, cycloalkyl, aryl, arylalkyl, alkylaryl and perhaloalkyl;
• and
• each R2 is independently selected from, hydrogen, -alkyl, -cycloalkyl, —CO—(O)r -alkyl, —CO—(O)r-cycloalkyl, —O—CO-alkyl, —O—CO-cycloalkyl, wherein r is 0 or 1;
• Y1 represents a bond or Y1 is selected from a group consisting of —O—;
• —S(O)q—, wherein q is 0, 1 or 2;
• and —C=Q-, wherein Q is O, S, N—R′ or N—OR′, wherein R′ is selected from hydrogen, -alkyl, -alkenyl, -alkynyl, -alkoxy, -cycloalkyl or -perhaloalkyl;
• each moiety R1-Y1, identical or different, represents a group that is attached to the cyclic ring structure X1 and m is an integer selected from 1 to 9, wherein m represents the number of positions on X1 substituted with a R1-Y1 moiety.
• Y2 represents a bond or Y2 is selected from a group consisting of —O—;
• —CH2—;
• —C(O)O—;
• —C(O)NH—;
• —S(O)q—, wherein q is 0, 1 or 2;
• and —C=Q-, wherein Q is O, S, N—(R′)2 or N—OR′, wherein each R′ is independently selected from hydrogen, -alkyl, -alkenyl, -alkynyl, -alkoxy, -cycloalkyl or -perhaloalkyl;
• R3 is selected from the group consisting of hydrogen, halo, -alkyl, —O-alkyl, perhaloalkyl and —N(R2)2 wherein R2 is as defined above;
• and p is an integer selected from 1 to 4;
• R4 and R5 are independently selected from the group consisting of hydrogen, methyl and -cycloalkyl or R4 and R5 together with the C atom to which they are attached form a -cycloalkyl group;
• R6 is selected from the group consisting of hydrogen, -alkyl, -alkenyl, -alkynyl and -cycloalkyl;
• Z represents a -cycloalkyl group, or R6 and Z form together with the N atom to which they are attached a 5 to 8 membered heterocyclic ring;
• the —CO2R7 and —COR8 groups are attached to the same atom, wherein the —CO2R7 group represents a —CO2H group or an ester derivative thereof and the —COR8 group represents a —CO2H group or an ester or an amide derivative thereof,
• as well as their enantiomers, diastereomers, mixtures thereof and pharmaceutically acceptable salts, hydrates and solvates.