Substituted thiazole or oxazole p2x7 receptor antagonists

A process for preparing a compound of the following formula (I) or a pharmaceutically acceptable salt thereof:

• including any stereochemically isomeric form thereof, wherein
• n is 1 or 2;
• Y represents oxygen or sulfur;
• each of R1 and R2 is independently selected from the group consisting of hydrogen, deuterium, halogen, C1-C4 alkyl, optionally substituted with hydroxy or halogen, such as hydroxymethyl, fluoromethyl, difluoromethyl, trifluoromethyl, C3-C6 cycloalkyl, optionally substituted with hydroxy or halogen, or C1-C4 alkyloxy;
• each of R3 and R4 is independently selected from the group consisting of hydrogen, halogen, C1-C4 alkyl, difluoromethyl, trifluoromethyl, C1-C4 alkyloxy, NR9R10, wherein R9 and R10 independently are hydrogen or C1-C4 alkyl, or 2-thiazolidin-1,1-dione;
• or the two R3 groups or the R3 and R4 groups taken together form a six membered heterocyclic ring containing a nitrogen atom;
• R5 is selected from hydrogen, halogen, or is an heterocyclic ring selected from pyrimidin-2-yl, pyridin-2-yl or pyrazin-2-yl, optionally substituted with halogen, C1-C4 alkyl, fluoromethyl, difluoromethyl, trifluoromethyl or C1-C4 alkyloxy;
• R7 is hydrogen or C1-C4 alkyl;
• the radical
• represents an optionally substituted azetidine, pyrrolidine, piperidine, morpholine, oxazepane or 1,2,3,4-tetrahydroisoquinoline ring, wherein each of R6 is independently selected from the group consisting of hydrogen, halogen, C1-C4 alkyl, C3-C6 cycloalkyl, C3-C6 spirocycloalkyl difluoromethyl, trifluoromethyl, C1-C4 alkyloxy, aryl, heteroaryl, C1-C4 aryloxy or C1-C4 arylalkoxy wherein the aryl group or heteroaryl group is optionally substituted with halogen C1-C4 alkyl, fluoromethyl, difluoromethyl, trifluoromethyl or C1-C4 alkyloxy,
• said process comprising the step of reacting a compound of formula (II):
• wherein the meanings of n, Y, A and R1, R2 and R6 are as defined above, with a compound of formula (III)
• wherein the meanings of R3, R4 and R5 are as defined above;
• or with a compound of Formula (IIIa):
• wherein the meanings of R3, R4 and R5 are as defined above, and W is a suitable leaving group and optionally converting the obtained compound of formula (I) into an addition salt thereof, and/or preparing stereochemically isomeric forms thereof.