The present invention is relates to a compound of formula (I), wherein X1, X2 and X3 are, independently of each other, N or CH; with the proviso that at least two of X1, X2 and X3 are N; Y is N or CH; W is H or F; with the proviso that when W is F, then X1, X2 and X3 are N; R1 and R2 are independently of each other (i) a morpholinyl of formula (II) wherein the arrow denotes the bond in formula (I); and wherein R3 and R4 are independently of each other H, C1-C3alkyl optionally substituted with one or two OH, C1-C2fluoroalkyl, C1-C2alkoxy, C1-C2alkoxyC1-C3alkyl, CN, or C(O)O—C1-C2alkyl; or R3 and R4 form together a bivalent residue —R5R6— selected from C1-C3alkylene optionally substituted with 1 to 4 F, —CH2—O—CH2—, —CH2—NH—CH2—, or any of the structures wherein the arrows denote the bonds in formula (II); or (ii) a saturated 6-membered heterocyclic ring Z selected from thiomorpholinyl and piperazinyl, optionally substituted by 1 to 3 R7; wherein R7 is independently at each occurrence C1-C3alkyl optionally substituted with one or two OH, C1-C2fluoroalkyl, C1-C2alkoxyC1-C3alkyl, C3-C6cycloalkyl; or two R7 substituents form together a bivalent residue —R8R9— selected from C1-C3alkylene optionally substituted with 1 to 4 F, —CH2—O—CH2— or —O—CH2CH2—O—; with the proviso that at least one of R1 and R2 is a morpholinyl of formula II; and prodrugs, metabolites, tautomers, solvates and pharmaceutically acceptable salts thereof, for use in the prevention or treatment of a skin lesion in a subject.