The present invention relates to a compound of formula (I), a pharmaceutically or cosmetically acceptable salt thereof, or any stereoisomer thereof, wherein R’ is selected from the group consisting of H, (C1-C6)-
alkyl, and (C3-C6)-cycloalkyl; R1, R2, R4, R5, R6, R7, R9, and R 10 are independently radicals selected from the group consisting of H, hydroxy, amino, (C1-C6)-
alkyl, (C1-C6)-alkoxy, (C1-C6)-alkylamino, and (C1-C6)-dialkylamino; R3 and R8 are independently selected from the group consisting of (C1-C6)-
alkyl, (C1-C6)-alkoxy, hydroxy, amino, (C1-C6)-alkylamino, and (C1-C6)-dialkylamino), and relates to a process for preparing the same, which process comprises a beta-
elimination reaction of the corresponding alkyl
halide precursor in the presence of DBU and a suitable
solvent. The present invention also relates to intermediates useful in such a preparation process. [Chemical 1] TIFF2025522152000022.tif95160