The present invention relates to a method of synthesizing a compound of formula (I) also referred to as 4-(((2S,4S)-(4-ethoxy-1-(((5-methoxy-7-methyl-1H-indol-4-yl)methyl)piperidin-2-yl))benzoic acid, or a pharmaceutically acceptable salt thereof, and/or intermediates thereof, their use as pharmaceuticals and pharmaceutical compositions and the use of intermediates for preparing a compound of formula (I), or a pharmaceutically acceptable salt thereof.