Abstract: The present invention relates to the metabolites of 2-{3-[4-(2-isopoxyphenyl) piperazin-1-yl]-propyl}-3a,4,7,7a-tetrahydro-1h-isoindole-1,3(2H)-dione of formula 1. The disclosed compounds can function as alpha1a-adrenoceptor antagonists and thus can be used for the treatment of benign prostatic hyperplasia (BPH) and related symptoms thereof. Processes for preparing the meatabolites, pharmaceutical composition containing these metabolites and the method of treating BPH and related symptoms thereof are also provided.