The present invention relates to novel 5-(Heterocyclyl)alkyl-N- (arylsulfonyl)indole compounds of the formula (I), their derivatives, their stereoisomers, their pharmaceutically acceptable salts and pharmaceutically acceptable compositions containing them. The present invention also relates to a process for the preparation of above said novel compounds, their derivatives, their stereoisomers, their pharmaceutically acceptable salts and pharmaceutically acceptable compositions containing them. These compounds are useful in the treatment of various disorders that are related to 5-HT6 receptor functions. Specifically, the compounds of this invention are also useful in the treatment of various CNS disorders, hematological disorders, eating disorders, diseases associated with pain, respiratory diseases, genito-urological disorders, cardiovascular diseases and cancer.
