What are the replacement patterns or tokens for Profile2 URL of a particular user?
Try like this 


First Install Pathauto Module.
Login in drupal as administrator, and goto Configuration. Under 'SEARCH AND METADATA' select 'URL aliases'.
Select 'Pattern' tab and goto 'USER PATHS' and click on 'REPLACEMENT PATTERNS' a list will appear.
Select 'Users' and again some more option will be displayed, select 'name' and the 'pattern for user account page paths should be displayed as '[user:name]' and save it.
In the same window 'Bulk update' tab and check mark the User Paths and click Update.


The following output will be http://example.com/username.