Gianluca di Marzio writes on his blog that Borussia Dortmund could be interested in Ranocchia:

“Andrea Ranocchia is appreciated in Germany. The interest comes from Borussia Dortmund who are following the situation of the player at Inter. The Germans want a player who could represent them in the Champions League straight away, because of their injury problems in defense. Inter hasn’t got any fax or a phone call, but they will probably receive it in the coming days. Dortmund are following Ranocchia but his name isn’t the only on the list.”
Source: Gianlucadimarzio.com