data sources can not be renamed directly, but there is a workaround for this.
You can copy the data source and paste it, then you will be asked for a new name.
Afterwards you should create a new base view from that copied data source and overwrite the old base view with the new base view (give it the same name). You don't need to modify any dervied view.
Please also have a look at the article [How to replace a data source without modifying the derived views](https://community.denodo.com/kb/view/document/How%20to%20replace%20a%20data%20source%20without%20modifying%20the%20derived%20views?category=Data+Sources), which describes in further details, how to do it and what to consider.
Hope this helps!