Split large file in classes

I was wondering if it is possible to split a large (autogenerated) file in multiple files using Resharper. It should split the file in fiels each containing one class from the original file.

I thought it might be a feature suited for Resharper, but I can't find the functionality. And I cannot find another tool which is able to do the job.

My problem arise because:
I have some service contracts from wsdl files which I autogenerate classes for. The tool that autogenerate these classes puts all files in the same file, so the file becomes rather huge (~2.5 mb and ~65k lines). All these classes are partial and when I extend one class in another file, it takes ages for Resharper to analyse the class for syntactic/semantic errors. I guess it is because it has to analyse the huge file to get a result.