Convert raw collection to DNG - Application idea


I have a large collection of photos/raw files, all ordered by year folders and event sub folders:

2001.02.24 - Event name
2001.03.15 - Another photo event
2002.01.22 - Photo event
2002.02.14 - The best event

And so on...

It's a rather large collection and I'd like to convert the raw files, not the jpegs, to DNG to optimize size and maintain edits inside one file instead of external xmp-files.

I'm looking for a software that can do that in a large batch kind of way. Let's say I have my collection in:
Mac drive: user/photocollection
I would like for the converted files to be placed under
Mac drive: user/converted
But still contain all the sub folder structures, and for the jpegs (and any other files) just to be copied into the converted folder.

All the software I can find only converts a single photo, or perhaps just one folder. And I can't be the only one that have this problem?