What are the Russian equivalents to these names?

David is David, right, second syllable stressed. the other three don't have ANY equivalents in russian. by that i mean there are russian-ized versions of these foreign names (either english or german), which doesn't make them russian. Names that do have some common equivalents include John (for either Ivan or Evgeni), Nicholas (for Nikolai), Dennis, Arthur... i can think of a few more but none of them are Jonathan or Grant :)