Looking at FamilySearch, the name seems to be written mostly Leuffgens in Düren during that time.
FamilySearch gives these children of the couple Augustin Leueffgens and Anna Barbara Suderlants:
- Johannes, baptized 23 Jun 1779 in Düren
- Bartholomäus, baptized 2 Oct 1792 in Düren and
- Wilhelm Heinrich, baptized 21 Sep 1788 in Düren (the mother is written Anna Barbara Sonderhends)
This is only that what is about Leufgens/Suderlants. There are a few of other records you should have a look at. I don't find Thomas in them, but maybe these ones are also helpful