Dan is already an English name - it's a nickname for Daniel (DAN-yel). Your boyfriend can just go by Dan and no-one will think it strange.
I gave you some suggestions for Ting - Tina (TEE-na) and Tiane (tee-AHN). You could also use Tiana (tee-AH-na) or Tianna (tee-AN-a)
♦ Chrisell ♦
All we have to decide is what to do with the time that is given us. - J.R.R. Tolkien.