Are we capable of deliberatly creating DNA from inorganic compounds?
Yes we could.
It wouldn't be worth the effort since all the building blocks are available from biological sources, but if you really wanted to you could have a chemist prepare nucleotides from inorganic substances.
Commercial labs routinely build long strands of DNA from individual nucleotides. You can tell them what sequence you need and they will make it for you. There's a Wikipedia article on how it works.