The Toffees boss made Sevilla frontman Negredo his top deadline day transfer target but the two clubs could not agree a fee with Everton unable to go above the £8.6million they had earlier earmarked for the purchase of Leroy Fer.
The deal for the Dutch midfielder broke down when Everton tried to reschedule the payments to FC Twente when doubts emerged during the player's medical.
But Moyes was able to bring in promising full-back John Stones from Barnsley and the Toffees boss believes he has plenty of quality to work with heading forward.
He said: "We would obviously like more, but what the players have done up to now has meant that we are more than confident going into the rest of the season with what we have got.
"Yes, we would have liked to add to it, but it wasn't to be the case.
"We wanted to add players if we could who could go into the team and we tried to do that right up to the end, but for reasons out of our control it didn't happen. It wasn't for the want of trying, that is for sure.
"There were a couple of young players we were interested in and we took one of them in John Stones in the end.
"But a couple of targets we had in mind possibly for helping the first team right now, they were gone, probably a few days before (deadline day).
"We tried (for Negredo), but it didn't work. They wanted a lot more money than we offered."