Tottenham announced the moves Monday, with European clubs still able to sell players to Turkish teams even though the European transfer window shut on Friday.
Sanchez hasn't started any of Tottenham's opening four Premier League games under new manager Ange Postecoglou, who had said he wanted to trim a bloated squad.
Tottenham did not disclose the transfer fee for Sanchez, a Colombian center back who had been with the London club for six years and made made 207 appearances after joining from Ajax.
Ndombele joins Galatasaray on loan for the remainder of the season, with the option to make the move permanent.
It is Ndombele's third consecutive loan spell away from Spurs since he joined in 2019.
AP soccer: https://apnews.com/hub/soccer
The Associated Press