UA 3851 then TK 34 at Houston
Mexico City → Houston → Istanbul
Timetable, Houston time
08:23UA 3851 from Mexico City at the gate
21:00TK 34 to Istanbul leaves the gate
12 h 37 apart on the timetable
TK 34 leaves 12 h 37 after UA 3851 arrives on the timetable: more than half a day, so not a connection we count.