TK 781 then GQ 671 at Istanbul
Doha → Istanbul → Athens
Timetable, Istanbul time
06:35TK 781 from Doha at the gate
22:45GQ 671 to Athens leaves the gate
16 h 10 apart on the timetable
GQ 671 leaves 16 h 10 after TK 781 arrives on the timetable: more than half a day, so not a connection we count.