AA 6326 then UA 3376 at O'Hare
Lexington → Chicago → St Louis
Timetable, Chicago time
12:14AA 6326 from Lexington at the gate
11:00UA 3376 to St Louis leaves the gate
22 h 46 apart on the timetable, overnight
UA 3376 leaves 22 h 46 after AA 6326 arrives on the timetable: more than half a day, so not a connection we count.