AA 1047 then UA 3376 at O'Hare
Philadelphia → Chicago → St Louis
Timetable, Chicago time
11:05AA 1047 from Philadelphia at the gate
11:00UA 3376 to St Louis leaves the gate
23 h 55 apart on the timetable, overnight
UA 3376 leaves 23 h 55 after AA 1047 arrives on the timetable: more than half a day, so not a connection we count.