IB 5353 then QR 3545 at Barcelona
Milan → Barcelona → Santiago de Compostela
Timetable, Barcelona time
11:55IB 5353 from Milan at the gate
09:10QR 3545 to Santiago de Compostela leaves the gate
21 h 15 apart on the timetable, overnight
QR 3545 leaves 21 h 15 after IB 5353 arrives on the timetable: more than half a day, so not a connection we count.