Complex sentence: On learning of the commission, William Burn sought an interview with the prince, apparently to complain that Smith previously had plagiarised his work, however, Burn was unsuccessful in depriving Smith of the appointment.
Split into simpler sentences: On learning of the commission, William Burn sought an interview with the Prince, apparently to complain that Smith had plagiarised his work in the past. However, Burn was unsuccessful in depriving Smith of the appointment.