Yasmani Copello Escobar misses gold by fraction of a second in London
Escobar finished in a time of 48.49 seconds, behind Norway’s Karsten Warholm who took gold in 48.35 seconds.
America's Olympic champion Kerron Clement settled for bronze in the event.
Escobar, originally from Cuba, won the bronze at the Rio Olympics and gold at the European Championships.
Turkey sent a record 27 athletes to the 10-day competition that began Aug. 4.