2,3,4,6-Tetrachlorodibenzo[b,d]fur

2,3,4,7-四氯二苯并呋喃

2,3,4,8-四氯二苯并呋喃

1,3,4,6,7-五氯二苯并呋喃

1,2,6,8-四氯二苯并呋喃