Why does basil try to destroy he canvas?

Basil tries to destroy the canvas in a moment of desperation and conflict over his feelings for Dorian Gray and the moral implications of his artwork. He realizes that the portrait has captured Dorian's corrupting influence and reflects the darker aspects of his soul. Basil believes that by destroying the painting, he can also eliminate the negative impact it has had on Dorian’s life and perhaps redeem both himself and Dorian. Ultimately, this act symbolizes his internal struggle between artistic expression and moral responsibility.