Chemical structure of AT9283 and model of AT9283 bound with ABL. (A) Chemical structure of AT9283. (B) AT9283 does not make a hydrogen bond interaction with T315 in the same way other kinase inhibitors in the class do. The pocket behind the T315 gatekeeper is not occupied by AT9283. Its potency for ABL kinase is not abrogated by mutation of this residue to the bulkier isoleucine (T315I).