<unk>  is a substance that is being studied in the treatment of cancer. It belongs to the family of drugs called alkylating agents. It has been used mainly as a substitute of busulfan in frail patients, as the side effects and toxicity are supposedly less severe.
Treosulfan
Mannosulfan
Carbosulfan
Isosulfan blue
Indigotindisulfonate
Imidazolidinyl urea
Isoprocarb
Bithionol