<unk>  is an alkylsulfonate. It is an alkylating agent that forms DNA-DNA interstrand crosslinks between the DNA bases guanine and adenine and between guanine and guanine. This occurs through an SN2 reaction in which the relatively nucleophilic guanine N7 attacks the carbon adjacent to the mesylate leaving group. DNA crosslinking prevents DNA replication. Because the intrastrand DNA crosslinks cannot be repaired by cellular machinery, the cell undergoes apoptosis.
Busulfan
Ifosfamide
Vincristine
Carmustine
Lomustine
Cladribine
Melphalan
Ixazomib