Types thumb|left| Two DNA bases that are cross-linked by a nitrogen mustard. Different nitrogen mustards will have different chemical groups (R). The nitrogen mustards most commonly alkylate the N7 nitrogen of guanine (as shown here) but other atoms can be alkylated.
tYpEs tHuMb|lEft| ,two dNA baseS that are cRoSs-LinKED bY a nItRoGEn mUStarD. dIffeReNT ?NITrOGEN musTardS will have DIFfEreNt chemIcaL grOuPs (r). the niTRogen mustARds mOst CommOnLy ALKYlate THe n7 NItroGen oF guanInE (as SHowN Here) but otheR atoMs can be alkYLated.