Illustrated Glossary of Organic Chemistry

DNA alkylator: A molecule that alkylates DNA, usually at a guanine NH2 group. DNA alkylators can have mutagenic, pharmaceutical, or other effects.

Mechlorethamine (shown in blue) is an anticancer agent that works by DNA alkylation. DNA is shown in red. The DNA nucleophile is a guanine NH2 group. A pair of SN2 reactions with anichimeric assistance produces a bridge across the two strands of the DNA double helix. This bridge interferes with DNA function and replication.