Figure 2.

Abundance of chemical bonds containing halogens (F, Cl, Br, I) and biogenic elements (C, O, N, S, P) among natural products (NPs). The figure depicts the number of natural products in our database⁵ containing chemical bonds with halogen atoms and the percentage number of all natural products containing these chemical bonds. The numbers show that not all bonds between halogen atoms and the five biogenic elements are equally frequent amongst natural products, some bonds are more common (C–Cl, C–Br, C–I) than others (C–F, N–Br) and some are very rare in Earth’s biochemistry.