Introduction of Abametapir

Abametapir(5,5′-Dimethyl-2,2′-dipyridyl) is a topical drug used for the treatment of head lice infestation. The compound inhibits metalloproteinase enzymes critical for the growth and development of lice eggs. In July 2020, the USFDA approved the drug for use on patients 6 months of age and older. Dr. Reddy's Laboratories obtained marketing rights for this drug, which is sold as a 0.74% weight by weight emulsion in an undisclosed ratio of water, benzyl alcohol, trolamine, polysorbate 20, and light mineral oil.

Synthesis of Abametapir

Abametapir(5,5′-Dimethyl-2,2′-dipyridyl) is prepared in two steps from 2-amino-5-methylpyridine. The specific synthesis steps are as follows:

A Sandmeyer reaction with bromine and sodium nitrite converted 2-amino-5-methylpyridine to 2-bromo-5-methylpyridine in 75% yield. Next, palladium-catalyzed homocoupling furnished abametapir in 79% yield. The final product was isolated by crystallization from a water/isopropanol mixture prior to its preparation as the topical therapeutic.