Application of Chiral Transfer Reagents to Improve Stereoselectivity and Yields in the Synthesis of the Antituberculosis Drug Bedaquiline

Abstract

Bedaquiline (BDQ) is an important drug for treating multidrug-resistant tuberculosis (MDR-TB), a worldwide disease that causes more than 1.6 million deaths yearly. The current synthetic strategy adopted by the manufacturers to assemble this molecule relies on a nucleophilic addition reaction of a quinoline fragment to a ketone, but it suffers from low conversion and no stereoselectivity, which subsequently increases the cost of manufacturing BDQ. The Medicines for All Institute (M4ALL) has developed a new reaction methodology to this process that not only allows high conversion of starting materials but also results in good diastereo-and enantioselectivity toward the desired BDQ stereoisomer. A variety of chiral lithium amides derived from amino acids were studied, and it was found that lithium (R)-2-(methoxymethyl)pyrrolidide, obtained from D-proline, results in high assay yield of the desired syn-diastereomer pair (82%) and with considerable stereocontrol (d.r. = 13.6:1, e.r. = 3.6:1, 56% ee), providing BDQ in up to a 64% assay yield before purification steps toward the final API. This represents a considerable improvement in the BDQ yield compared to previously reported conditions and could be critical to further lowering the cost of this life-saving drug.

A Tandem Ring Closure and Nitrobenzene Reduction with Sulfide Provides an Improved Route to an Important Intermediate for the Anti-Tuberculosis Drug Candidate Sutezolid

“…As an additional complication, a lack of treatment options can give rise to multidrug-resistant TB strains (MDR-TB) . After a decades-long drought of new TB treatments, several new drugs have been developed in recent years, including bedaquiline, , linezolid, pretomanid, and delamanid, and combination regimens of these drugs such as BPaL. , However, ensuring low costs for these new treatment options remains a top priority for the global health community.…”