Discovery of 1,2,3,4-Tetrahydrochromeno[3,4‑c]pyridin-5-one Derivatives as Novel MTHFD Inhibitors for the Treatment of Acute Myeloid Leukemia

One-carbon metabolism is essential for nucleotide biosynthesis
and redox homeostasis, and its key enzymes, MTHFD2 and MTHFD1, are
aberrantly activated in diverse cancers, particularly acute myeloid
leukemia (AML). Herein, we solved the X-ray crystallography of the
reported MTHFD inhibitor DS18561882 bound to MTHFD2 and performed
systematic structure–activity optimization, leading to the
identification of a highly selective MTHFD2 inhibitor (compound 31) and a dual MTHFD1/2 inhibitor (compound 34). Cocrystal structural analysis revealed that subtle modifications
of the aminosulfonamide motif dictate isoform selectivity by reshaping
hydrogen bond and hydrophobic networks within the MTHFDs active site.
Notably, the dual inhibitor 34 exhibited superior antiproliferative
activities across AML cell lines and induced marked tumor regression
in MOLM-13 xenograft models with minimal toxicity, outperforming the
reference compound DS18561882. Our findings establish rational design
principles for isoform-selective and dual MTHFD1/2 inhibitors and
highlight a combined MTHFD1/2 blockade as a promising therapeutic
strategy for AML.