MK-0822

MK-0822 is a newly developed bone-targeting dual action pro-drug for osteoporosis and bone metastasis. It is also an inhibitor of cathepsin K, an enzyme involved in bone resorption.

This investigational osteoporosis/bone-metastasis drug (FW = 525.56 g/mol; CAS 603139-19-1), also known by the code name MK-0822 and its systematic name N-(1-cyanocyclopropyl)-4-fluoro-N2-{(1S)-2,2,2-trifluoro- 1-[4'-(methylsulfonyl)biphenyl-4-yl]ethyl}-L-leucinamide, targets the cathepsin K, a unique collagenolytic lysosomal cysteine protease that is secreted, thereby facilitating bone resorption by cleaving type-1 collagen under acidic pH. Cathepsin K exhibits a unique cleavage pattern of type I collagen molecules that is fundamentally different from that of other endogenous collagenases. Women receiving ODN (10-50 mg) for 5 years had gains in spine and hip bone mineral density (BMD), showing larger reductions in bone resorption than bone formation markers. Significantly, discontinuation of ODN resulted in reversal of treatment effects. An odanacatib synthesis, which describes a novel stereospecific SN2 triflate displacement of a chiral a-trifluoromethylbenzyl triflate with (S)-g-fluoroleucine ethyl ester, achieves a 61% overall yield in 6 steps.