Synthesis of deuterium-labelled analogues of NLRP3 inflammasome inhibitor MCC950

This study describes the syntheses of di, tetra and hexa deuterated analogues of the NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome inhibitor MCC950. In di and tetra deuterated analogues, deuteriums were incorporated into the 1,2,3,5,6,7-hexahydro-s-indacene moiety, whereas in the hexa deuterated MCC950 deuteriums were incorporated into the 2-(furan-3-yl)propan-2-ol moiety. The di deuterated MCC950 analogue was synthesised from 4-amino-3,5,6,7-tetrahydro-s-indacen-1(2H)-one 5. Tetra deuterated analogues were synthesised in 10 chemical steps starting with 5-bromo-2,3-dihydro-1H-inden-1-one 9, whereas the hexa deuterated analogue was synthesised in four chemical steps starting with ethyl-3-furoate 24. All of the compounds exhibited similar activity to MCC950 (IC₅₀?=?8?nM). These deuterated analogues are useful as internal standards in LC-MS analyses of biological samples from in vivo studies.