N-[(4aR,6R,8aS)-8a-(2,4-difluorophenyl)-6-(hydroxymethyl)-4,4a,5,6,8,8a-hexahydropyrano[3,4-d][1,3]thiazin-2-yl]benzamide → N-[(4R,4aR,6R,8aS)-8a-(2,4-difluorophenyl)-6-(hydroxymethyl)-4-methyl-4,4a,5,6,8,8a-hexahydropyrano[3,4-d][1,3]thiazin-2-yl]benzamide

Participants

Reaction Steps

The product was prepared from N-[(4R,4aR,6R,8aS)-6-[(benzyloxy)methyl]-8a-(2,4-difluorophenyl)-4-methyl-4,4a,5,6,8,8a-hexahydropyrano[3,4-d][1,3]thiazin-2-yl]benzamide (C18) according to the general procedure for the synthesis of N-[(4aR,6R,8aS)-8a-(2,4-difluorophenyl)-6-(hydroxymethyl)-4,4a,5,6,8,8a-hexahydropyrano[3,4-d][1,3]thiazin-2-yl]benzamide (P1) in Preparation P1. In this case, the combined crude product from two similar reactions was triturated with dichloromethane rather than being purified by chromatography. The filtrate from the trituration was concentrated in vacuo, and a second crop of material was obtained via a second trituration with dichloromethane, affording the product in both cases as a white solid. Total yield: 23.12 g, 53.46 mmol, 79%. LCMS m/z 433.2 [M+H+]. 1H NMR (400 MHz, CD3OD) δ 8.12 (br d, J=7 Hz, 2H), 7.51-7.57 (m, 1H), 7.40-7.49 (m, 3H), 7.02-7.11 (m, 2H), 4.15 (br d, J=12 Hz, 1H), 3.91 (d, J=11.9 Hz, 1H), 3.71-3.78 (m, 1H), 3.60 (d, J=5.2 Hz, 2H), 3.19-3.28 (br m, 1H), 2.97-3.06 (br m, 1H), 1.74-1.82 (m, 1H), 1.49-1.62 (m, 1H), 1.26 (d, J=7.0 Hz, 3H).

Provenance & Evidence