Trifluoroacetic acid → N-[(4aR,11bR)-2-amino-3,3,11b-trimethyl-4,4-dioxo-5,6-dihydro-4aH-[1]benzoxepino[4,5-b][1,4]thiazin-10-yl]-5-chloro-3-methylpyridine-2-carboxamide

Participants

Reaction Steps

A solution of trans-isomer tert-butyl ((4aR,11bR)-10-(5-chloro-3-methylpicolinamido)-3,3,11b-trimethyl-4,4-dioxido-4a,5,6,11b-tetrahydro-3H-benzo[6,7]oxepino[4,5-b][1,4]thiazin-2-yl)carbamate (110 mg, 0.191 mmol) in DCM (2 ml) was treated with TFA (0.7 ml, 9.53 mmol) for 10 min at RT. The mixture was concentrated to dryness, redissolved in 0.5 ml of MeOH and neutralized with saturated solution NaHCO3. The precipitated material was extracted with ethyl acetate, organic extract was washed with water, brine, filtered through pad of celite and concentrated to afford N-((4aR,11bR)-2-amino-3,3,11b-trimethyl-4,4-dioxido-4a,5,6,11b-tetrahydro-3H-benzo[6,7]oxepino[4,5-b][1,4]thiazin-10-yl)-5-chloro-3-methylpicolinamide (Example 6a) (89 mg, 0.187 mmol, 98% yield).

Provenance & Evidence