Lithium hydroxide, monohydrate → 2-{[(1R,10R,11S,16S)-3-hydroxy-1,11,15,15-tetramethyl-8,8-dioxo-8lambda6-thiatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-trien-5-yl]formamido}acetic acid

Participants

Reaction Steps

A mixture of methyl 2-{[(1R,10R,11S,16S)-3-hydroxy-1,11,15,15-tetramethyl-8,8-dioxo-8λ6-thiatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-trien-5-yl]-formamido}acetate (92) (0.07 g, 0.2 mmol) and LiOH.H2O (0.07 g, 2 mmol) in MeOH (10 mL) and water (2.0 mL) was stirred at room temperature for 18 h. The reaction mixture was concentrated under reduced pressure, the aqueous residue was acidified with 1 M HCl and the resulting solid was collected by filtration to give 2-{[(1R,10R,11S,16S)-3-hydroxy-1,11,15,15-tetramethyl-8,8-dioxo-8λ6-thiatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-trien-5-yl]formamido}acetic acid (93) (0.057 g, 84%) as a pale brown solid. 1H NMR (CD3OD): δ 7.79 (d, 1H), 7.43 (d, 1H), 4.07 (s, 2H), 3.60 (d, 1H), 3.38 (m, 2H), 2.26 (d, 1H), 1.86-1.16 (m, 12H), 1.10-1.00 (m, 5H), 0.90 (s, 3H), 0.88 (s, 3H). MS m/z 462 (C24H33NO6S−H+).

Provenance & Evidence