L-Cysteine, methyl ester → Methyl 2-amino-3-(3,7,11-trimethyldodeca-2,6,10-trienylsulfanyl)propanoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Into a 100 mL round bottomed flask at 0° C. is added L-Cysteine methyl ester (1.38 g, 10.2 mmols) in 60 mL of 7M NH3/MeOH. Neat farnesyl bromide (1b) (1.00 g 3.52 mmols) is then added and the solution is stirred at 0° C. for four hours. The reaction mixture is partitioned between ether and water and extracted 3× with ether, extracts are combined, dried over MgSO4 filtered and evaporated. Purification by flash chromatography (1% MeOH:CHCl3) yields 881 mg (74%) of a clear oil. Rf=0.22 in 5% MeOH in CHCl3. 1H NMR (CDCl3, 400 MHz): 5.24 (t, 1H, J=8 Hz), 5.10 (m, 2H), 3.75 (s, 3H), 3.64 (q, 1H), 3.10-3.25 (m, 2H), 2.86-2.91 (2d, 1H), 2.65-2.71 (2d, 1H), 2.04-2.10 (m, 6H), 2.04(m, 6H) 2.0 (t, 2H), 1.69 (s, 3H), 1.68 (s. 3H), 1.60 (s, 6H); 13C NMR (CDCl3, 50 MHz) 174.93, 139.91, 135.71, 131.62, 124.69, 124.11, 120.35, 54.64, 52.35, 39.93, 36.77, 30.15, 26.98, 26.67, 25.86, 17.86, 16.33, 16.21 MS: (ESI, +) (M−H+) 340

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