Trifluoroacetic acid → HCID 86757769, compound

Methyl N-(t-butoxycarbonyl)leucine-3-amino-5-hexenoate (10 g) was treated with 90% TFA in water(100 ml). The mixture was stirred for 30 min and the TFA and water were then removed by evaporation. The residue was purified by preparative HPLC on a C18 silica column eluting with acetonitrile/water/0.1% TFA to give a gummy solid on evaporation of appropriate fractions. This was dissolved in ethyl acetate (50 ml) and washed twice with saturated sodium bicarbonate solution(10 ml), once with saturated brine(10 ml), dried (MgSO4) and evaporated to give 1.6 g of a single diastereoisomer of methyl leucine-3-amino-5-hexenate as a pale blue oil. HPLC Dynamax 60A C18 column; acetonitrile/water/0.1%TFA 10-70% over 20 min Rt 10.7 min; 1H NMR (DMSO-d6, 300 MHz, ppm): 0.9(6H, m), 1.4-1.5 (2H, m), 1.5-1.7 (1H, m), 2.1-2.3(2H, m), 2.3-2.5(2H, m), 3.5 (3H, s), 3.6-3.7(1H, m), 4.1-4.2(1H, m), 4.4-4.6 (2H, b), 5.0-5.1 (2H, dd), 5.6-5.8 (1H, m), 8.4 (1H, d): m/Z 257 (M+H).

1. customthe TFA and water were then removed by evaporation
2. customThe residue was purified by preparative HPLC on a C18 silica column
3. washeluting with acetonitrile/water/0.1% TFA
4. customto give a gummy solid
5. customon evaporation of appropriate fractions
6. dissolutionThis was dissolved in ethyl acetate (50 ml)
7. washwashed twice with saturated sodium bicarbonate solution(10 ml), once with saturated brine(10 ml)
8. dry with materialdried (MgSO4)
9. customevaporated

ORD record

ord-ff676ab01d6144539c08fc9d2338e292

Source dataset

uspto-grants-2002_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06344570B1