7996 J. Am. Chem. Soc., Vol. 121, No. 35, 1999
Reichel et al.
pyl]-(R)-cysteine tert-Butyl Ester (6R). The title compound was
prepared according to the same procedure as described for compound
6R/S starting from 5R (1 g, 2.11 mmol). Compound 6R (1.99 g, 99%)
was obtained as a white powder: mp 45 °C.
29.5, 29.4, 29.2 (Cys-CH2, S-glyceryl-CH2, Pal-CH2), 28.0 (tBu-CH3),
25.6, 24.9, 22.7 (Pal-CH2), 14.1 (Pal-CH3). LSIMS: m/z ) 989 (100%,
[M + Na]+).
S-[2,3-Bis(palmitoyloxy)-(2S)-propyl]-N-palmitoyl-(R)-cysteine tert-
Butyl Ester (7S). The title compound was synthesized following the
procedure described for compound 7R. Compound 6S (530 mg, 0.56
mmol) was used as a starting material. Compound 7S (480 mg, 89%)
was obtained as a white solid: mp ) 62 °C.
1H NMR (CDCl3, 300 MHz): δ 7.76 (d, 2H, Fmoc-Ar., JCH,CH
)
7.7 Hz), 7.70 (d, 2H, Fmoc-Ar., JCH,CH ) 7.0 Hz), 7.39 (t, 2H, Fmoc-
Ar.), 7.31 (t, 2H, Fmoc-Ar.), 5.70 (d, 1H, NH, JCH,NH ) 5.0 Hz), 5.21-
5.09 (m, 1H, S-glyceryl-CH), 4.56-4.45 (m, 1H, Cys-CHR), 4.41-
1H NMR (CDCl3, 300MHZ) δ 6.28 (d, 1 H, NH, JNH,2 ) 7.4 Hz),
5.18-5.07 (m, 1H, S-glyceryl-CH), 4.70 (m, 1H, Cys-CHR), 4.31 (dd,
1H, S-Glyceryl-OCH2a, JHa,Hb ) 12.0 Hz, JHa,CH ) 3.5 Hz), 4.12 (dd,
1H, S-Glyceryl-OCH2b, JHb,CH ) 6.1 Hz), 3.02 (d, 2H, Cys-CH2), 2.72
(m, 2H, H-S-glyceryl-CH2), 2.35-2.26 (m, 4H, 2 Pal-C(O)CH2), 2.23
(t, 2H, Pal-C(O)CH2, J ) 7.7 Hz), 1.68-1.53 (m, 6H, 3x Pal-CH2),
4.33 (m, 1H, S-glyceryl-OCH2a), 4.31 (d, 2H, Fmoc-CH2, JCH,CH2
)
3.7 Hz), 4.23 (t, 1H, Fmoc-CH), 4.15 (dd, 1H, S-glyceryl-OCH2b,
JCH2a,CH2b ) 11.8 Hz, JCH,CH2 ) 5.9 Hz), 3.09 (dd, 1H, Cys-CH2a,
JCH2a,CH2b ) 14.0 Hz, JCH,CH2 ) 4.4 Hz), 3.00 (dd, 1H, Cys-CH2b, JCH,CH2
) 5.3 Hz), 2.76 (d, 2H, S-glyceryl-CH2, JCH,CH2 ) 6.6 Hz), 2.38-2.21
(m, 4H, Pal-CH2), 1.70-1.60 (m, 4H, Pal-CH2), 1.48 (s, 9H, tBu-CH3),
t
1.24 (brs, 48H, Pal-CH2), 0.87 (t, 6H, Pal-CH3, JCH2,CH3 ) 6.8 Hz). 13
C
1.47 (s, 9H, Bu-CH3), 1.35-1.15 (m, 7 H, 3x Pal-CH2), 0.91-0.83
(m, 9H, 3x Pal-CH3). 13C NMR (CDCl3) δ 173.3, 172.9, 169.7 (CO),
82.9 (tBu-Cq), 70.4 (S-glyceryl-CH), 63.5 (S-glyceryl-OCH2), 52.4 (Cys-
CHR), 36.5, 35.4, 34.3 34.1, 33.2, 31.9, 29.7, 29.5, 29.4, 29.1 (Cys-
CH2, S-glyceryl-CH2, Pal-CH2), 28.0 (tBu-CH3), 25.6, 24.9, 22.7 (Pal-
CH2), 14.1 (Pal-CH3). LSIMS: m/z ) 989 (100%, [M + Na]+).
S-[2,3-Bis(palmitoyloxy)-(2R)-propyl]-N-palmitoyl-(R)-cysteine
(IR). Compound 7R (600 mg, 0.62 mmol) was dissolved in trifluoro-
acetic acid (6 mL) and stirred for 1 h. The solvent was concentrated in
vacuo, the residue was treated with water (10 mL), and the waxlike
precipitate was washed with cold water (100 mL). Crystallization from
chloroform/light petroleum ether (1:16, v/v, 30 mL) afforded compound
IR (410 mg, 73%) as a white solid: mp ) 66 °C.
NMR (CDCl3, 75 MHz): δ 173.2, 172.9, 169.4, 155.6 (CO), 143.7,
141.2, 127.6, 127.0, 125.0, 119.9 (Fmoc-Ar.), 82.9 (tBu-Cq), 70.1 (S-
glyceryl-CH), 67.1 (Fmoc-CH2), 63.4 (S-glyceryl-OCH2), 54.2 (Cys-
CHR), 47.0 (Fmoc-CH), 35.2 (Cys-CH2), 34.2, 34.0 (Pal-CH2), 33.2
(S-glyceryl-CH2), 31.8, 29.6, 29.4, 29.3, 29.2, 29.0 (Pal-CH2), 27.9 (t-
Bu-CH3), 24.8, 22.6 (Pal-CH2), 14.0 (Pal-CH3). LSIMS: m/z ) 949
(M + Na)+.
N-Fluorenylmethoxycarbonyl-S-[2,3-bis(palmitoyloxy)-(2S)-pro-
pyl]-(R)-cysteine tert-Butyl Ester (6S). The title compound was
prepared according to the same procedure as described for compound
6R/S starting from 5S (1 g, 2.11 mmol). Compound 6S (1.762 g, 88%)
was obtained as a white powder: mp 41-42 °C.
1H NMR (CDCl3) δ 6.58 (d, 1 H, NH, JNH,CH ) 6.3 Hz), 5.21-5.09
(m, 1H, S-glyceryl-CH), 4.74-4.64 (m, 1H, Cys-CHR), 4.37-4.28 (m,
1H, S-glyceryl-OCH2a), 4.10 (dd, 1H, S-glyceryl-OCH2b, JHb,Ha ) 12.0
Hz, JHb,CH ) 6.1 Hz), 3.18-2.97 (m, 2H, Cys-CH2), 2.71 (d, 2H,
S-glyceryl-OCH2, JCH2,CH ) 6.3 Hz), 2.35-2.23 (m, 6H, 3x Pal-C(O)-
CH2), 1.68-1.52 (m, 6H, Pal-CH2), 1.35-1.17 (m, 72H, 3x Pal-CH2),
0.90-0.82 (m, 9H, 3x Pal-CH3). 13C NMR (CDCl3) δ 174.5, 173.6,
172.9 (CO), 70.2 (S-glyceryl-CH), 63.8 (S-glyceryl-OCH2), 52.1 (Cys-
CR), 36.3, 34.3 34.1, 32.9, 31.9, 29.7, 29.6, 29.4, 29.2 25.6, 24.9, 22.7
(Cys-CH2, S-glyceryl-CH2 and Pal-CH2), 14.1 (Pal-CH3). LSIMS: m/z
) 955 (100%, [M + 2Na-H]+).
1H NMR (CDCl3, 300 MHz): δ 7.76 (d, 2H, Fmoc-Ar., JCH,CH
)
7.4 Hz), 7.61 (d, 2H, Fmoc-Ar., JCH,CH ) 7.0 Hz), 7.39 (t, 2H, Fmoc-
Ar.), 7.31 (t, 2H, Fmoc-Ar.), 5.69 (d, 1H, NH, JCH,NH ) 7.7 Hz), 5.20-
5.08 (m, 1H, S-glyceryl-CH), 4.56-4.47 (m, 1H, Cys-CHR), 4.41-
4.32 (m, 1H, S-glyceryl-OCH2a), 4.31 (d, 2H, Fmoc-CH2, JCH,CH2
)
3.7 Hz), 4.23 (t, 1H, Fmoc-CH), 4.13 (dd, 1H, S-glyceryl-OCH2b,
JCH2a,CH2b ) 11.8 Hz, JCH,CH2 ) 5.9 Hz), 3.08 (dd, 1H, Cys-CH2a,
JCH2a,CH2b ) 13.4 Hz, JCH,CH2 ) 4.6 Hz), 3.00 (dd, 1H, Cys-CH2b, JCH,CH2
) 5.1 Hz), 2.76 (d, 2H, S-glyceryl-CH2, JCH,CH2 ) 6.3 Hz), 2.28 (t,
4H, Pal-CH2, JCH2,CH2 ) 7.4 Hz), 1.68-1.51 (m, 4H, Pal-CH2), 1.48
t
(s, 9H, Bu-CH3), 1.24 (brs, 48H, Pal-CH2), 0.87 (t, 6H, Pal-CH3,
S-[2,3-Bis(palmitoyloxy)-(2S)-propyl]-N-palmitoyl-(R)-cysteine (IS).
The title compound was prepared following the procedure described
for compound IR using 7S (470 mg, 0.48 mmol) as the starting material.
Compound IS (370 mg, 84%) was obtained as a white solid: mp )
67-68 °C.
JCH2,CH3 ) 6.1 Hz). 13C NMR (CDCl3, 75 MHz): δ 173.4, 173.0 (CO),
143.8, 141.3, 127.7, 127.1, 125.2, 120.0 (Fmoc-Ar.), 83.1 (tBu-Cq),
70.3 (S-glyceryl-CH), 67.3 (Fmoc-CH2), 63.5 (S-glyceryl-OCH2), 54.4
(Cys-CHR), 47.1 (Fmoc-CH), 35.4 (Cys-CH2), 34.3, 34.1 (Pal-CH2),
33.3 (S-glyceryl-CH2), 32.0, 29.7, 29.5, 29.4, 29.2 (Pal-CH2), 28.0 (t-
Bu-CH3), 24.9, 22.7 (Pal-CH2), 14.2 (Pal-CH3).). LSIMS: m/z ) 949
(M + Na)+.
1H NMR (CDCl3) δ 6.52 (d, 1 H, NH, JNH,CH ) 7.0 Hz), 5.20-5.10
(m, 1H, S-glyceryl-CH), 4.77 (m, 1H, Cys-CHR), 4.37 (dd, 1H,
S-glyceryl-OCH2a, JHa,Hb ) 11.8 Hz, JHa,CH ) 3.3 Hz), 4.09 (dd, 1H,
S-[2,3-Bis(palmitoyloxy)-(2R)-propyl]-N-palmitoyl-(R)-cysteine
tert-Butyl Ester (7R). Compound 6R (881 mg, 0.93 mmol) was
dissolved in DMF/piperidine (10 mL, 1:1, v/v). After being stirred for
2 h, the reaction mixture was concentrated under reduced pressure. The
residue was dissolved in DCM/DMF (5:2, v/v, 10 mL), and palmitic
acid (420 mg, 1.64 mmol), HONB (294 mg, 1.64 mmol), and DIPC
(208 mg, 1.64 mmol) were added. After being stirred for 16 h, the
reaction mixture was diluted with DCM (30 mL), filtered, and washed
with water (3 × 30 mL), aqueous NaHCO3 (5%, 3 × 30 mL), and
water (3 × 30 mL). The combined aqueous layers were extracted with
DCM (3 × 50 mL). The combined organic layers were dried (MgSO4)
and concentrated in Vacuo. The residue was crystallized from chloroform/
MeOH (1:5, v/v, 15 mL) at 0 °C. Compound 7R (880 mg, 97%,) was
isolated as a white solid: mp ) 56-57 °C.
S-glyceryl-OCH2b, JHb,CH ) 6.4 Hz), 3.10 (d, 2H, Cys-CH2, JCH,CH2
)
5.1 Hz), 2.79-2.64 (m, 2H, S-glyceryl-CH2), 2.36-2.25 (m, 6H, 3x
Pal-C(O)CH2), 1.69-1.53 (m, 6H, 3x Pal-CH2), 1.36-1.17 (m, 72 H,
3x Pal-CH2), 0.91-0.83 (m, 9H, 3x Pal-CH3). 13C NMR (CDCl3) δ
174.6 173.7, 173.0 (CO), 70.4 (S-glyceryl-CH), 63.9 (S-glyceryl-OCH2),
52.1 (Cys-CHR), 36.5, 34.5 34.3, 33.0, 32.0, 29.9, 29.7, 29.5, 29.3,
25.7, 25.1, 22.9 (Cys-CH2, S-glyceryl-CH2, Pal-CH2), 14.3 (Pal-CH3).
LSIMS: m/z ) 955 (100%, [M + 2Na-H]+).
N-Fluorenylmethoxycarbonyl-S-[2,3-bis(palmitoyloxy)-(2RS)-
propyl]-(R)-cysteine (8R/S). Compound 6R/S (1 g, 1.05 mmol) was
dissolved in TFA (20 mL), and the mixture was stirred for 1 h and
subsequently concentrated in vacuo. The oily residue was coevaporated
from toluene (3 × 10 mL) and DCM (3 × 10 mL) and finally
lyophilized from tert-butyl alcohol to afford 8R/S (917 mg, 99%) as a
white solid: mp 64-65 °C.
1H NMR (CDCl3, 300 MHz) δ 6.32 (d, 1 H, NH, JNH,2 ) 7.4 Hz),
5.18-5.08 (m, 1H, S-glyceryl-CH), 4.70 (m, 1H, Cys-CHR), 4.32 (dd,
1H, S-glyceryl-OCH2a, JHa,Hb ) 11.8 Hz, JHa,CH ) 3.3 Hz), 4.13 (dd,
1H, S-glyceryl-OCH2b, JHb,CH ) 6.1 Hz), 3.07 (dd, 1H, H-Cys-CH2a,
1H NMR (CDCl3, 300 MHz): two diastereoisomers, δ 7.76 (d, 4H,
Fmoc-Ar., JCH,CH ) 7.4 Hz, R/S), 7.61 (d, 4H, Fmoc-Ar., JCH,CH ) 7.0
Hz, R/S), 7.39 (t, 4H, Fmoc-Ar., R/S), 7.31 (t, 4H, Fmoc-Ar., R/S),
5.73 (d, 2H, NH, JCH,NH ) 7.0 Hz, R/S), 5.26-4.99 (m, 2H, S-glyceryl-
CH, R/S), 4.72-4.59 (m, 2H, Cys-CHR, R/S), 4.45-4.04 (m, 10H,
S-glyceryl-OCH2, Fmoc-CH2, Fmoc-CH, R/S), 3.23-3.02 (m, 4H, Cys-
CH2, R/S), 2.85-2.60 (m, 4H, S-glyceryl-CH2, R/S), 2.38-2.19 (m,
8H, Pal-CH2, R/S), 1.69-1.52 (m, 8H, Pal-CH2, R/S), 1.25 (brs, 96H,
Pal-CH2, R/S), 0.92-0.83 (m, 12H, Pal-CH3, R/S). 13C NMR (CDCl3,
75 MHz): δ 174.1, 173.4, 173.3 (CO), 156.9 (Fmoc-CO), 143.6, 141.1,
JHa,Hb ) 13.8 Hz, JHa,CH ) 4.6 Hz), 2.98 (dd, 1H, Cys-CH2b, J3b,2
)
5.1 Hz), 2.73 (d, 2H, S-glyceryl-CH2a, JHa,CH ) 6.6 Hz), 2.30 (m, 4H,
2 Pal-C(O)CH2), 2.22 (t, 2H, Pal-C(O)CH2, J ) 7.7 Hz), 1.70-1.53
t
(m, 6H, 3 Pal-CH2), 1.47 (s, 9H, Bu-CH3), 1.37-1.16 (m, 72 H, 3
Pal-CH2), 0.91-0.82 (m, 9 H, 3 Pal-CH3); 13C NMR (CDCl3) δ 173.3,
172.9 170.0, (CO), 82.9 (tBu-Cq), 70.3 (S-glyceryl-OCH), 63.5 (S-
glyceryl-OCH2), 52.5 (Cys-CHR), 36.5, 35.2, 34.3 34.1, 33.2, 31.9, 29.7,