4744 J ournal of Medicinal Chemistry, 2000, Vol. 43, No. 25
Berger et al.
3
3
3
3.53 (q, J (1,4 15) ) 7.1, 2H, H2C(14)), 2.87-2.84 (m, AA′ of a
1.42 (d, J (72, 7) ) 6.9, 3H, H3C(72)), 1.32 (t, J (1,7 16) ) 6.9,
3H, H3C(17)); 13C NMR (100 MHz, CD3OD) δ 206.4 (C(4)), 176.5
(C(1)), 174.7 (C(6)), 157.9 (C(8)), 80.9 (C(9)), 66.1 (C(12)), 51.9
(C(7)), 50.0 (C(5)), 35.5 (C(3)), 32.9 (C(15)), 29.9 (C(13)), 29.0
(C(2), C(10a), C(10b), C(10c)), 26.9 (C(14)), 23.9 (C(16)), 18.7
(C(72)), 14.8 (C(17)); MS (DCI) +) m/z relative intensity 387 (18,
[M]+•), 331 (40), 313 (25), 288 (40), 287 (51), 270 (55), 269 (100),
201 (13), 144 (25) 114 (12), 100 (29), 99 (20); HRMS (ESI) calcd
for C19H34N2O6Na+ 409.2309, found 409.2308.
AA′BB′-system, 2H, H2C(3)), 2.69-2.65 (m, BB′ of a AA′BB′-
system, 2H, H2C(2)), 1.11 (t, 3J (1,4 15) ) 7.1, 3H, H3C(15)); 13
C
NMR (D2O) δ 206.5 (C(4)), 177.3 (C(1)), 70.3 (C(13)), 69.3
(C(14)), 66.8 (C(12)), 49.6 (C(5)), 36.8 (C(3)), 30.0 (C(2)), 16.6
(C(15)); MS (EI) m/z relative intensity 204 (100, [M - Cl]+),
189 (77), 146 (30), 114 (65); HRMS (ESI) calcd for C9H17
NO4+: 204.2448, obs. 204.2444. Anal. calcd for C9H18NO4Cl:
C, 45.10; H, 7.57; N, 5.84. Found: C, 44.45; H, 7.29; N, 5.79.
-
Com p ou n d 3c: 87% yield; mp 25.0-30.0 °C; 1H NMR (400
MHz, D2O) δ 4.20-4.18 (m, 2H, H2C(12)), 4.05 (s, 2H, H2C(5)),
3.70-3.68 (m, 2H, H2C(13)), 3.63-3.61, 3.59-3.56 (m, 2H, m,
2H, H2C(14), H2C(15)), 3.51 (q, 3J (1,6 17) ) 7.1, 2H, H2C(16)),
2.87-2.83 (m, AA′ of AA′BB′-system, 2H, H2C(3)), 2.68-2.65
(m, BB′ of AA′BB′-system, 2H, H2C(2)), 1.11 (t, 3J (1,6 17) )
7.1, 3H, H3C(17)); 13C NMR (100 MHz, D2O) δ 206.6 (C(4)),
177.3 (C(1)), 72.2, 71.5 (C(14), (C(15)), 71.0 (C(13)), 69.2 (C(16)),
66.7 (C(12)), 49.7 (C(5)), 36.9 (C(3)), 30.0 (C(2)), 16.7 (C(17));
MS (EI) m/z relative intensity 248 (46, [M - Cl]+), 117 (25),
99 (68), 86 (45), 72 (100); HRMS (ESI) calcd for C11H22NO5+:
248.1491, obs. 248.1495. Anal. calcd for C11H22NO5Cl: C, 46.56;
H, 7.81; N, 4.94. Found: C, 44.93; H, 7.18; N, 4.93.
Com p ou n d 6c: 75% yield; H NMR (400 MHz, CDCl3) δ
1
7.30-7.17 (m, 5H, HC(74), HC(74′), HC(75), HC(75′), HC(76)),
6.65 (sbr, 1H, NH-H2C(5)), 5.00 (sbr, 1H, NH-HC(7)), 4.41 (sbr,
1H, HC(7)), 4.20-4.04 (m, 2H, H2C(5)), 3.66 (s, 3H, H3C(12)),
3.13-2.99 (m, 2H, H2C(72)), 2.70-2.66 (m, AA′ of an AA′BB′
system, 2H, H2C(3)), 2.64-2.59 (m, BB′ of an AA′BB′ system,
2H, H2C(2)), 1.38 (s, 9H, H3C(10a), H3C(10b), H3C(10c)); 13C
NMR (100 MHz, CDCl3) δ 203.2 (C(4)), 172.7 (C(1)), 171.4
(C(6)), 155.3 (C(8)), 136.5 (C(73)), 129.2, 128.6 (C(7,4 74′, 7,5 75′)),
(C(7,4 74′)), 126.9 (C(76)), 80.2 (C(9)), 55.6 (C(7)), 51.9 (C(12)),
49.0 (C(5)), 38.4 (C(72)), 34.4 (C(3)), 28.2 (C(10a), C(10b), C(10c)),
27.5 (C(2)); MS (APCI) +) m/z relative intensity 394 (23, [M +
H]+), 393 (98, [M]+•), 337 (14), 293 (13), 275, 261, 247, 243,
215; HRMS calcd for C20H28N2O6Na+ 415.1840, found 415.1838.
Anal. (C20H28N2O6) C, H, N.
Com p ou n d 3d : 90% yield; 1H NMR (400 MHz, D2O) δ
4.31-4.28 (m, 2H, H2C(12)), 4.15 (s, 2H, H2C(5)), 3.79-3.77
(m, 2H, H2C(13)), 3.75-3.72, 3.73, 3.70-3.67 (m, 2H, ′s′, 4H,
Com p ou n d 6d : 71% yield; 1H NMR (400 MHz, CD3OD) δ
4.23-4.09 (m, 3H, H2C(5), HC(7)), 3.74 (s, 3H, H3C(12)), 3.15-
3.11 (m, 2H, H2C(75)), 2.88-2.84 (m, AA′ of a AA′BB′-system,
2H, H2C(3)), 2.70-2.66 (m, BB′ of a AA′BB′-system, 2H, H2C-
(2)), 1.92-1.84 (m, 1H, HC(72a)), 1.76-1.67 (m, 1H, HC(72b)),
1.54 (s, 18H, H3C(78a), H3C(78b), H3C(78c), H3C(10a), H3C(10b),
H3C(10c)), 1.64-1.40 (m, 4H, H2C(73), H2C(74)); 13C NMR (100
MHz, CD3OD) δ 206.4 (C(4)), 175.9 (C(1)), 175.1 (C(6)), 158.8,
158.2 (C(76), C(8)), 80.9, 80.1 (C(77), C(9)), 56.3 (C(7)), 52.5
(C(12)), 49.9 (C(5)), 41.3 (C(75)), 35.5 (C(3)), 33.2 (C(72)), 30.9
(s, C(74)), 29.1 (C(78a), C(78b), C(78c) or C(10a), C(10b), C(10c)),
29.0 (C(10a), C(10b), C(10c) or C(78a), C(78b), C(78c)), 28.7 (C(2)),
24.4 (C(73)); MS (ESI+) m/z relative intensity 475 (23, [M +
H]+), 474 (100, [M]+•), 418 (8), 374 (11), 318 (3), 300; HRMS
(ESI) calcd for C22H39N3O8Na+ 496.2629, found 496.2631. Anal.
calcd for C22H39N2O8: C, 55.80; H, 8.30; N, 8.87. Found: C,
55.27; H, 8.40; N, 8.56.
m, 2H, H2C(17), H2C(16), H2C(15), H2C(14)), 3.64 (q, J (1,8 19)
3
) 7.0, 2H, H2C(18)), 2.95-2.92 (m, AA′ of a AA′BB′-system,
2H, H2C(3)), 2.82-2.79 (m, BB′ of a AA′BB′-system, 2H, H2C-
(2)), 1.28 (t, 3J (1,9 18) ) 7.1, 3H, H3C(19)); 13C NMR (100 MHz,
D2O) δ 203.5 (C(2)), 174.0 (C(1)), 71.8, 71.7, 71.1 (C(14)-C(17)),
70.3 (C(13)), 67.8 (C(18)), 65.2 (C(12)), 48.6 (C(5)), 35.6 (C(3)),
29.0 (C(2)), 15.7 (C(19)); MS (ESI+) m/z relative intensity 315
(25, [M - HCl + Na]+), 293 (100, [M - Cl]+), 201 (27), 196
(56), 179 (99), 149 (37); HRMS (ESI) calcd for C13H26NO6
292.1755, obs. 292.1751.
+
:
Gen er a l P r oced u r es for th e P r ep a r a tion of th e P ep -
tid e An a logu es 7a -e via Cou p lin g of 5-Am in olevu lin ic
Acid Ester s w ith BOC-P r otected Am in o Acid s 4a -d
F ollow ed by Acid In d u ced Dep r otection of th e BOC-
Gr ou p . Cou p lin g. A total of 1 mmol of BOC-amino acids (4a -
d ) (Novabiochem) dissolved in 8 mL of DMF was activated
during 45 min by addition of 0.82 g (6.1 mmol) of N-
hydroxybenzotriazole (HOBt, Novabiochem) and 1.16 g (6.1
mmol) of N-(3-dimethylaminoprpyl)-N′-ethylcarbodiimide HCl
(EDC, Fluka). A solution of 5.5 mmol of ALA-methyl (5a ) or
ALA-hexyl (5b) esters in 6 mL of DMF was added for 10 min,
then 0.77 mL (5.5 mmol) of triethylamine (NEt3, Fluka) was
added. After 12 h stirring at room temperature, the DMF was
distilled in a Kugelrohr oven (50 °C/0.5 mbar) and the crude
material was extracted with 2 × 100 mL of ethyl acetate and
washed sequentially with 75 mL of 1 M citric acid, NaHCO3
10%, and NaCl saturated water. The solution was applied to
a silica chromatography column (50 g silica gel (Fluka), eluent:
ethyl acetate:hexane, 1:3 to 5:1). The pure products were
obtained as solids following evaporation of the solvent.
1
Com p ou n d 6e: 73% yield; H NMR (400 MHz, CDCl3) δ
3
3
7.16 (t, J (5, NH) ) 4.8, 1H, NH-H2C(5)), 5.68 (d, J (7, NH) )
8.2, 1H, NH-HC(7)), 4.46-4.43 (m, 1H, HC(7)), 4.09 (dxt, 3J (5,
NH) ) 4.6, J (3, 5) ) 2.2, 2H, H2C(5)), 3.59 (s, 3H, H3C(12)),
4
2.79-2.73 (m, 1H, HC(72a)), 2.69-2.65 (m, AA′ of a AA′BB′-
system, 2H, H2C(3)), 2.61-2.54 (m, 3H, H2C(2), HC(72b)), 1.38
(s, 9H, H3C(75a), H3C(75b), H3C(75c)), 1.36 (s, 9H, H3C(10a), H3C-
(10b), H3C(10c)); 13C NMR (100 MHz, CDCl3) δ 203.2 (C(4)),
172.6 (C(1)), 171.0 (C(6)), 170.7 (C(73)), 155.3 (C(8)), 81.4
(C(74)), 80.1 (C(9)), 51.7 (C(12)), 50.6 (C(7)), 49.0 (C(5)), 37.2
(C(72)), 34.2 (C(3)), 28.1, 27.8 (C(75a), C(75b), C(75c)), C(10a),
C(10b), C(10c)), 27.4 (C(2)); MS (ESI) 439(21, [M + Na]+), 418
(20, [M + H]+), 417 (100, [M]+•), 416 (11), 361 (16); HRMS (ESI)
calcd for C19H32N2O8Na+ 439.2053, found 439.2051.
1
Com p ou n d 6a : 72% yield; H NMR (400 MHz, CDCl3) δ
P r oced u r e for th e Dep r otection of th e N-Ter m in a l
Am in o Acid F u n ction . A total of 0.3 mmol of protected amino
acid-ALA derivatives was dissolved in 3 mL (39 mmol) of TFA
under argon atmosphere. After the solution was stirred for 1
h at room temperature, TFA was evaporated under high
vacuum. The products were obtained in good purity and
characterized without further purification.
7.07 (sbr, 1H, NH-H2C(5)), 5.30 (sbr, 1H, NH-HC(7)), 4.19-
4.16 (m, 1H, HC(7)), 4.11 (d, 3J (5, NH) ) 5.0, 2H, H2C(5)), 3.60
(s, 3H, H3C(12)), 2.71-2.67 (m, AA′ of a AA′BB′-system, 2H,
H2C(3)), 2.59-2.55 (m, BB′ of a AA′BB′-system, 2H, H2C(2)),
1.37 (s, 9H, H3C(10a), H3C(10b), H3C(10c)), 1.30 (d, J (7, 72) )
3
7.1, 3H, H3C(72)); 13C NMR (100 MHz, CDCl3) δ 203.8 (C(4)),
173.0, 172.7 (C(1), C(6)), 155.3 (C(8)), 80 (C(9)), 51.7 (C(12)),
49.9 (C(7)), 48.9 (C(5)), 34.3 (C(3)), 28.1 (C(10a), C(10b), C(10c)),
27.4 (C(2)), 18.4 (C(72)); MS (EI) +) m/z relative intensity 317
(29, [M + H]+), 261 (53), 217 (16), 145 (31), 144 (100), 140 (26),
115 (68), 88 (80), 87 (20), 70 (20); HRMS calcd for C14H24N2O6-
Na+ 339.1526, found 339.1525. Anal. (C14H24N2O6) C, H, N.
Com p ou n d 7a : 98% yield; 1H NMR (400 MHz, DMSO-d6)
δ 8.81 (t, 3J (5, NH) ) 5.6, 1H, NH-H2C(5)), 8.26 (sbr, 3H,
H3N+), 4.24 (dxd, J (5, NH) ) 5.7, J (5a, 5b) ) 12.7, 1H, HC-
(5a)), 4.16 (dxd, 3J (5, NH) ) 5.5, 2J (5a, 5b) ) 12.9, 1H, HC(5b)),
4.07-4.00 (m, 1H, HC(7)), 3.68 (s, 3H, H3C(12)), 2.86-2.82 (m,
3
2
AA′ of a AA′BB′-system, 2H, H2C(3)), 2.62 (m, BB′ of a AA′BB′-
1
3
Com p ou n d 6b: (65% yield); H NMR (400 MHz, CD3OD)
system, 2H, H2C(2)), 1.49 (d, J (7, 72) ) 7.0, 3H, H3C(72)); 13
C
δ 4.22-4.13 (m, 3H, H2C(5), HC(7)), 4.15 (t, 3J (12, 13) ) 6.7,
2H, H2C(12)), 2.87-2.84 (m, AA′ of a AA′BB′, 2H, H2C(3)),
2.69-2.66 (m, BB′ of a AA′BB′, 2H, H2C(2)), 1.71 (quint., 3J (13,
14) ) 3J (13, 12) ) 6.7, 2H, H2C(13)), 1.53 (s, 9H, H3C(10a), H3C-
(10b), H3C(10c)), 1.47-1.37 (m, 6H, H2C(14), H2C(15), H2C(16)),
NMR (100 MHz, DMSO-d6) δ 204.9 (C(4)), 172.9 (C(1)), 170.2
(C(6)), 51.6 (C(12)), 48.5 (C(7)), 48.4 (C(5)), 34.2 (C(3)), 27.4
(C(2)), 17.5 (C(72)); MS (ESI) m/z relative intensity 239 (4, [M
+ Na]+), 217 (100, [M + H]+), 199 (38), 171, 167, 146 (18);
HRMS (ESI) calcd for [C9H17N2O4]+ 217.1183, found 217.1191.