Tight-Binding Inhibitors of Integrin R4â1
J ournal of Medicinal Chemistry, 1999, Vol. 42, No. 5 927
of Boc-LDV(OBn)2 (12.90 g, 20.6 mmol) in THF/H2O (9:1, 30
mL) was added 10% Pd/C (1.0 g), and the reaction mixture
was stirred under H2 (55 psi) for 22 h. The reaction mixture
was filtered through Solka-Floc and concentrated in vacuo to
provide 9.8 g (95%) of Boc-LDV as a white solid: mp 92-93
°C; IR (KBr, cm-1) 3319, 2955, 1725, 1696, 1654, 1625; 1H NMR
(300 MHz, DMSO-d6) δ 8.35 (d, J ) 7.8 Hz, 1H), 7.79 (d, J )
8.6 Hz, 1H), 7.09 (d, J ) 8.4 Hz, 1H), 4.79 (m, 1H), 4.31 (dd,
J ) 8.6, 5.3 Hz, 1H), 4.18 (q, J ) 5.8 Hz, 1H), 2.88 (dd, J )
16.6, 5.9 Hz, 1H), 2.69 (m, 1H), 2.22 (m, 1H), 1.78 (m, 1H),
1.61 (m, 2H), 1.56 (s, 9H), 1.03 (m, 12 H); HRMS m/z (M +
H)+ calcd 446.2502, obsd 446.2509. Anal. Calcd for
Hydrogenolysis of Boc-ILDV(OBn)2 (1.28 g, 1.73 mmol),
using the general procedure, provided Boc-ILDV (860 mg, 89%)
as a white solid: 139-145 °C dec; IR (KBr, cm-1) 3316, 1718,
1678, 1645, 1527; 1H NMR (400 MHz, DMSO-d6) δ 12.4 (br s,
2H), 8.3 (d, J ) 7.2 Hz, 1H), 7.82 (d, J ) 8.2 Hz, 1H), 7.58 (d,
J ) 8.3 Hz, 1H), 6.81 (d, J ) 8.9 Hz, 1H), 4.58 (m, 1H), 4.43
(m, 1H), 4.22 (m, 1H), 4.08 (m, 1H), 2.67 (m, 1H), 2.45 (m,
1H), 2.02 (m, 1H), 1.62 (m, 2H), 1.44 (m, 1H), 1.41 (m, 2H),
1.36 (s, 9H), 1.25 (m, 1H), 0.83-0.67 (m, 18H); MS (EI) 558
(M+); HRMS m/z (M + H)+ calcd 559.3343, obsd 559.3344.
Anal. Calcd for C26H46N4O9‚0.456H2O: C, 55.09; H, 8.34; N
9.88. Found: C, 55.27, H, 8.40; N, 9.54.
C
20H35N3O8: C, 53.92; H, 7.91; N 9.43. Found: C, 54.25, H,
Following the general procedure, hydrolysis of Boc-ILDV
(470.5 mg, 0.84 mmol) provided ILDV‚HCl (350 mg, 84%) as
a white solid: mp 179-182 °C dec; IR (KBr, cm-1) 3327, 2958,
8.22; N, 8.83.
L-Leu cyl-L-r-a sp a r tyl-L-va lin e Hyd r och lor id e (LDV‚
HCl). Acid hydrolysis of Boc-LDV (3.22 g, 7.23 mmol) as above
provided product (2.5 g, 93%) as a white solid: mp 216.6-
216.9 °C; IR (KBr, cm-1) 3260, 2900, 1721, 1657, 1606; 1H NMR
(300 MHz, DMSO-d6) δ 8.90 (d, J ) 7.4 Hz, 1H), 8.30 (br s,
2H), 7.93 (d, J ) 8.2 Hz, 1H), 4.67 (m, 1H), 4.10 (dd, J ) 8.4,
5.7 Hz, 1H), 3.74 (br s, 1H), 2.72 (dd, J ) 16.9, 5.5 Hz, 1H),
2.54 (dd, J ) 16.9, 8.2 Hz, 1H), 2.04 (m, 1H), 1.68 (m, 1H),
1.52 (m, 2H), 0.86 (m, 12H); HRMS m/z (M - Cl)+ calcd
346.1978, obsd 346.1985. Anal. Calcd for C15H27N3O6‚HCl‚
0.21H2O: C, 46.73; H, 7.43; N, 10.99. Found: C, 47.25; H, 7.52;
N, 10.68.
1
1723, 1667, 1527; H NMR (400 MHz, DMSO-d6) δ 8.51 (m,
1H), 8.49 (m, 1H), 8.47 (m, 1H), 7.65 (d, J ) 8.4 Hz, 1H), 4.59
(m, 1H), 4.57 (m, 1H), 4.11 (m, 1H), 3.62 (br s, 3H), 2.67 (m,
1H), 2.47 (m, 1H), 2.02 (m, 1H), 1.78 (m, 1H), 1.64 (m, 1H),
1.45 (m, 3H), 1.10 (m, 1H), 0.87-0.83 (m, 18H); 13C NMR (100
MHz, DMSO-d6) 172.6 (CdO), 171.6 (CdO), 171.5 (CdO),
170.5 (CdO), 167.5 (CdO), 57.05 (CH), 56.27 (CH), 51.0 (CH),
49.4 (CH), 41.3 (CH), 36.2 (CH), 35.6 (CH), 30.1 (CH2), 24.1
(CH2), 23.9(CH2), 23.1 (CH3), 21.8 (CH3), 19.0 (CH3), 17.7 (CH3),
14.5 (CH3), 11.2 (CH3); MS (EI) 459 (M + H)+; HRMS m/z (M
+ H)+, calcd 459.2819, obsd 459.2812. Anal. Calcd for
C
21H38N4O7‚HCl‚0.46H2O; C, 50.12; H, 7.99; N, 11.13. Found:
N-ter t-Bu t yloxyca r b on y-L-leu cyl-L-(r-o-b en zyla sp a r -
ta te) Ben zyl Ester (Boc-LD(OBn )2). Following the general
coupling procedure above, reaction of p-Tos‚Asp(OBn)2 (100.6
g, 207.2 mmol) and Boc-Leu-OSu (71.21 g, 217 mmol) provided,
after recrystallization (EtOAc/hexanes), 98.2 g (90%) of the
product as a white solid: mp 78-79.5 °C; IR (KBr, cm-1) 3433,
C, 50.60; H, 8.18; N, 10.84.
L-Tyr osyl-L-leu cyl-L-r-a sp a r tyl-L-va lin e Hyd r och lor id e
(YLDV‚HCl) (2). The general coupling procedure above utiliz-
ing LDV‚HCl (362 mg, 0.95 mmol) and Boc-Tyr-OSu (339 mg,
0.90 mmol) provided Boc-YLDV (496 mg, 86%) as a white
solid: mp 134-136 °C dec; IR (KBr, cm-1) 3336, 2958, 1718,
1
3023, 2962, 1733, 1650, 1500; H NMR (300 MHz, DMSO-d6)
1
δ 8.36 (d, J ) 7.9 Hz, 1H), 7.34 (m, 10H), 6.86 (d, J ) 8.4 Hz,
1H), 5.06 (s, 4H), 4.74 (dd, J ) 14, 6.7 Hz, 1H), 3.97 (dd, J )
9.2, 5.5 Hz, 1H), 2.91 (dd, J ) 16.6, 6.2 Hz, 1H), 2.78 (dd, J )
16.5, 6.9 Hz, 1H), 1.56 (m, J ) 6.4 Hz, 1H), 1.35 (s, 9H), 1.27
(m, 2H), 0.80 (dd, J ) 6.6, 2.2 Hz, 6H); MS (EI) 427 (M - Boc
+ H)+; HRMS m/z (M+) calcd 549.2577, obsd 549.2563. Anal.
Calcd for C29H38N2O7: C, 66.26; H, 7.22; N, 5.27. Found: C,
66.14, H, 7.27; N, 5.32.
1696, 1678, 1650, 1516; H NMR (400 MHz, DMSO-d6) 12.49
(br s, 1H), 8.35 (d, J ) 8.3 Hz, 1H), 7.89 (d, J ) 8.1 Hz, 1H),
7.60 (d, J ) 8.3 Hz, 1H), 7.01 (d, J ) 7.9 Hz, 2H), 6.84 (d, J )
8.6 Hz, 1H), 6.62 (d, J ) 7.8 Hz, 2H), 4.59 (m, 1H), 4.36 (m,
1H), 4.12 (m, 1H), 4.07 (m, 1H), 2.81 (m, 1H), 2.68 (m, 1H),
2.65 (m, 1H), 2.20 (m, 1H), 1.61 (br s, 1H), 1.43 (br s, 2H),
1.29 (s, 9H), 1.25 (s, 1H), 0.83 (m, 12H); MS (EI) 607 (M -
H)+; HRMS m/z (M + Na)+ calcd 631.2955, obsd 631.2952.
L-Leu cyl-L-(r-o-ben zyla sp a r ta te) Ben zyl Ester Hyd r o-
ch lor id e (LD(OBn )2‚HCl). Removal of the Boc group from
Boc-LD(OBn)2 (95.75 g, 182 mmol) was performed as above to
obtain, after crystallization (CH2Cl2/Et2O), 82.72 g (96%) of the
desired product as a white solid: mp 152-153 °C; IR (KBr,
cm-1) 3448, 2961, 1736, 1709, 1686; 1H NMR (300 MHz,
DMSO-d6) δ 9.22 (d, J ) 7.9 Hz, 1H), 8.41 (br s, 2H), 7.35 (m,
10H), 5.09 (s, 2H), 5.08 (s, 2H), 4.83 (m, 1H), 3.77 (m, 1H),
2.90 (d, J ) 6.4 Hz, 2H), 1.64 (m, J ) 6.8 Hz, 1H), 1.50 (t, J )
7.1 Hz, 2H), 0.82 (dd, J ) 6.4, 3.5 Hz, 6H); MS (EI) 427 (M +
H)+; HRMS m/z (M+) calcd 427.2233, obsd 427.2227. Anal.
Calcd for C24H30N2O5‚HCl: C, 62.26; H, 6.75; N, 6.05. Found:
C, 62.00, H, 6.71; N, 5.96.
Removal of the Boc protecting group from Boc-YLDV (307
mg, 0.50 mmol) as above afforded YLDV‚HCl (244 mg, 90%)
as a white solid: mp 169-171 °C dec; IR (KBr, cm-1) 3371,
3204, 2967, 1730, 1682, 1653, 1518; 1H NMR (300 MHz DMSO-
d6) δ 9.36 (s, 1H), 8.73 (d, J ) 8.3 Hz, 1H), 8.53 (d, J ) 7.5 Hz,
1H), 8.09 (br s, 2H), 7.67 (d, J ) 8.6 Hz, 1H), 7.04 (d, J ) 8.4
Hz, 2H), 6.70 (d, J ) 8.3 Hz 2H), 4.64 (q, J ) 6.2 Hz, 1H),
4.40 (q, J ) 7.1 Hz, 1H), 4.13 (dd, J ) 8.5, 5.3 Hz, 1H), 3.95
(s, 1H), 3.35 (br s, 2H), 3.03 (m, 1H), 2.80 (t, J ) 8.2 Hz, 1H),
2.71 (dd, J ) 17.2, 6.3 Hz, 1H), 2.49 (m, 1H), 2.03 (m, 1H),
1.63 (septet, J ) 6.7 Hz, 1H), 1.46 (t, J ) 6.9 Hz, 2H), 0.85
(overlapping doublets, J ) 6.2, 4.9 Hz, 12H); MS (EI) 509 (M
+ H)+; HRMS m/z (M + Na)+ calcd for C24H36N4O8Na 531.2431,
obsd 531.2423.
L-Leu cyl-L-(r-o-ben zyla sp a r tyl)-L-va lyl-L-p r olin e Ben -
zyl Ester Hyd r och lor id e (LDVP (OBn )2‚HCl). Reiterative
coupling and removal of the Boc group, following the general
procedures described above, provided LDVP(OBn)2‚HCl as a
white solid: mp 175-177.5 °C; IR (KBr, cm-1) 3249, 3182,
3037, 2958, 1741, 1680, 1657, 1618, 1546; 1H NMR (600 MHz,
DMSO-d6) δ 9.17 (d, J ) 7.8 Hz, 1H), 8.49 (br s, 2H), 7.97 (d,
J ) 8.4 Hz, 1H), 7.32 (m, 10H), 5.09 (m, 4H), 4.73 (dd, J )
14.4, 7.2 Hz, 1H), 4.33 (m, 2H), 3.79 (t, J ) 6.9 Hz, 1H), 3.71
(dd, J ) 16.2, 6.6 Hz, 1H), 3.55 (m, 1H), 2.85 (dd, J ) 16.5,
6.3 Hz, 1H), 2.73 (dd, J ) 16.5, 7.3 Hz, 1H), 2.14 (m, 1H), 1.97
(m, 1H), 1.87 (m, 2H), 1.80 (m, 1H), 1.72 (m, 1H), 1.59 (m,
2H), 0.88 (d, J ) 6.6 Hz, 3H), 0.87 (d, J ) 6.6 Hz, 3H), 0.85 (d,
J ) 6.6 Hz, 3H), 0.81 (d, J ) 6.6 Hz, 3H); 13C NMR (150 MHz,
DMSO-d6) δ 171.6 (CdO), 169.8 (CdO), 169.6 (CdO), 169.5
(CdO), 169.1 (CdO), 136.0 (C), 135.9 (C), 128.4 (4CH), 128.01
(CH), 127.97 (CH), 127.90 (2CH), 127.8 (2CH), 65.8 (CH2), 65.7
(CH2), 58.6 (CH), 55.6 (CH), 50.7 (CH), 49.5 (CH), 46.8 (CH2),
40.2 (CH2), 35.8 (CH2), 30.1 (CH), 28.7 (CH2), 24.6 (CH2), 23.6
L-Isoleu cyl-L-leu cyl-L-a sp a r tyl-L-va lin e Hyd r och lor id e
(ILDV‚HCl) (1). To a solution of Boc-Ile (1.42 g, 2.52 mmol)
in DMF (4 mL) were added EDC (584 mg, 3.05 mmol) and
HOBt (555 mg, 4.11 mmol). The reaction mixture was allowed
to stir for 15 min, and LDV(OBn)2‚HCl (1.42 g, 2.52 mmol)
was added followed by Et3N (1.2 mL, 8.6 mmol). After 14 h,
the reaction mixture was poured into 10% citric acid (100 mL).
The precipitate was collected, washed with citric acid (3 × 50
mL), H2O, saturated NaHCO3 (3 × 50 mL), and H2O, and dried
in vacuo to provide Boc-ILDV(OBn)2 (1.86 g, 92%) as a white
solid: mp 175-176 °C; IR (KBr, cm-1) 3282, 2958, 1740, 1690,
1
1645, 1544; H NMR (400 MHz, DMSO-d6) δ 8.29 (d, J ) 7.2
Hz, 1H), 8.01 (d, J ) 8.1 Hz, 1H), 7.83 (d, J ) 8.1 Hz, 1H),
7.31 (s, 10H), 6.82 (d, J ) 8.6 Hz, 1H), 5.06 (m, 4H), 4.68 (m,
1H), 4.45 (m, 1H), 4.18 (m, 1H), 3.77(m, 1H), 3.32 (m, 2H),
2.74 (m, 1H), 2.57 (m, 1H), 2.04 (m, 1H), 1.63 (m, 2H), 1.61
(br s, 1H), 1.39 (s, 9H), 1.05 (m, 1H), 0.84 (m, 18H); MS (EI)
739 (M + H)+; HRMS m/z (M + H)+ calcd 739.4282, obsd
739.4288. Anal. Calcd for C40H58N4O9: C, 65.02; H, 7.91; N
7.58. Found: C, 65.08, H, 7.90; N, 7.54.