Inhibition of MT1-MMP by Hydroxamate Inhibitors
J ournal of Medicinal Chemistry, 1998, Vol. 41, No. 8 1215
for 1.5 h. The reaction mixture was cooled in an ice bath, and
sodium nitrite (2.7 g) was added. After stirring for 30 min
the THF was evaporated and the remaining water layer was
washed with chloroform. The water layer was acidified with2
N HCl to pH 2-3 and extracted with AcOEt, and the extract
was washed with water and brine and dried over MgSO4.
Evaporation of the solvent gave the acid 7b (2.5 g, 98.2%) as
an oil. 7b: 1H NMR (CDCl3) δ 1.43 (9H, s), 1.8-1.9 (1H, m),
1.9-2.1 (1H, m), 2.44 (1H, dd, J ) 5.2, 16.3 Hz), 2.6-2.8 (3H,
m), 2.8-2.9 (1H, m), 7.1-7.3 (5H, m).
m), 7.85-7.95 (1H, m), 8.19 (1H, d, J ) 7.9 Hz), 8.46 (1H, s),
10.11 (1H, s). Anal. (C22H35N3O4) C, H, N.
[4-(N-Hyd r oxya m in o)-2(R)-(3-p h en ylp r op yl)su ccin yl]-
L-ter t-bu tylglycin e-N-m eth yla m id e (1h ): mp 184-185 °C
dec; 1H NMR (DMSO-d6) δ 0.70 (9H, s), 1.10-1.35 (4H, m),
1.84 (1H, dd, J ) 14.5, 6.5 Hz), 2.00 (1H, dd, J ) 14.5, 6.5
Hz), 2.35 (3H, d, J ) 4.5 Hz), 2.55-2.75 (1H, m), 3.97 (1H, d,
J ) 9.5 Hz), 6.90-7.10 (5H, m), 7.39 (1H, br), 7.57 (1H, br),
8.39 (1H, br), 10.08 (1H, bs). Anal. (C20H31N3O4‚1/4H2O) C,
H, N.
(iv) To a solution of L-phenylglycine-N-methylamide (476
mg, 2.9 mmol), HOBT (390 mg), and 7b (800 mg, 2.9 mmol)
in DMF (10 mL) was added 1-[3-(dimethylamino)propyl]-3-
ethylcarbodiimide hydrochloride (556 mg, 2.9 mmol), and the
mixture was stirred at room temperature overnight. The
reaction mixture was diluted with AcOEt, washed with 0.5 N
HCl, water, saturated aqueous NaHCO3 solution, and brine
successively, and dried over MgSO4. After evaporation of the
solvent, the obtained residue was purified by silica gel column
chromatography (AcOEt/n-hexane ) 1/1) to afford 8b (0.84 g,
91.8%) as colorless crystals. 8b: 1H NMR (CDCl3) δ 1.32 (9H,
s), 1.6-1.8 (1H, m), 1.9-2.1 (1H, m), 2.33 (1H, dd, J ) 4.8,
16.4 Hz), 2.5-2.8 (4H, m), 2.81 (3H, d, J ) 4.9 Hz), 5.43 (1H,
d, J ) 6.9 Hz), 5.8-5.9 (1H, m), 7.0-7.4 (1H, m).
(v) A solution of 8b (0.84 g, 1.98 mmol) in 90% aqueous TFA
(3 mL) was stirred under ice cooling for 1 h. After the solvent
was evaporated, the residue was dissolved in chloroform. The
chloroform solution was washed with water and brine, dried
over MgSO4, and evaporated to give 9b (0.58 g, 79.6%) as
colorless crystals. 9b: 1H NMR (DMSO-d6) δ 1.58-1.85 (2H,
m), 2.30 (1H, dd, J ) 5.5, 16.4 Hz), 2.44-2.70 (6H, m), 2.83-
2.97 (1H, m), 5.43 (1H, d, J ) 7.7 Hz), 7.10-7.44 (10H, m),
8.14-8.23 (1H, m), 8.47 (1H, d, J ) 7.8 Hz), 12.0 (1H, bs).
(vi) To a solution of 9b (580 mg, 1.57 mmol), HOBT mono-
hydrate (281 mg, 1.9 mmol), and 1-[3-(dimethylamino)propyl]-
3-ethylcarbodiimide hydrochloride (364 mg, 1.9 mmol) in DMF
(10 mL) were added O-benzylhydroxylamine hydrochloride
(303 mg, 1.9 mmol) and triethylamine (191 mg, 1.9 mmol), and
the mixture was stirred at room temperature overnight. The
reaction mixture was diluted with AcOEt, washed with 0.5 N
HCl, water, saturated aqueous NaHCO3 solution, and brine
successively, and dried over MgSO4. After evaporation of the
solvent, the resultant syrup was purified with silica gel column
chromatography (chloroform/MeOH ) 200/1) to give compound
10b (633 mg, 85%) as a syrup.
(vii) Compound 10b (630 mg, 1.33 mmol) was hydrogenated
in methanol (10 mL) with 10% Pd/C (80 mg) under hydrogen
atmosphere (3 kg/cm2) at room temperature. The catalyst was
removed by filtration, and the filtrate was evaporated. The
residue was crystallized from a mixture of methanol and
AcOEt to give 1b (300 mg, 59%) as colorless crystals.
[4-(N-Hyd r oxya m in o)-2(R)-(3-p h en ylp r op yl)su ccin yl]-
L-va lin e-N-m eth yla m id e (1i): mp 180-185 °C dec; 1H NMR
(DMSO-d6) δ 0.85 (6H, d, J ) 6.6 Hz), 1.3-1.6 (4H, m), 1.9-
2.1 (2H, m), 2.17 (1H, dd, J ) 7.2, 14.5 Hz), 2.5-2.55 (2H, m),
2.58 (3H, d, J ) 4.5 Hz), 2.74-2.77 (1H, m), 4.06-4.12 (1H,
m), 7.0-7.36 (5H, m), 7.64 (2H, br), 8.16 (1H, s), 10.36 (1H,
s). Anal. (C19H29N3O4) C, H, N.
[4-(N-H yd r oxya m in o)-2(R)-isob u t ylsu ccin yl]-L-cyclo-
h exylglycin e-N-m eth yla m id e (1e). (i) To a solution of
L-phenylglycine-N-methylamide7 (1.15 g, 7 mmol) in ethanol
(50 mL) was added rhodium chloride trihydrate (3 g), and the
mixture was stirred at 30 °C for 2 h. Then a solution of sodium
borohydride (2.5 g, 66 mmol) in ethanol (100 mL) was added
to the mixture dropwise for 35 min, and the mixture was
stirred at room temperature for 4 h. After removal of insoluble
material by filtration, the filtrate was evaporated in vacuo.
The obtained residue was dissolved in 1 N HCl, washed with
AcOEt, neutralized by sodium carbonate, and extracted with
AcOEt. The organic layer was dried over MgSO4 and evapo-
rated in vacuo to give L-cyclohexylglycine-N-methylamide as
a crude syrup (700 mg, 58.7%).
(ii) To a solution of L-cyclohexylglycine-N-methylamide (444
mg, 2.6 mmol) and 4-[N-(benzyloxy)amino]-2(R)-isobutylsuc-
cinic acid7 (1; 730 mg, 2.6 mmol) in DMF (20 mL) was added
1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochlo-
ride (750 mg, 3.9 mmol), and the mixture was stirred at room
temperature overnight. The precipitate was collected by
filtration and washed with AcOEt to give compound 4e (725
mg, 64.6%) as colorless crystals. Hydrogenation of 4e in
methanol with 10% Pd/C and recrystallization from AcOEt-
MeOH afforded 1e (290 mg, 50.6%) as colorless crystals. 1e:
mp 215 °C dec; 1H NMR (DMSO-d6) δ 0.79 (3H, d, J ) 6.2
Hz), 0.83 (3H, d, J ) 6.2 Hz), 0.8-1.23 (6H, m), 1.33-1.72
(8H, m), 1.99 (1H, dd, J ) 7.7, 14.3 Hz), 2.14 (1H, dd, J ) 6.4,
14.3 Hz), 2.55 (3H, d, J ) 4.5 Hz), 2.70-2.82 (1H, m), 4.03
(1H, t, J ) 8.1 Hz), 7.73-7.83 (2H, m), 8.71 (1H, s), 10.37 (1H,
s). Anal. (C17H31N3O4) C, H, N.
[4-(N-Hyd r oxya m in o)-2(R)-isobu tyl-3(S)-m eth ylsu cci-
n yl]-L-cycloh exylglycin e-N-m eth yla m id e (2f). (i) To a
solution of benzyl 2-[(benzyloxy)carbonyl]-3(R)-(hydroxycar-
bonyl)-5-methylhexanoate7 (13; 4.4 g, 11 mmol) in DMF (20
mL) were added L-cyclohexylglycine-N-methylamide (1.9 g,
11.2 mmol), HOBT monohydrate (1.5 g), and 1-[3-(dimethy-
lamino)propyl]-3-ethylcarbodiimide hydrochloride (2.1 g, 11
mmol) with ice cooling, and the mixture was stirred at room
temperature overnight. To the reaction mixture was added
0.5 N HCl, and the mixture was extracted with EtOAc (100
mL). The organic layer was washed with water, 0.5 N HCl,
saturated aqueous NaHCO3 solution, and brine successively.
After drying over anhydrous MgSO4, the organic solution was
evaporated in vacuo. The obtained residue was purified with
silica gel column chromatography (chloroform/MeOH ) 20/1)
to give 14f (3.0 g, 50%) as a syrup.
1b: mp 191-194 °C; 1H NMR (DMSO-d6) δ 1.55-1.80 (2H,
m), 2.06 (1H, dd, J ) 7.5, 14.4 Hz), 2.23 (1H, dd, J ) 7.0, 14.4
Hz), 2.40-2.70 (2H, m), 2.59 (3H, d, J ) 4.4 Hz), 2.82-2.98
(1H, m), 5.41 (1H, d, J ) 7.7 Hz), 7.10-7.50 (10H, m), 8.12-
8.22 (1H, m), 8.49 (1H, d, J ) 7.7 Hz), 8.73 (1H, s), 10.40 (1H,
s). Anal. (C21H25N3O4‚0.7H2O) C, H, N.
Compounds 1c,d ,h ,i were obtained in a similar manner of
preparation as for 1b. Their physical data are summarized
as follows.
[4-(N-Hyd r oxya m in o)-2(R)-(3-p h en ylp r op yl)su ccin yl]-
1
L-p h en ylglycin e-N-m eth yla m id e (1c): mp 176-179 °C; H
1
NMR (DMSO-d6) δ 1.30-1.60 (4H, m), 1.99 (1H, dd, J ) 7.2,
14.5 Hz), 2.17 (1H, dd, J ) 7.1, 14.5 Hz), 2.45-2.65 (2H, m),
2.56 (3H, d, J ) 4.4 Hz), 2.80-2.93 (1H, m), 5.39 (1H, d, J )
7.8 Hz), 7.10-7.43 (10H, m), 8.08-8.20 (1H, m), 8.46 (1H, d, J
) 7.8 Hz), 8.71 (1H, s), 10.36 (1H, s). Anal. (C22H27N3O4) C,
H, N.
14f: H NMR (CDCl3) δ 0.75-0.85 (6H, m), 0.8-1.9 (14H,
m), 2.7-2.8 (3H, m), 2.9-3.1 (1H, m), 3.80 (1H, d), 4.1-4.2
(1H, m), 5.0-5.2 (4H, m), 6.1-6.2 (1H, m), 6.5-6.6 (1H, d),
7.2-7.4 (10H, m).
(ii) Compound 14f (3.0 g, 5.4 mmol) was hydrogenated in
EtOH (30 mL) with 10% Pd/C (0.2 g) under hydrogen atmo-
sphere at room temperature for 4 h. After removal of the
catalyst by filtration, piperidine (0.57 g, 6.7 mmol) and 37%
aqueous formaldehyde solution (2.5 mL) were added, and the
mixture was stirred at room temperature for 16 h and then
refluxed for 1 h. The solvents were removed under reduced
[4-(N-Hyd r oxya m in o)-2(R)-n on ylsu ccin yl]-L-p h en ylg-
lycin e-N-m eth yla m id e (1d ): 1H NMR (DMSO-d6) δ 0.63 (3H,
t, J ) 6.8 Hz), 0.9-1.3 (16H, m), 1.74 (1H, dd, J ) 7.5, 14.7
Hz), 1.92 (1H, dd, J ) 7.0, 14.7 Hz), 2.34 (3H, d, J ) 4.5 Hz),
2.50-2.65 (1H, m), 5.15 (1H, d, J ) 7.9 Hz), 7.00-7.20 (5H,