2708 J ournal of Medicinal Chemistry, 2004, Vol. 47, No. 10
Brief Articles
Et2O to provide the title compound (5.1 g, 91%), which was
identical with an authentic sample.8
3, 6, and I were tested at five concentrations. The log(dose)-
response curves were then constructed from the inhibitory
data, and IC50 values were calculated by least-squares analysis
of the linear portions of log(dose)-response curves (0.880 <
r2 < 0.993). All experiments were performed in triplicate.
Results are shown in Table 1.
2,6-Diflu or o-4-pyr r ol-1-ylph en ol (3). A mixture of 4-amino-
2,6-difluorophenol hydrochloride (2) (1.11 g, 6.13 mmol), 2,5-
dimethoxytetrahydrofuran (1.30 g, 9.85 mmol), and 4-chloro-
pyridine (1.09 g, 9.6 mmol) in dioxane (120 mL) was refluxed
under atmosphere and with vigorous stirring for 3 h. The
mixture was cooled to room temperature and concentrated
under reduced pressure. Most of the residue was dissolved in
CH2Cl2 by the gradual addition of several portions of this
solvent, dried over anhydrous Na2SO4, and concentrated under
reduced pressure. The residue was flash-chromatographed
with petroleum ether/EtOAc (10:1) to provide the title com-
pound (1.11 g, 86%). An analytical sample was prepared by
recrystallization from petroleum ether: mp 53-55 °C; IR
In Vitr o P r otein Glyca tion Assa y. The assay was per-
formed as previously described.9,12b,21 It involved incubation
of bovine serum albumin (BSA, fraction V, essentially fatty
acid free) with fructose for 28 days. The test compounds 6 and
I as well as trolox (reference) were dissolved in water in the
form of their potassium salts. Results are shown in Table 2.
Ack n ow led gm en t. This work was supported by
Grant PENED99ED427 from the General Secretariat
of Research and Technology of Greece (V.J .D. and I.N.)
and from the Public Benefit Foundation Alexander S.
Onassis (C.Z.). Special thanks are addressed to Dr.
Najlaa Zaher, Dr. Antonis Gavalas, Costas Anagnostou
(M.Sc.), and Edouard Mamadou for technical assistance
at the early stages of this work.
(Nujol) 3350 cm-1 1H NMR (CDCl3) δ 6.25-6.45 (m, 3H,
;
pyrrolyl-3,4H and phenyl-OH), 6.85-7.05 (m, 4H, pyrrolyl-
2,5H and phenyl-H). Anal. (C10H7F2NO) C, H, N.
Ben zoic Acid 2,6-Diflu or o-4-p yr r ol-1-ylp h en yl E st er
(4). To a well stirred mixture of 2,6-difluoro-4-pyrrol-1-ylphenol
(3) (0.98 g, 5 mmol), tetrabutylammonium hydrogen sulfate
(0.1 g, 0.3 mmol), and pulverized NaOH (0.5 g) in dioxane (12.5
mL), benzoyl chloride (0.98 g, 7 mmol) in dioxane (5 mL) was
added dropwise over a period of 0.5 h at room temperature
and under a nitrogen atmosphere. The mixture was filtered
and washed with dioxane (3 × 10 mL), and the combined
filtrates were evaporated under reduced pressure. The solid
residue was recrystallized from CH2Cl2/petroleum ether to
provide the title compound (1.13 g, 75%): mp 124-125 °C; IR
Refer en ces
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(Nujol) 1750 cm-1 1H NMR (CDCl3) δ 6.35-6.50 (m, 2H,
;
pyrrolyl-3,4H), 6.95-7.30 (m, 5H, pyrrolyl-2,5H and phenyl-
H), 7.50-7.75 (m, 2H, phenyl-H), 8.15-8.35 (m, 2H, phenyl-
H). Anal. (C17H11F2NO2) C, H, N.
[1-(3,5-Diflu or o-4-h ydr oxyph en yl)-1H-pyr r ol-3-yl]ph en -
ylm eth a n on e (6). To a stirred suspension of AlCl3 (0.8 g, 6
mmol) in ethylene dichloride at room temperature and under
a nitrogen atmosphere, benzoyl chloride (0.79 g, 5.6 mmol) was
slowly added, and the resulting mixture was stirred for 10 min.
A solution of benzoic acid 2,6-difluoro-4-pyrrol-1-ylphenyl ester
(4) (1.5 g, 5 mmol) in 1,2-dichloroethane (5 mL) was then
added, and the mixture was stirred for 90 min. The reaction
mixture was poured onto stirred H2O/ice (∼40 mL), the organic
layer was collected, and the aqueous layer was extracted with
CHCl3 (2 × 20 mL). The combined organic phases were washed
with saturated NaCl solution, dried over Na2SO4, and evapo-
rated under reduced pressure. The residue was dissolved in
dioxane (20 mL), to this a 5% solution of NaOH was added,
and the reaction mixture was vigorously stirred at room
temperature and under a nitrogen atmosphere for 24 h. The
reaction mixture was concentrated under reduced pressure to
half of its volume, H2O (20 mL) was added, the mixture was
cooled (ice bath) and acidified with concentrated HCl solution,
and the product was extracted with EtOAc (2 × 50 mL). The
combined organic extracts were washed with saturated NaCl
solution, dried over Na2SO4, and evaporated under reduced
pressure. H2O (50 mL) was added to the residue, the mixture
was basified with the dropwise addition of triethylamine under
vigorous stirring, and the product was extracted with EtOAc
(3 × 50 mL). The combined organic extracts were washed with
saturated NaCl solution, dried over Na2SO4, and evaporated
under reduced pressure. The residue was flash-chromato-
graphed with petroleum ether/EtOAc (5:1) to provide the title
compound (0.82 g, 55%). An analytical sample was prepared
by recrystallization fron toluene/petroleum ether: mp 186 °C;
IR (Nujol) 3100, 1600 cm-1; 1H NMR (CDCl3/DMSO-d6) δ 6.75-
6.85 (m, 1H, pyrrolyl-4H), 6.90-7.10 (m, 3H, pyrrolyl-2,5H and
phenyl-OH), 7.40-7.65 (m, 5H, phenyl-H), 7.75-7.95 (m, 2H,
phenyl-H). Anal. (C17H11F2NO2) C, H, N.
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In Vitr o Ald ose Red u cta se En zym e Assa y. The test
compounds 3, 6, and I as well as sorbinil (C11H9FN2O3,
reference) were dissolved in 0.2 M NaHCO3. Lenses were
quickly removed from Fischer-344 rats of both sexes following
euthanasia, and enzyme preparation and assay were per-
formed as previously described.12b,20 To generate IC50 values,