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8. Li, Z.; Jiang, H.; Xie, W.; Zhang, Z.; Smrcka, A. V.; Wu,
D. Science 2000, 287, 1046.
9. Ornstein, P.; Bleisch, T. J.; Arnold, M. B.; Wright, R. A.;
Johnson, B. G.; Schoepp, D. D. J. Med. Chem. 1998, 41,
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10. Sasaki, T.; Irie-Sasaki, J.; Jones, R. G.; Oliveria-dos-
Santos, A. J.; Stanford, W. L.; Bolon, B.; Wakeham, A.;
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11. Stein, R. C. Endocr. Relat. Cancer 2001, 8, 237.
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activity in the superoxide inhibition assay except for 10d
(R = 4-Cl, SUOX IC50 = 670 nM). To further explore
the SAR, a series of phenethyl analogs were synthesized
in a similar manner to the benzoic acids. Commercially
available phenyl-acetic acids (5) were reduced to the cor-
responding alcohols (6, n = 1) using BH3–SMe2 and the
resultant alcohols were then converted to the primary
phenethyl iodides (7j–w).9,18 The primary iodides were
preferred over the primary bromides in the phase trans-
fer alkylation of the template (4), affording modest
yields of the N-substituted benzoxazine–aldehyde tem-
plates (8j–w).19 Knoevenagel condensation of rhodanine
(9) with aldehydes (8j–w) provided the target com-
pounds (10j–w).5,20 Table 1 summarizes the SAR around
the phenethyl analogs. Various substitution of the phen-
yl ring gave potent analogs for PI3Kc with limited SAR.
The only analog that exhibited a loss of activity was the
4-t-butyl analog, 10r (IC50c = 39.0 nM). Para substitu-
tion of the phenyl ring gave potent analogs in this series,
especially 10o (R = 4-Br, IC50c = 2.00 nM) and 10s
(R = 4-CF3, IC50c = 2.00 nM). 2,4- and 3,4-substitution
of the phenyl ring also gave potent PI3Kc inhibition, for
instance 10q (R = 3,4-Cl, IC50c = 4.00 nM) and 10t
(R = 2,4-Cl, IC50c = 5.00 nM). Subsequent testing in
cellular assays of superoxide inhibition showed that para
substitution afforded good potency. Compound 10q
(R = 3,4-Cl, SUOX IC50 = 285 nM) was the most potent
compound in cell based assays. A few analogs were test-
ed in the mouse peritonitis model with three of them
(10m, 10n, and 10p) showing promising activity, while
others exhibited insignificant inhibition. This series will
be further evaluated by extending the alkyl linker and
with various substitution of the phenyl ring.
13. Vlahos, C. J.; Matter, W. F.; Hui, K. Y.; Brown, R. F.
J. Biol. Chem. 1994, 269, 5241.
14. Wymann, M. P.; Zvelebil, M.; Laffargue, M. Trends
Pharmacol. Sci. 2003, 24, 366.
15. Preparation of intermediate 1: To a solution of 4-hydroxy-
3-nitrobenzaldehyde (10.0 g, 59.8 mmol) in tetrahydrofu-
ran (600 mL) and DMF (240 mL) were added dry sodium
hydride (1.58 g, 65.82 mmol) and ethyl bromoacetate
(7.30 mL, 65.82 mmol). The reaction mixture was refluxed
for 24 h. The reaction was then concentrated and diluted
with ethyl acetate (500 mL) and acidified to pH 2 with 1 N
HCl. The organic layer was then washed with saturated
sodium bicarbonate (2· 200 mL), sodium chloride (2·
200 mL), dried over magnesium sulfate, filtered, and
concentrated under reduced pressure to yield a dark red
oil. The oil was used in the next step without purification.
1H NMR (d6-DMSO) d 1.18 (t, 3H), 4.15 (q, 2H), 5.14 (s,
2H), 7.49 (d, 1H), 8.11 (dd, 1H), 8.41 (s, 1H), 9.93 (s, 1H).
MS: MÀ1 = 252 Da.
16. Preparation of intermediate 2: To a solution of interme-
diate 1 (6.40 g, 1.67 mmol) in methanol (100 mL) was
added Raney nickel (3.0 g). The reaction was then
pressurized under an atmosphere of hydrogen to 48 psi
for 23 h. The solution was then filtered through a pad of
Celite. The Celite cake was washed with methanol
(200 mL) and concentrated under reduced pressure to
In conclusion, a series of benzoxazine–rhodanines have
been developed as potent inhibitors of PI3Kc in enzy-
matic and cell based assays. The most promising com-
pounds were subsequently profiled in vivo in an
aseptic peritonitis model of inflammatory cell migration
and showed significant inhibition of neutrophil and
monocyte migration to the infected area.
1
yield a brown solid. H NMR (d6-DMSO) d 4.36 (s, 2H),
À1
4.50 (s, 2H), 5.12 (s, 1H), 6.62–6.86 (m, 3H). MS: M
178 Da.
=
17. Preparation of intermediate 3: To a solution of interme-
diate 2 (2.0 g, 11.2 mmol) in dichloromethane (80 mL) at
room temperature was added pyridinium dichromate
(6.31 g, 16.8 mmol). The reaction mixture was stirred for
24 h. The reaction mixture was then filtered through a pad
of Celite. The Celite cake was washed with ethyl ether
(100 mL) and ethyl acetate (100 mL). The solution was
then concentrated under reduced pressure to yield a dark
References and notes
1
red solid. H NMR (d6- DMSO) d 4.67 (s, 2H), 7.09 (d,
1H), 7.33 (s, 1H), 7.49 (d, 1H), 9.79 (s, 1H). MS:
1. Bi, L.; Okabe, I.; Bernard, D.; Wynshaw-Boris, A.;
Nussbaum, R. J. Biol. Chem. 1999, 274, 10963.
2. Braselmann, S.; Palmer, T. M.; Cook, S. J. Curr. Biol.
1997, 7, R470.
3. Cantley, L. C. Science 2002, 296, 1655.
4. Chiosis, G.; Rosen, N.; Sepp-Lorenzino, L. Bioorg. Med.
Chem. Lett. 2001, 11, 909.
5. Hanefeld, W.; Schlitzer, M.; Debski, N.; Euler, H.
Heteroat. Chem. 1996, 33, 1143.
6. Hirsch, E.; Katanaev, V. L.; Garlanda, C.; Azzolino,
O.; Pirola, L.; Silengo, L.; Sozzani, S.; Mantovani,
A.; Altruda, F.; Wymann, M. P. Science 2000, 287,
1049.
7. Leopoldt, D.; Hanck, T.; Exner, T.; Maier, U.; Wetzker,
R.; Nurnberg, B. Biol. Chem. 1998, 273, 7024; Stephens, L.
R.; Eguinoa, A.; Erdjument-Bromage, H.; Lui, M.;
Cooke, F.; Coadwell, J.; Smrcka, A. S.; Thelen, M.;
Cadwallader, K.; Tempst, P.; Hawkins, P. T. Cell 1997,
89, 105.
M
À1 = 175 Da.
18. Preparation of intermediate 7: To a room temperature
solution of PPh3 (5.78 g, 22.0 mmol) and I2 (5.59 g,
22.0 mmol) in dry CH2Cl2 (100 mL) after 10 min of
stirring was added imidazole (2.50 g, 36.7). Following
another 10 min of stirring 2-m-tolyl-ethanol (2.00 g,
14.7 mmol) was added and the reaction was monitored
by TLC. The reaction was quenched with aqueous sodium
metabisulfite and then extracted with Et2O (3· 30 mL).
The organics were dried over MgSO4, filtered, and
concentrated down under reduced pressure. The product
was chromatographed with EtOAc/hexane (1:3) to yield
2.70 g of product. 1H NMR (d6-DMSO) d 2.20 (s, 3H),
3.00–3.15 (m, 2H), 3.40–3.45 (m, 2H), 6.95–7.10 (m, 3H),
7.15–7.20 (m, 1H) ppm.
19. Preparation of intermediate 8: To a suspension of
benzoxazine (0.500 g, 2.82 mmol) and K2CO3 (0.971 g,