1
252 S. H. PARK ET AL.
consisted of KH
sodium salt hydrate (2.163 g). HPLC gradient: 0–
7 min: a linear gradient to 70% A/30% B from 70%
2
PO
4
(1.36 g) and 1-octanesulfonic acid
Synthesis of pyronaridine tetraphosphate (PNDP, 3) from
pyronaridine (PND, 2). 2 (1 eq) synthesized by the above
reaction was mixed with distilled water (10 eq) and
ortho phosphoric acid (7.7 eq) and stirred at room
temperature for 30 min. The mixture was filtered and
washed with distilled water. To the crude product,
methanol (5.3 mL, 3 eq) was added and stirred at
5–108C for 1 h. The mixture was filtered and washed
with acetone (16.3 mL, 20 eq). The solution of crude
product was mixed with 70% ethanol (4 mL, 14 eq) and
ortho phosphoric acid (1.2 mL) and stirred at 60–658C
for 1 h. The mixture was allowed to cool to 10–208C,
filtered and washed with acetone, then dried under
vacuum at 508C to give 95% yield of 3. IR (KBr) n 1551,
1
A/30% B; 17–25 min: a linear gradient to 60% A/40% B
from 70% A/30% B; 25–30 min: a linear gradient to
6
0% A/40% B from 60% A/40% B; 30–31 min: a linear
gradient to 70% A/30% B from 60% A/40% B. The flow
rate was maintained at 1 mL/min and the column
temperature was maintained at 408C.
IR spectra were recorded on a Perkin-Elmer 1420
1
Ratio Recording Spectrophotometer. The H NMR and
1
3
C NMR spectra were recorded on an EA FISON, EA
108, NMR Varian Inc., VNS 600 spectrophotometer.
1
MS were obtained on a Matrix-assisted laser desoption
ionization mass spectrophotometer system, Voyager
TMDE-STR, Proteomics Analyser (Applied Biosystems
Inc.). All chromatographic separations were monitored
by TLC analyses and performed using glass plates
precoated with 0.25 mm 230–400 mesh silica gel
impregnated with a fluorescent indicator (254 nm).
Solvent removal was accomplished with aspirator
pressure using a rotary evaporator.
ꢁ
1 1
1491, 1387, 959 cm
; H NMR (D O): d 1.85 (s, 4 H,
2
CH
CH
2
), 1.99 (s, 4 H, CH
2
), 3.02 (s, 4 H, CH
2
), 3.41 (s, 4 H,
), 7.10 (d,
2
), 3.90 (s, 3 H, OCH
3
), 4.31 (s, 4 H, ArCH
2
1 H, ArH), 7.38 (t, 2 H, ArH), 7.44 (s, 2 H, ArH), 7.78 (s,
1
3
2
1 H, ArH), 8.06 (d, 1 H, ArH); C NMR (D O): d 21.4,
52.1, 52.9, 53.4, 110.7, 117.6, 121.0, 122.1, 123.7,
125.2, 126.4, 129.9, 130.3, 131.6, 138.8, 139.6,
þ
151.3, 153.5, 159.9; MS m/z 518.2 [M -ðH PO4Þ];
3
Anal. Calcd for C29H32ClN O : C 38.27, H 4.87,
5
2
N7.70. Found: C 38.03, H 5.26, N 7.53.
1
4
Synthesis of pyronaridine tetraphosphate (PNDP, 3)
by a classical method
Synthesis of
C-labelled pyronaridine tetrapho-
1
4
sphate ( C-PNDP, 5) by a classical method
1
4
Synthesis of pyronaridine (PND, 2) from 2-methoxy-
A mixture of
C-labelled paraformaldehyde (2.8 g,
0
7
-chloro-10-(4 -hydroxyanilino)-[b]-1,5-naphthyridine
20 eq) and pyrrolidine (6.7 mL, 20 eq) in anhydrous
ethanol (16.7 mL) was refluxed at 50–608C for 1 h. 1
(1.67 g, 1 eq) was added and stirred at 45–558C for 12–
14 h. The mixture was washed with distilled water
(16.7 mL). The residue in methanol (16.7 mL) was
stirred at 5–108C for 2 h and filtered. The residue was
washed with excessive methanol, then the residue was
dissolved in DMSO and dichloromethane (10.2 mL,
v : v ¼ 1 : 1) and stirred at 55–608C for 3 h. The mixture
(
PNC, 1). A mixture of paraformaldehyde (2.8 g, 20 eq)
and pyrrolidine (6.7 mL, 20 eq) in anhydrous ethanol
16.7 mL) was refluxed at 50–608C for 1 h. 1 (1.67 g,
eq) was added and stirred at 45–558C for 12–14 h. The
(
1
mixture was washed with distilled water (16.7 mL). The
residue was dissolved in methanol (16.7 mL) and
stirred at 5–108C for 2 h and filtered. The residue was
washed with excessive methanol, then the residue was
dissolved in dimethyl sulfoxide (DMSO) and dichlor-
omethane (10.2 mL, v : v ¼ 1 : 1) and stirred at 55–608C
for 3 h. The mixture was filtered and washed with
methanol (5.1 mL), then dried to give 40% yield of 2. IR
was filtered and washed with methanol (5.1 mL), then
1
dried to give 36% yield of 5: H NMR (D O): d 2.08 (s, 4
2
H, CH
H, CH
2
), 2.19 (s, 4 H, CH
2
), 3.22 (s, 4 H, CH
2
), 3.63 (s, 4
), 7.24
2
), 4.08 (s, 3 H, OCH
3
), 4.49 (s, 4 H, ArCH
2
(
KBr): n 3300, 2954, 2777, 1618, 1558, 1518, 1493,
(d, 1 H, ArH), 7.52 (t, 2 H, ArH), 7.59 (s, 2 H, ArH), 7.90
(s, 1 H, ArH), 8.20 (d, 1 H, ArH). 4 (1 eq) synthesized by
the above reaction was mixed with distilled water
(10 eq) and ortho phosphoric acid (7.7 eq) and stirred
at room temperature for 30 min. The mixture was
filtered and washed with distilled water. To the crude
5, methanol (5.3 mL, 3 eq) was added and stirred at
5–108C for 1 h. The mixture was filtered and washed
with acetone (16.3 mL, 20 eq). The solution of crude 5
was mixed with 70% ethanol (4 mL, 14 eq) and ortho
phosphoric acid (1.2 mL) and stirred at 60–658C for 1 h.
The mixture was allowed to cool to 10–208C, filtered
1
8
2
466, 1374, 1270, 1068, 1095, 1004, 1000, 927, 866,
ꢁ
1 1
34, 806 cm ; H NMR (CD OD): d 1.82 (t, 8 H, CH ),
3
2
.61 (s, 8 H, CH ), 3.75 (s, 4 H, ArCH ), 4.06 (s, 3 H,
2
2
OCH ), 7.01 (s, 2 H, ArH), 7.03 (s, 1 H, ArH), 7.28 (d, 1
3
H, ArH), 7.65 (d, 2 H, ArH), 7.88 (s, 2 H, ArH), 8.14 (d, 2
1
3
H, ArH); C NMR (CD
3
OD): d 23.2, 53.3, 55.5, 114.6,
1
1
1
19.6, 113.0, 124.5, 124.8, 126.5, 127.2, 128.1,
33.5, 135.3, 138.9, 142.1, 146.1, 148.6, 154.8,
þ
60.5; MS m/z 518.2 [M ]; Anal. Calcd for
C29H32ClN O : C 67.23, H 6.23, N 13.52. Found: C
5
2
6
7.18, H 5.96, N 12.85.
Copyright # 2007 John Wiley & Sons, Ltd.
J Label Compd Radiopharm 2007; 50: 1248–1254
DOI: 10.1002.jlcr