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A.M. Piloto et al. / Journal of Photochemistry and Photobiology A: Chemistry 299 (2015) 44–53
2.5. Synthesis of (acridin-9-yl) methyl butyrate, 8
To solution of 9-(bromomethyl) acridine
acetate/light petroleum as eluent. Compound 10 was obtained as
oil (0.257 g, 71%). Rf = 0.28 (ethyl acetate/light petroleum, 1:4). 1H
NMR (400 MHz, CDCl3): dH = 0.99 (t, J = 7.2 Hz, 3H, CH3—CH2—CH2),
1.69–1.78 (m, 2H, CH3—CH2—CH2), 2.45 (t, J = 7.2 Hz, 2H, CH3—
CH2—CH2), 3.90 (s, 3H, OCH3), 5.52 (d, J = 1.2 Hz, 2H, CH2), 6.58 (t,
J = 1.2 Hz, 1H, H-2), 7.14 (d, J = 2.4 Hz, 1H, H-7), 7.22 (dd, J = 9.2 and
2.8 Hz, 1H, H-9), 7.31 (d, J = 9.2 Hz, 1H, H-10), 7.78 (d, J = 8.8 Hz, 1H,
H-5), 7.87 (d, J = 9.6 Hz, 1H, H-6). 13C NMR (100.6 MHz, CDCl3):
dC = 13.54 (CH3—CH2—CH2), 18.22 (CH3—CH2—CH2), 35.82 (CH3—
CH2—CH2), 55.22 (OCH3), 63.78 (CH2), 108.43 (C-7), 112.43 (C-4b),
112.72 (C-2),117.89 (C-10),119.86 (C-9),123.50 (C-6b),125.86 (C-6),
132.62 (C-5), 132.66 (C-1), 150.91 (C-4a), 153.14 (C-6a), 156.82
a
2 (0.038 g,
1.39 ꢁ10ꢂ4 mol) in dry DMF (3 mL) potassium fluoride (0.073 g,
4.17 ꢁ10ꢂ4 mol) and butyric acid (0.014 mL, 1.52 ꢁ10ꢂ4 mol) were
added. The reaction was followed by TLC (ethyl acetate/light
petroleum, 1:1), and stirred at room temperature for 15 h. The
solvent was removed by rotary evaporation under reduced
pressure and the crude residue was purified by column chroma-
tography using ethyl acetate/light petroleum, mixtures of increas-
ing polarity as eluent. Compound 8 was obtained as a brown oily
solid (0.027 g, 69%). Rf = 0.48 (ethyl acetate/light petroleum,1:1).1H
NMR (400 MHz, CDCl3): dH = 0.89 (t, J = 7.2 Hz, 3H, CH3—CH2—CH2),
1.63 (sext, J = 7.2 Hz, 2H, CH3—CH2—CH2), 2.32 (t, J = 7.2 Hz, 2H,
CH3—CH2—CH2), 6.12 (s, 2H, CH2), 7.62 (dt, J = 7.6 and 1.2 Hz, 2H,
H-2 and H-7), 7.79 (dt, J = 7.8 and 1.2 Hz, 2H, H-3 and H-6), 8.28 (d,
J = 8.6 Hz, 2H, H-4 and H-5), 8.34 (d, J = 9.0 Hz, 2H, H-1 and H-8).
13C NMR (100.6 MHz, CDCl3): dC = 13.54 (CH3—CH2—CH2), 18.34
(CH3—CH2—CH2), 35.96 (CH3—CH2—CH2), 57.31 (CH2), 124.03
(C-1 and C-8), 125.32 (C-8a and C-9a), 126.68 (C-2 and C-7),
129.97 (C-4 and C-5), 130.08 (C-3 and C-6), 137.53 (C-9), 148.46
(C-8), 160.05 (C-3), 172.52 (C O). IR (neat): n= 3425, 2965, 2877,
¼
2840, 1725, 1614, 1556, 1519, 1468, 1364, 1308, 1249, 1205, 1170,
1122,1086,1035, 999, 916, 857, 812, 734, 700, 675 cmꢂ1. HRMS (ESI)
for C19H19O5 [M+ + H]: calculated 327.12327, found: 327.12319.
2.8. Synthesis of (11-oxo-2,3,5,6,7,11-hexahydro-1H-pyrano[2,3-f]
pyrido[3,2,1-ij]quinolin-9-yl) methyl butyrate, 12
To a solution of 9-(chloromethyl)-2,3,6,7-tetrahydro-1H-pyr-
(C-4a and C-4b), 173.42 (C
¼
O). IR (KBr 1%):
n
= 3067, 2965, 2934,
ano[2,3-f]pyrido[3,2,1-ij]quinolin-11(5H)-one
6
(0.042 mg,
2875, 1737, 1692, 1629, 1603, 1557, 1519, 1498, 1461, 1441, 1416,
1382, 1352, 1303, 1286, 1249, 1165, 1100, 1058, 1040, 1018, 976, 911,
862, 753, 733, 643 cmꢂ1. HRMS (ESI) for C18H18NO2 [M+ + H]:
calculated 280.13384, found: 280.13403.
1.45 ꢁ10ꢂ4 mol) in dry DMF (4 mL), potassium fluoride (0.025 g,
4.35 ꢁ10ꢂ4 mol) and butyric acid (0.014 mL, 1.59 ꢁ10ꢂ4 mol) were
added. The reaction was followed by TLC (ethyl acetate/light
petroleum, 1:4), and stirred at room temperature for 14 h. The
solvent was removed by rotary evaporation under reduced
pressure and the crude residue was purified by column chroma-
tography using mixtures of ethyl acetate/light petroleum as eluent.
Compound 12 was obtained as oil (0.017 g, 34%). Rf = 0.58 (ethyl
acetate/light petroleum, 1:4). 1H NMR (400 MHz, CDCl3): dH = 0.99
(t, J = 7.2 Hz, 3H, CH3—CH2—CH2), 1.73 (sext, J = 7.2 Hz, 2H,
CH3—CH2—CH2), 1.91–2.03 (m, 4H, H-2 and H-6), 2.42 (t,
J = 7.2 Hz, 2H, CH3—CH2—CH2), 2.76 (t, J = 6.4 Hz, 2H, H-7), 2.89 (t,
J = 6.4 Hz, 2H, H-1), 3.18–3.33 (m, 4H, H-3 and H-5), 5.20 (s, 2H,
CH2), 6.10 (s, 1H, H-10), 6.88 (s, 1H, H-8). 13C NMR (100.6 MHz,
CDCl3): dC = 13.66 (CH3—CH2—CH2), 18.37 (CH3—CH2—CH2), 20.39
(C-2), 20.55 (C-1), 21.45 (C-6), 27.67 (C-7), 36.00 (CH3—CH2—CH2),
49.48 (C-3), 49.88 (C-5), 61.17 (CH2), 105.49 (C-10), 105.80 (C-8a),
106.96 (C-12b), 118.20 (C-7a), 120.40 (C-8), 145.95 (C-7b), 149.68
2.6. Synthesis of (5-methoxy-3-oxo-3H-naphtho[2,1-b]pyran-1-yl)
methyl butyrate, 9
To a solution of 1-chloromethyl-5-methoxy-3-oxo-3H-naphtho
[2,1-b]pyran 3 (0.100 g, 3.64 ꢁ10ꢂ4 mol) in dry DMF (4 mL),
potassium fluoride (0.063 g, 1.09 ꢁ10ꢂ3 mol) and butyric acid
(0.033 mL, 3.64 ꢁ10ꢂ4 mol) were added. The reaction was followed
by TLC (ethyl acetate/light petroleum, 1:4), and stirred at room
temperature for 42 h. The solvent was removed by rotary
evaporation under reduced pressure and the crude residue was
purified by column chromatography using mixtures of ethyl
acetate/light petroleum as eluent. Compound 9 was obtained as an
oily solid (0.083 g, 70%). Rf = 0.22 (ethyl acetate/light petroleum,
1:4). 1H NMR (400 MHz, CDCl3): dH = 1.01 (t, J = 7.2 Hz, 3H, CH3—
CH2—CH2), 1.70–1.80 (m, 2H, CH3—CH2—CH2), 2.48 (t, J = 7.2 Hz, 2H,
CH3—CH2—CH2), 4.04 (s, 3H, OCH3), 5.64 (d, J = 1.2 Hz, 2H, CH 2),
6.70 (t, J = 1.2 Hz, 1H, H-2), 7.30 (s, 1H, H-6), 7.47–7.53 (m, 2H, H-
8 and H-9), 7.76–7.81 (m, 1H, H-10), 7.95–8.10 (m, 1H, H-7). 13C
NMR (100.6 MHz, CDCl3): dC = 13.62 (CH3—CH2—CH2), 18.32 (CH3—
CH2—CH2), 35.95 (CH3—CH2—CH2), 56.06 (OCH3), 63.94 (CH2),
110.81 (C-6),113.14 (C-2),113.43 (C-4b),123.94 (C-6b),124.40 (C-7),
125.89 (C-8), 125.98 (C-9), 128.42 (C-10), 131.09 (C-6a), 146.65 (C-
(C-9), 151.17 (C-12a), 162.26 (C-11), 172.93 (C
¼
O). IR (neat):
n
= 2958, 2933, 2873, 2856,1720,1605,1558,1522,1437,1382,1343,
1312, 1203, 1174, 1124, 1075, 1019, 884, 851, 753, 738, 701 cmꢂ1
.
HRMS (ESI) for C20H24NO4 [M+ + H]: calculated 342.17062, found:
342.17031.
2.9. Synthesis of (5-methoxy-3-thioxo-3H-naphtho[2,1-b]pyran-1-yl)
methyl butyrate, 13
4a), 146.81 (C-5), 151.46 (C-1), 159.43 (C-3), 172.65 (C
¼
O). IR (KBr
Lawesson’s reagent (0.268 g, 6.62 ꢁ10ꢂ4 mol) was added to a
solution of (5-methoxy-3-oxo-3H-naphtho[2,1-b]pyran-1-yl)
methyl butyrate 9 (0.072 g, 2.20 ꢁ10ꢂ4 mol) in toluene (8 mL).
The reaction mixture was refluxed for 9 h and the process was
followed by TLC (ethyl acetate/light petroleum, 1:4). The solvent
was removed by rotary evaporation under reduced pressure and
the crude residue was purified by column chromatography using
dichlorometane/light petroleum mixtures of increasing polarity as
eluent. Compound 13 was obtained as oil (0.004 g, 5%). Rf = 0.71
(ethyl acetate/light petroleum, 1:4). 1H NMR (400 MHz, CDCl3):
dH = 1.02 (t, J = 7.2 Hz, 3H, CH3—CH2—CH2), 1.70–1.81 (m, 2H, CH3—
CH2—CH2), 2.50 (t, J = 7.2 Hz, 2H, CH3—CH2—CH2), 4.10 (s, 3H,
OCH3), 5.66 (d, J = 1.2 Hz, 2H, CH2), 7.39 (s, 1H, H-6), 7.52–7.62 (m,
3H, H-2, H-8 and H-9), 7.81–7.86 (s, 1H, H-7), 8.03–8.10 (m, 1H, H-
10). 13C NMR (100.6 MHz, CDCl3): dC = 13.66 (CH3—CH2—CH2),18.39
(CH3—CH2—CH2), 35.99 (CH3—CH2—CH2), 56.24 (OCH3), 63.76
(CH2), 111.27 (C-6), 116.07 (C-4b), 123.76 (C-6b), 125.02 (C-10),
1%): = 3426, 3060, 2964, 2878, 2836, 1733, 1627, 1599, 1559, 1513,
n
1460, 1425, 1346, 1322, 1264, 1147, 1121, 1085, 1005, 932, 864, 835,
780, 738, 703 cmꢂ1. HRMS (ESI) for C19H19O5 [M+ + H]: calculated
327.12327, found: 327.12356.
2.7. Synthesis of (8-methoxy-3-oxo-3H-naphtho[2,1-b]pyran-1-yl)
methyl butyrate, 10
To a solution of 1-chloromethyl-8-methoxy-3-oxo-3H-naphtho
[2,1-b]pyran
4
(0.305 g 1.11 ꢁ10ꢂ3 mol) in dry DMF (5 mL),
potassium fluoride (0.193 g, 3.33 ꢁ10ꢂ3 mol) and butyric acid
(0.101 mL, 1.11 ꢁ10ꢂ3 mol) were added. The reaction was followed
by TLC (ethyl acetate/light petroleum, 1:4), and stirred at room
temperature for 44 h. The solvent was removed by rotary
evaporation under reduced pressure and the crude residue was
purified by column chromatography using mixtures of ethyl