January 2009
Reactivity of 3-Cyano-N-ethoxycarbonyl-iminocoumarin with
Hydrazides as N-Nucleophiles
31
Table 2
Maximum absorption wavelength (kabs), maximum excitation wavelength (kex), maximum emission wavelength (kem), and fluorescence lifetime (s)
for compounds 12, 13, and 15 in dimethylsulfoxide and dichloromethane.
Compound
kabs (nm)
kex (nm)
kem (nm)
s (ns)
12 (DMSO)
13 (DMSO)
13 (CH2Cl2)
15 (DMSO)
15 (CH2Cl2)
504
486
484 (508 sh)
508
502
458
476
480
480
451
520
518
502
520
507
2.6 ꢂ 0.3
2.9 ꢂ 0.2
3.2 ꢂ 0.2
1.5 ꢂ 0.2
1.9 ꢂ 0.2
UV/vis absorption spectra were recorded on a Hewlett-Pack-
ard 8452A diode array spectrophotometer. Steady state fluores-
cence work was performed on a Photon Technology Interna-
tional (PTI) Quanta Master 1 spectrofluorometer. All excitation
and emission spectra were corrected. Fluorescence decay was
measured with the stroboscopic technique using a Strobe Mas-
ter fluorescence lifetime spectrophotometer from PTI. The ex-
citation source was a flash lamp filled with a mixture of nitro-
gen and helium (30/70). Data were collected over 200 chan-
nels with a time-base of 0.1 ns per channel. Analysis of fluo-
rescence decay was performed using the multiexponential
method software from PTI. All spectrophotometric measure-
ments were conducted in a thermostated cell at 25ꢁC.
4-[2-(2-Thienylcarbonyl)hydrazino]-8-diethylamino-2-oxo-
2H-benzopyrano[2,3-d]pyrimidine (13). Mp: 247ꢁC. IR
(cmꢀ1): 1619 (C¼¼N), 1639 (C¼¼O), 1660 (NACOAN), 3289
1
(NH). H NMR: d ¼ 1.14 (t, J ¼ 7.0 Hz, 6H, CH3), 3.51 (q, J
¼ 7.0 Hz, 4H, CH2N), 6.76 (d, J ¼ 2.1 Hz, 1H, H9), 6.61 (s,
1H, COR), 6.89 (dd, J ¼ 9.0, 2.1 Hz, 1H, H7), 7.18 (s, 1H,
COR), 7.71 (d, J ¼ 9.0 Hz, 1H, H6), 7.80 (s, 1H, COR) , 8.46
(s, 1H, H5), 10.46 (s,1H, NH), 10.69 (s, 1H, NH). Anal. Calcd.
for C20H19N5O3S: C, 58.67; H, 4.68; N, 17.10. Found: C,
59.01; H, 4.64; N, 17.11.
4-[2-(4-Hydroxybenzoyl)hydrazino]-8-diethylamino-2-oxo-
2H-benzopyrano[2,3-d]pyrimidine (14). Mp: 270ꢁC. IR
(cmꢀ1): 1608 (C¼¼N), 1636 (C¼¼O), 1664 (NACOAN), 3326
(NH), 3423 (OH). 1H NMR: d ¼ 1.13 (t, J ¼ 6.9 Hz, 6H,
CH3), 3.50 (q, J ¼ 6.9 Hz, 4H, CH2N), 6.73 (s, 1H, H9), 6.82
(d, J ¼ 8.7 Hz, 2H, COR), 7.77 (d, J ¼ 8.7 Hz, 2H, COR),
6.85 (d, J ¼ 9.3 Hz, 1H, H7), 7.72 (d, J ¼ 9.3 Hz, 1H, H6),
8.42 (s, 1H, H5), 10.28 (s,1H, OH), 10.46 (s,1H, NH), 10.69
(s, 1H, NH). Anal. Calcd. for C22H21N5O4: C, 63.00; H, 5.05;
N, 16.70. Found: C, 62.90; H, 5.23; N, 17.71.
4-[2-(4-Aminobenzoyl)hydrazino]-8-diethylamino-2-oxo-2H-
benzopyrano[2,3-d]pyrimidine (15). Mp: 245ꢁC. IR (cmꢀ1):
1605 (C¼¼N), 1637 (C¼¼O), 1663 (NACOAN), 3210 and 3334
(NH), 3439 (NH2). 1H NMR: d ¼ 1.12 (t, J ¼ 6.9 Hz, 6H,
CH3), 3.47 (q, J ¼ 6.9 Hz, 4H, CH2N), 5.71 (s, 2H, NH2),
6.57 (d, J ¼ 8.4 Hz, 2H, COR), 6.65 (d, J ¼ 8.4 Hz, 2H,
COR), 6.69 (s, 1H, H9), 6.82 (d, J ¼ 9.3 Hz, 1H, H7), 7.67 (d,
J ¼ 9.3 Hz, 1H, H6), 8.36 (s, 1H, H5), 10.16 (s,1H, NH),
10.60 (s, 1H, NH). 13C NMR: d ¼ 12.69 (CH3), 44.84
(CH2ANH), 96.68 (C9), 105.67, 109.90 (C12, C13), 111.58
(C7), 112.77 (CHAR), 120.49 (CAR) 129.78 (C6), 131.67
(CHAR),136.96 (C5), 137.38 (CAR), 152.32 (C8), 152.93
(C4), 155.81 (C10), 156.30 (C11) 163.57 (C¼¼O), 168.09
(NHAC¼¼O). Anal. Calcd. for C22H22N6O3: C, 63.15; H, 5.30;
N, 20.08. Found: C, 62.90; H, 5.33; N, 20.00.
4-[2-(2-Furoyl)hydrazino]-8-diethylamino-2-oxo-2H-benzo-
pyrano[2,3-d]pyrimidine (16). Mp: 246ꢁC. IR (cmꢀ1): 1607
(C¼¼N), 1636 (C¼¼O), 1663 (NACOAN), 3290 (NH). 1H
NMR: d ¼ 1.13 (t, J ¼ 7.0 Hz, 6H, CH3), 3.51 (q, J ¼ 7.0
Hz, 4H, CH2N), 6.66 (m, 1H, COR), 6.76 (d, J ¼ 2.1 Hz, 1H,
H9), 6.89 (dd, J ¼ 9.0, 2.1 Hz, 1H, H7), 7.24 (d, 1H, COR),
7.76 (d, J ¼ 9.0 Hz, 1H, H6), 7.89 (m, 1H, COR), 8.46 (s, 1H,
H5), 10.15 (s,1H, NH), 10.55 (s, 1H, NH). Anal. Calcd. for
C20H19N5O4: C, 61.06; H, 4.87; N, 17.80. Found: C, 61.20; H,
4.93; N, 17.84.
3-Cyano-N-ethoxycarbonyl-7-diethylamino iminocoumarin
1. 3-Cyano-N-ethoxycarbonyl-7-diethylamino iminocoumarin 1
was prepared as previously described in [9].
General procedure for the synthesis of benzopyranopyri-
midines 11–19. A solution of 3-cyano-N-ethoxycarbonyl-7-
diethylamino iminocoumarin 1 (1.56 g, 5 mmol) and (5 mmol)
of hydrazide in 30 mL of absolute methanol was refluxed dur-
ing the time indicated in Table 1. After complete reaction, the
benzopyranopyrimidine obtained was separated by filtration
and washed with ethanol. For spectroscopic use, compound 12,
13, and 15 were purified on TLC plates using chloroform as
the eluent.
4-(2-Benzoylhydrazino)-8-diethylamino-2-oxo-2H-benzopyr-
ano[2,3-d]pyrimidine (11). Mp: 244ꢁC. IR (cmꢀ1): 1632
(C¼¼N), 1644 (C¼¼O), 1664 (NACOAN), 3331 (NH). 1H
NMR: d ¼ 1.14 (t, J ¼ 6.9 Hz, 6H, CH3), 3.51 (q, J ¼ 6.9
Hz, 4H, CH2N), 6.74 (s, 1H, H9), 6.88 (d, J ¼ 9.0, 1H, H7),
7.45–7.55 (3 H, COR), 7.75 (d, J ¼ 9.0 Hz, 1H, H6), 7.87–
7.89 (2 H, COR), 8.47 (s, 1H, H5), 10.49 (s, 1H, NH), 10.64
(s, 1H, NH). Anal. Calcd. for C22H21N5O3: C, 65.50; H, 5.25;
N, 17.36. Found: C, 65.46; H, 5.33; N, 17.35.
4-[2-(3-Fluorobenzoyl)hydrazino]-8-diethylamino-2-oxo-
2H-benzopyrano[2,3-d]pyrimidine (12). Mp: 249ꢁC. IR
(cmꢀ1): 1634 (C¼¼N, C¼¼O), 1664 (NACOAN), 3331 and
1
3335 (NH). H NMR: d ¼ 1.14 (t, J ¼ 6.9 Hz, 6H, CH3), 3.51
(q, J ¼ 6.9 Hz, 4H, CH2N), 6.75 (s, 1H, H9), 6.89 (dd, J ¼
7.2, 1.8 Hz, 1H, H7), 7.39 (m, 1H, COR), 7.53 (m, 1H, COR),
7.76 (m, 2H, COR), 7.74 (d, J ¼ 7.2, 1H, H6), 8.49 (s, 1H,
H5), 10.50 (s,1H, NH), 10.60 (s, 1H, NH). 13C NMR: d ¼
12.71 (CH3), 44.90 (CH2ANH), 96.73 (C9), 104.92, 110.00
(C12, C13), 111.80 (C7), 114.74, 118.26, 124.35, 130.63
(CHAR), 132.02 (C6), 136.76 (R), 138.04 (C5), 140.76 (C8),
153.31 (C4), 156.14 (C10), 160.52 (C11), 162.13 (CAF), 163.75
(C¼¼O), 167.95 (NHAC¼¼O). Anal. Calcd. for C22H20FN5O3:
C, 62.70; H, 4.78; N, 16.62. Found: C, 63.10; H, 4.80; N,
16.50.
4-(2-Isonicotinoylhydrazino)-8-diethylamino-2-oxo-2H-ben-
zopyrano[2,3-d]pyrimidine (17). Mp: >270ꢁC. IR (cmꢀ1):
1
1607 (C¼¼N), 1640 (C¼¼O), 1661 (NACOAN),3234 (NH). H
NMR: d ¼ 1.15 (t, J ¼ 6.9 Hz, 6H, CH3), 3.52 (q, J ¼ 6.9
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet