Q.-Z. Zheng et al. / European Journal of Medicinal Chemistry 45 (2010) 3207e3212
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4.1.2.2. N-(4-fluorophenyl)morpholine-4-carboxamide (3b) [19].
White crystals, yield 68%, mp: 182e184 ꢁC. 1H NMR (300 MHz,
CDCl3)
d
: 3.48 (t, J ¼ 4.8 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.75(t,
J ¼ 5.0 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.33 (s, 1H, NH), 7.04 (t,
J ¼ 1.8 Hz, 1H, ArH), 7.34 (d, J ¼ 1.8 Hz, 2H, ArH); MS (ESI) 275
(M þ 1)þ. Anal. calcd for C11H12Cl2N2O2: C, 48.02; H, 4.40; N, 10.18.
Found: C, 48.00; H, 4.48; N, 10.11.
CDCl3)
d: 3.47 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.75
(t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.25 (s, 1H, NH),
6.96e7.02 (m, 2H, ArH), 7.28e7.32 (m, 2H, ArH); MS (ESI) 225
(M þ 1)þ. Anal. calcd for C11H13FN2O2: C, 58.92; H, 5.84; N, 12.49.
Found: C, 58.88; H, 5.85; N, 12.36.
4.1.2.12. (3,4-Dihydro-quinolin-1(2H)-yl)-4-morpholinylmethanone
(3l). Orange-yellow crystals, yield 71%, mp: 34e36 ꢁC. 1H NMR
4.1.2.3. N-(2-fluorophenyl)morpholine-4-carboxamide
(3c). Pink
(300 MHz, CDCl3) d: 1.97 (m, 2H, CH2, 3-tetrahydroquinoline), 2.75
powder, yield 58%, mp: 116e118 ꢁC. 1H NMR (300 MHz, CDCl3)
d:
(t, J ¼ 6.6 Hz, 2H, CH2, 3-tetrahydroquinoline), 3.30 (t, J ¼ 5.0 Hz, 4H,
2 ꢃ CH2, 3,5-morpholine), 3.59e3.63 (m, 6H, 3 ꢃ CH2, 2,6-mor-
pholine and 3-tetrahydroquinoline), 6.92e7.14 (m, 4H, 5,6,7,8-tet-
3.52 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.78 (t, J ¼ 5.1 Hz,
4H, 2 ꢃ CH2, 2,6-morpholine), 6.57 (s, 1H, NH), 6.96e7.13 (m, 3H,
ArH), 8.09 (t, J ¼ 8.0 Hz, 1H, ArH); MS (ESI) 225 (M þ 1)þ. Anal. calcd
for C11H13FN2O2: C, 58.92; H, 5.84; N, 12.49. Found: C, 58.91; H,
5.81; N, 12.53.
rahydroquinoline); MS (ESI) 247 (M
C14H18N2O2: C, 68.27; H, 7.37; N, 11.37. Found: C, 68.16; H, 7.36; N,
11.48.
þ
1)þ. Anal. calcd for
4.1.2.4. N-(2,4-difluorophenyl)morpholine-4-carboxamide (3d).
Orchid pink powder, yield 55%, mp: 152e154 ꢁC. 1H NMR (300 MHz,
4.1.2.13. N-(quinolin-8-yl) morpholine-4-carboxamide (3m). White
powder, yield 81%, mp: 103e105 ꢁC. 1H NMR (500 MHz, CDCl3)
d:
CDCl3)
d
: 3.48 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.74 (t,
3.68 (t, J ¼ 4.9 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.84 (t, J ¼ 4.9 Hz,
4H, 2 ꢃ CH2, 2,6-morpholine), 7.44e7.49 (m, 2H, 5,6-quinoline),
7.56 (t, J ¼ 8.0 Hz, 1H, 3-quinoline), 8.19 (d, J ¼ 8.6 Hz, 1H, 4-
quinoline), 8.58 (d, J ¼ 7.6 Hz,1H, 7-quinoline), 8.79e8.80 (m, 1H, 2-
quinoline), 9.45 (s, 1H, NH); MS (ESI) 258 (M þ 1)þ. Anal. calcd for
C14H15N3O2: C, 65.35; H, 5.88; N, 16.33. Found: C, 65.22; H, 5.92; N,
16.45.
J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.40 (s, 1H, NH), 6.81e6.88
(m, 2H, ArH), 7.96e8.04 (m, 1H, ArH); MS (ESI) 243 (M þ 1)þ. Anal.
calcd for C11H12F2N2O2: C, 54.54; H, 4.99; N, 11.57. Found: C, 54.52;
H, 5.05; N, 11.69.
4.1.2.5. N-(4-bromophenyl)morpholine-4-carboxamide (3e) [20].
White powder, yield 63%, mp: 200e201 ꢁC. 1H NMR (300 MHz,
CDCl3)
d
: 3.48 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.75 (t,
4.1.2.14. N-(9H-fluoren-2-yl) morpholine-4-carboxamide (3n).
Orange-yellow powder, yield 83%, mp: 228e230 ꢁC. 1H NMR
J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.28 (s, 1H, NH), 7.26 (d,
J ¼ 9.0 Hz, 2H, ArH), 7.40 (d, J ¼ 8.8 Hz, 2H, ArH); MS (ESI) 285
(M þ 1)þ. Anal. calcd for C11H13BrN2O2: C, 46.33; H,4.60; N, 9.82.
Found: C, 46.25; H, 4.51; N, 9.91.
(300 MHz, DMSO-d6)
d: 3.44 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-mor-
pholine), 3.62 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 3.86 (s,
2H, CH2, 9-fluorene), 7.21e7.78 (m, 7H, 1,3,4,5,6,7,8-fluorene), 8.61
(s, 1H, NH); MS (ESI) 295 (M þ 1)þ. Anal. calcd for C18H18N2O2: C,
73.45; H, 6.16; N, 9.52. Found: C, 73.54; H, 6.21; N, 9.61.
4.1.2.6. N-(2,4-dichlorophenyl)morpholine-4-carboxamide (3f).
Light yellow powder, yield 59%, mp: 141e143 ꢁC. 1H NMR
(300 MHz, CDCl3)
d
: 3.50 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-mor-
4.2. Antibacterial and antifungal assay
pholine), 3.75 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.93
(s, 1H, NH), 7.23 (dd, J ¼ 9.0, 2.4 Hz, 1H, ArH), 7.35 (d, J ¼ 2.4 Hz,
1H, ArH), 8.18 (d, J ¼ 8.8 Hz, 1H, ArH); MS (ESI) 275 (M þ 1)þ.
Anal. calcd for C11H12Cl2N2O2: C, 48.02; H, 4.40; N, 10.18.
Found: C, 48.15; H, 4.31; N, 10.06.
The antibacterial and antifungal activities of the synthesized
compounds were tested against E. coli ATCC 35218, P. aeruginosa
ATCC 13525, B. subtilis ATCC 6633 and S. aureus ATCC 6538 using
MH medium (MuellereHinton medium: casein hydrolysate 17.5 g,
soluble starch 1.5 g, beef extract 1000 mL), and the antifungal
activity of the compounds was tested against A. niger ATCC 16404, T.
rubrum ATCC 10218 using RPMI-1640 medium (RPMI-1640 (GIBCO
BRL) 10 g, NaHCO3 2.0 g, 0.165 mol/L morpholinepropanesulfonic
acid (MOPS) (Sigma) (34.5 g), triple distilled water 900 ml, buffered
to pH 7.0 with 1 mol/L NaOH (25 ꢁC), metered volume to 1000 ml,
filtered sterilization, conservation at 4 ꢁC). The MICs (minimum
inhibitory concentrations) of the test compounds were determined
by a colorimetric method using the dye MTT (3-(4,5-dimethylth-
iazol-2-yl)-2,5-diphenyl tetrazolium bromide) [25]. A stock solu-
4.1.2.7. N-(2-chlorophenyl)morpholine-4-carboxamide(3g) [21]. Light
yellow powder, yield 61%, mp: 125e126 ꢁC. 1H NMR (300 MHz,
CDCl3)
d
: 3.53 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine), 3.78 (t,
J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.94 (s, 1H, NH), 6.98 (d,
J ¼ 7.5 Hz, 1H, ArH), 7.23e7.35 (m, 2H, ArH), 8.20 (d, J ¼ 8.2 Hz, 1H,
ArH); MS (ESI) 241 (M þ 1)þ. Anal. calcd for C11H13ClN2O2: C, 54.89;
H, 5.44; N, 11.64. Found: C, 54.78; H, 5.45; N, 11.73.
4.1.2.8. N-phenylmorp holine-4-carboxamide (3h). Light yellow
powder, yield 64%, mp: 160e161 ꢁC [Ref. [22] 159e160 ꢁC].
tion of the synthesized compound (50
mg/mL) in DMSO was
prepared and graded quantities of the test compounds were
incorporated in specified quantity of sterilized liquid medium (MH
medium for antibacterial activity and RPMI-1640 medium for
antifungal activity). A specified quantity of the medium containing
the compound was poured into microtitration plates. Suspension of
the microorganism was prepared to contain approximately 105 cfu/
mL and applied to microtitration plates with serially diluted
compounds in DMSO to be tested and incubated at 37 ꢁC for 24 h.
After the MICs were visually determined on each of the micro-
4.1.2.9. N-p-tolylmorpholine-4-carboxamide
(3i)
[23]. White
powder, yield 66%, mp: 155e156 ꢁC. 1H NMR (300 MHz, CDCl3)
d:
2.30 (s, 3H, CH3), 3.47 (t, J ¼ 4.6 Hz, 4H, 2 ꢃ CH2, 3,5-morpholine),
3.74 (t, J ¼ 5.1 Hz, 4H, 2 ꢃ CH2, 2,6-morpholine), 6.24 (s, 1H, NH),
7.10 (d, J ¼ 9.0 Hz, 2H, ArH), 7.22 (d, J ¼ 8.4 Hz, 2H, ArH); MS (ESI)
221 (M þ 1)þ. Anal. calcd for C12H16N2O2: C, 65.43; H,7.32; N, 12.72.
Found: C, 65.51; H, 7.28; N, 12.65.
4.1.2.10. N-(4-methoxyphenyl)morpholine-4-carboxamide
(3j).
titration plates, 50 mL of PBS (Phosphate Buffered Saline 0.01 mol/L,
Yellow powder, yield 73%, mp: 122e123 ꢁC [Ref. [24] 126e127 ꢁC].
pH 7.4, Na2HPO4$12H2O 2.9 g, KH2PO4 0.2 g, NaCl 8.0 g, KCl 0.2 g,
distilled water 1000 mL) containing 2 mg of MTT/mL was added to
each well. Incubation was continued at room temperature for
4.1.2.11. N-(3,5-dichlorophenyl)morpholine-4-carboxamide
(3k).
Milk-white powder, yield 62%, mp: 166e168 ꢁC. 1H NMR (300 MHz,
4e5 h. The content of each well was removed, and 100
mL of