JOURNAL OF THE CHINESE
CHEMICAL SOCIETY
Efficient synthesis of 5(4H)-oxazolones and their antimicrobial evaluation
+
13
MS (m/z): 279 (M ); Anal. Cald. for C H NO : C,
J = 8.4 Hz, Ar-H), 7.51 (d, 2H, J = 8.4 Hz, Ar-H);
C
1
7
13
3
7
4
3.11; H, 4.65; N, 5.01%. Found: C, 73.07; H,
.66; N, 5.05%.
NMR (100 MHz, CDCl , δ, ppm): 23.7, 51.9, 112.3,
3
128.0, 129.5, 131.2, 132.5, 135.8, 143.2, 166.7, 174.1;
+
2
-Phenyl-4-(4-chloro
arylidene)-1,3-oxazol-5-one
ESI-MS (m/z): 293 (M ); Anal. Cald. for
ꢀ
(5c). Light yellow crystals; m.p.: 173 C; IR (KBr, νmax,
C H NO : C, 73.71; H, 5.15; N, 4.78%; Found C,
18
15
3
−1
1
cm ): 1450, 1654, 1766; H NMR (90 MHz, CDCl ,
73.70; H, 5.13; N, 4.76%.
3
νmax, δ, ppm): 7.3 (s, Ar-H, 1H), 7.1–7.7 (m, 6H, Ar-
H), 8.0–8.2 (m, 3H, Ar-H); C NMR (22.5 MHz,
2-(4-Methoxy phenyl)-4-(4-methoxy arylidene)-1,3-
1
3
ꢀ
oxazol-5-one (5h). Yellow crystals; m.p.: 146 C; IR
−
CDCl , δ, ppm): 131.6, 134.8, 165.3, 166.7; GC-MS (m/
(KBr, ν , cm 1): 934, 1134, 1476, 1657, 1765, 1834;
3
max
+
1
z): 283 (M ); Anal. Cald. for C H NO Cl: C,
H NMR ( 400 MHz, CDCl , δ, ppm): 3.54 (s, 3H,
1
6
10
2
3
6
3
7.72; H, 3.52; N, 4.93%. Found: C, 67.69; H,
.55; N, 4.88%.
OCH ), 3.81 (s, 3H, OCH ), 7.09 (s, 1H, CH), 7.18 (d,
2H, J = 8.4 Hz, Ar-H), 7.21 (d, 2H, J = 8.4 Hz, Ar-H),
3
3
2
-Phenyl-4-(3-methoxy, 4-hydroxy arylidene)-1,3-
7.32 (d, 2H, J = 8.8 Hz, Ar-H), 7.39 (d, 2H, J = 8.8
ꢀ
13
oxazol-5-one (5d). Yellow crystals; m.p.: 210 C; IR
KBr, νmax, cm ): 1452, 1650, 1755; H NMR
90 MHz, CDCl , δ, ppm): 3.9 (s, 3H, OCH ), 7.1 (s,
Hz, Ar-H); C NMR (100 MHz, CDCl , δ, ppm):
3
−1
1
(
(
53.0, 55.5, 110.5, 126.4, 128.0, 131.1, 132.1, 134.6,
+
142.2, 158.1, 166.8, 173.8; ESI-MS (m/z): 309 (M );
3
3
1
H, Ar-CH), 7.1–7.2 (m, 3H, Ar-H), 7.4–7.6 (m, 5H,
Anal. Cald. for C H NO : C, 69.89; H, 4.89; N,
4.53%; Found C, 69.88; H, 4.82; N, 4.55%.
18
15
4
1
3
Ar-H), 8.4 (s, 1H, OH); C NMR (22.5 MHz, CDCl3,
δ, ppm): 55.0, 127.6, 131.9, 161.9, 168.2; GC-MS (m/z):
2-(4-Methoxy phenyl)-4-(4-bromo arylidene)-1,3-
+
ꢀ
2
3
95 (M ); Anal. Cald. for C H NO : C, 67.72; H,
.52; N, 4.93%. Found: C, 67.46; H, 3.53; N, 4.64%.
oxazol-5-one (5i). Yellow crystals; m.p.: 169 C; IR
1
7
13
4
−
1
1
(KBr, νmax, cm ): 781, 962, 1166, 1424, 1662, 1788; H
NMR (400 MHz, CDCl , δ, ppm): 3.79 (s, 3H, OCH ),
2
-Phenyl-4-(3-nitro
arylidene)-1,3-oxazol-5-one
3
3
ꢀ
(
5e). Yellow crystals; m.p.: 192 C; IR (KBr, νmax
cm ): 1530, 1657, 1768; H NMR (90 MHz, CDCl , δ,
,
7.19 ( s, 1H, CH), 7.28 (d, 2H, J = 8.8 Hz, Ar-H), 7.32
(d, 2H, J = 9.2 Hz, Ar-H), 7.42 (d, 2H, J = 8.8 Hz, Ar-
−1
1
3
13
ppm): 7.2 (s, 1H, Ar-CH), 7.5–7.7 (m, 4H, Ar-H),
H), 7.46 (d, 2H, J = 8.8 Hz, Ar-H);
C NMR
8
9
1
.1–8.3 (m, 3H, Ar-H), 8.4 (d, J = 8.2 Hz, 1H, Ar-H),
(100 MHz, CDCl , δ, ppm): 53.1, 114.5, 128.0, 128.9,
3
13
.2 (s, 1H); C NMR (22.5 MHz, CDCl , δ, ppm):
130.2, 131.2, 131.7, 133.4, 135.8, 137.3, 143.2, 166.2,
3
+
+
31.0, 139.4, 164.4, 167.6; GC-MS (m/z): 294 (M );
174.5; ESI-MS (m/z): 358 (M ), 360 (M + 2); Anal.
Anal. Cald. for C H N O : C, 65.30; H, 3.40; N,
Cald. for C H BrNO : C, 57.00; H, 3.38; N, 3.91%;
1
6
10
2
4
17 12
3
9
9
.52; O, 21.76%. Found: C, 65.27; H, 3.42; N,
.50; O, 21.75%.
Found C, 57.10; H, 3.45; N, 3.68%.
2-(4-Methoxy phenyl)-4-(4-nitro arylidene)-1,3-oxa-
ꢀ
2
-(4-Hydroxy phenyl)-4-(4-chloro arylidene)-1,3-
zol-5-one (5j). Bright yellow crystals; m.p.: 188 C; IR
ꢀ
−1
1
oxazol-5-one (5f ). Yellow crystals; m.p.: 196 C; IR
(KBr, νmax, cm ): 959, 1154, 1498, 1671; H NMR
(400MHz, CDCl , δ, ppm): 3.91 (s, 3H, OCH ), 7.13 (s,
−
1
(KBr, ν , cm ): 692, 810, 1064, 1562, 1768, 2364,
max
3
3
1
−1
3
462; H NMR (90 MHz, ν , cm ): 7.1 (s, 1H, Ar-
1H, CH), 7.27 (d, 2H, J = 8.4 Hz, Ar-H), 7.34 (d, 2H,
J = 8.8 Hz, Ar-H), 7.59–7.65 (m, 4H, Ar-H);
max
13
CH), 7.4–7.5 ( m, 4H, Ar-H), 8.1–8.2 (m, 4H, Ar-H),
8
C
1
3
.4 (s, 1H, OH); C NMR (22.5 MHz, CDCl , δ,
NMR (100 MHz, CDCl , δ, ppm): 53.4, 115.3, 123.6,
3
3
ppm): 131.6, 134.8, 164.9, 166.7; GC-MS (m/z):
128.1, 131.4, 132.6, 134.5, 135.8, 139.1, 148.1, 165.5,
175.3; ESI-MS (m/z): 324 (M ); Anal. Cald. for
+
+
299
(M )
301
(M + 2);
Anal.
Cald.
for
C H NO Cl: C, 64.21; H, 3.34; N, 4.68; O, 16.05%.
C H N O : C, 62.96; H, 3.73; N, 8.64%. Found C,
1
6
10
3
17 12
2
5
Found: C, 64.19; H, 3.34; N, 4.65; O, 16.00%.
62.98; H, 3.71; N, 8.60%.
2
-(4-Methoxy Phenyl)-4-(4-methyl arylidene)-1,3-
ꢀ
oxazol-5-one (5g). Pale yellow crystals; m.p.: 145 C; IR
KBr, νmax, cm ): 956, 1128, 1455, 1623; H NMR
400 MHz, CDCl , δ, ppm): 2.89 (s, 3H, CH ), 3.85 (s,
Microbial cultures
−1
1
(
(
Bacterial strains E. coli, S. faecalis, P. vulgaris,
K. pneumonia, and E. faecalis and fungi P. expansum,
C. herbarum, and A. flavus were obtained from the
Department of Microbiology, Andhra University.
3
3
3
H, OCH ), 7.20 (s, 1H, CH), 7.24 (d, 2H, J = 8.8 Hz,
3
Ar-H), 7.35 (d, 2H, J = 8.8 Hz, Ar-H), 7.44 (d, 2H,
J. Chin. Chem. Soc. 2016
© 2016 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.jccs.wiley-vch.de
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