THE SYNTHESIS OF (1,3,4-Oxadiazol-2-yl)ACRYLIC ACID DERIVATIVES
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EXPERIMENTAL
3.60; N 11.60. С12Н10N2О4. Calc., %: С 58.55; Н 4.06;
N 11.37.
1H NMR spectra (δ, ppm, J, Hz) were recorded on
a Bruker DPX-250 spectrometer (working frequency
250 MHz) in DMSO-d6 using tetramethylsilane as a
standard. Melting points were measured in an open
capillary on a Chimlabpribor PTP device. Element
analysis was carried out on an Elementar Vario Micro
cube CHNS-analyzer. The reaction course and the
product purity were monitored by TLC on Silufol
UV-254 plates.
(Z)-3-[5-(2-Methoxyphenyl)-1,3,4-oxadiazol-2-yl]-
acrylic acid (IVe). Colorless crystals. The yield 55%.
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mp 195–196°C. Н NMR: 3.98 (s, 3Н, ОСН3), 6.93
(d, 1Н, arom., J 8.4), 7.13 (dd, 1Н, arom., J 8.4, 8.4),
7.25 (d, 1Н, СН=СН, J 5.7), 7.58 (dd, 1Н, arom.,
J 8.4, 8.4), 7.89 (d, 1Н, СН=СН, J 5.7), 7.95 (d, 1Н,
arom., J 8.4), 11.44 (s, 1Н, СООН). Found, %: С
58.90; Н 3.60; N 11.60. С12Н10N2О4. Calc., %: С
58.55; Н 4.06; N 11.37.
(Z)-3-[5-(2-Furyl)-1,3,4-oxadiazol-2-yl]acrylic
acid (IVа). A solution of maleic anhydride (0.02 mol)
in СН3СООН (4 mL) was added to a solution of 2-
furoic acid hydrazide (0.02 mol) in СН3СООН
(5 mL). Immediately, the mixture was warmed and a
white precipitate was formed. The mixture was stirred
for 1.5 h at room temperature. The precipitate was sep-
arated and washed twice with acetic acid and ethanol.
Without additional purification, the resulting acylhy-
(Z)-3-[5-(4-Chlorophenyl)-1,3,4-oxadiazol-2-yl]-
acrylic acid (IVf). Colorless crystals. The yield 48%.
1
mp 179°C. Н NMR: 6.93 (d, 1Н, СН=СН, J 5.7),
7.56 (d, 2Н, arom., J 8.4), 7.88 (d, 2Н, arom., J 8.4),
7.94 (d, 1Н, СН=СН, J 5.7), 11.83 (s, 1Н, СООН).
Found, %: С 52.40; Н 3.20; Cl 13.80; N 11.50. С11Н7-
ClN2О3. Calc., %: С 52.72; Н 2.79; Cl 14.17; N 11.17.
(Z)-3-[5-(4-Bromophenyl)-1,3,4-oxadiazol-2-yl]-
drazide was subjected to the reaction with a solution of acrylic acid (IVg). Colorless crystals. The yield 66%.
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POCl3 (0.02 mol) in DMF (7 mL). The solution was
stirred for 2 h at room temperature and poured into
Н2О (50 mL). The precipitate was separated, washed
twice with water and recrystallized from ethanol to
give colorless crystals (72%); mp 205–206°C.
1Н NMR: 6.78 (s, 1Н, fur.), 6.84 (d, 1Н, СН=СН, J
5.5), 7.42 (s, 1 Н, fur.), 7.48 (d, 1Н, СН=СН, J 5.5),
8.11 (s, 1Н, fur.), 13.24 (s, 1Н, СООН). Found, %: С
52.10; Н 3.00; N 13.40. С9Н6N2О4. Calc., %: С 52.43;
Н 2.93; N 13.59.
mp 252°C. Н NMR: 6.93 (d, 1 Н, СН=СН, J 5.7),
7.70 (d, 2Н, arom., J 8.4), 7.80 (d, 2Н, arom., J 8.4),
7.94 (d, 1Н, СН=СН, J 5.7), 11.83 (s, 1Н, СООН).
Found, %: С 45.20; Н 2.50; Br 26.50; N 10.00.
С11Н7BrN2О3. Calc., %: С 44.78; Н 2.37; Br 27.08; N
9.49.
(Е)-3-[5-(4-Nitrophenyl)-1,3,4-oxadiazol-2-yl]-
acrylic acid (IVh). Colorless crystals. The yield 79%.
1
mp 223–224°C. Н NMR: 6.73 (d, 1Н, СН=СН, J
12.6), 6.96 (d, 1Н, СН=СН, J 12.6), 8.21 (d, 2Н,
arom., J 9.0), 8.45 (d, 2Н, arom., J 9.0), 13.45 (s, 1Н,
СООН). Found, %: С 50.80; Н 2.20; N 16.50.
С11Н7N3О5. Calc., %: С 50.59; Н 2.68; N 16.09.
Compounds (IVb)–(IVm) were prepared similarly
to compound (IVа).
(Z)-3-[5-(2,7а-Dihydro-1,3-benzothiazol-2-ylsul-
fanylmethyl)-1,3,4-oxadiazol-2-yl]acrylic acid (IVb).
Colorless crystals. The yield 68%. mp 197–198°C.
1Н NMR: 4.38 (s, 2Н, СН2), 6.92 (d, 1Н, СН=СН,
J 5.7), 7.35 (dd, 1Н, arom., J 8.1, 8.1), 7.48 (dd, 1Н,
arom., J 8.1, 8.1), 7.84 (d, 1Н, arom., J 8.1), 7.90 (d,
1Н, СН=СН, J 5.7), 8.02 (d, 1Н, arom., J 8.1), 11.88
(s, 1Н, СООН). Found, %: С 48.90; Н 2.50; N 12.40;
S 14.60. С13Н9N3О3S2. Calc., %: С 48.89; Н 2.84; N
13.16; S 20.08.
(Е)-3-[5-(2Н-Thiophen-2-yl)-1,3,4-oxadiazol-2-
yl]acrylic acid (IVi). Colorless crystals. The yield 80%.
1
mp 234–235°C. Н NMR: 6.85 (d, 1Н, СН=СН, J
15.9), 7.32 (dd, 1Н, thioph., J 4.8, 3.6), 7.43 (d, 1Н,
СН=СН, J 15.9), 7.96 (dd, 1Н, thioph., J 3.6, 1.2),
8.01 (dd, 1Н, thioph., J 4.8, 1.2), 13.24 (s, 1Н,
СООН). Found, %: С 48.90; Н 2.50; N 12.40; S
14.60. С9Н6N2О3S. Calc., %: С 48.66; Н 2.70; N
12.60; S 14.43.
(Z)-3-[5-(3-Hydroxy-2-naphtyl)-1,3,4-oxadiazol-
2-yl]acrylic acid (IVj). Colorless crystals. The yield
71%. mp 192–195°C. 1Н NMR: 6.95 (d, 1Н,
СН=СН, J 5.7), 7.33 (s, 1Н, arom.), 7.36 (dd, 1Н,
arom., J 7.5, 7.5), 7.52 (dd, 1Н, arom., J 7.5, 7.5), 7.76
(d, 1Н, arom., J 8.1), 7.99 (2Н, arom. + СН=СН,
J 5.7), 8.66 (s, 1Н, arom.), 11.97 (s, 1Н, ОН), 12.05 (s,
1Н, СООН). Found, %: С 63.40; Н 3.90; N 10.30.
С15Н10N2О4. Calc., %: С 63.85; Н 3.54; N 9.92.
(Е)-3-[5-(p-Tolyl)-1,3,4-oxadiazol-2-yl]acrylic acid
(IVc). Colorless crystals. The yield 84%. mp 212–
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213°C. Н NMR: 2.40 (s, 3Н, СН3), 6.92 (d, 1Н,
СН=СН, J 15.9), 7.42 (d, 2Н, arom., J 8.1), 7.43 (d,
1Н, СН=СН, J 15.9), 8.01 (d, 2Н, arom., J 8.1), 13.25
(s, 1Н, СООН). Found, %: С 62.90; Н 3.90; N 11.80.
С12Н10N2О3. Calc., %: С 62.63; Н 4.35; N 12.17.
(Е)-3-[5-(4-Methoxyphenyl)-1,3,4-oxadiazol-2-
yl]acrylic acid (IVd). Colorless crystals. The yield 90%.
(Z)-3-[5-(2,6-Dihydroxyphenyl)-1,3,4-oxadiazol-
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mp 227–228°C. Н NMR: 3.85 (s, 3Н, ОСН3), 6.90 2-yl]acrylic acid (IVk). Colorless crystals. The yield
(d, 1Н, СН=СН, J 16.2), 7.15 (d, 2Н, arom., J 9.0), 59%. mp 250–255°C. 1Н NMR: 6.43 (d, 2Н, arom., J
7.43 (d, 1Н, СН=СН, J 16.2), 8.05 (d, 2Н, arom., J 8.4), 6.98 (d, 1Н, СН=СН, J 5.7), 7.27 (dd, 1Н,
9.0), 13.20 (s, 1Н, СООН). Found, %: С 58.90; Н arom., J 8.4, 8.4), 7.99 (d, 1Н, СН=СН, J 5.7), 12.16
RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY Vol. 44 No. 2 2018