Synthesis, Anti-Inflammatory, and Analgesic Activities of Derivatives of 4-Hydroxy-2-benzoxazolone

Zheng, Guangjin; Chen, Tieyu; Peng, Xing; Long, Shengjing

doi:https://doi.org/10.1155/2015/534156

Journal of Chemistry

On this page

Abstract Introduction Experimental Discussion Supplementary Materials References Copyright Related Articles

Research Article | Open Access

Volume 2015 | Article ID 534156 | https://doi.org/10.1155/2015/534156

Synthesis, Anti-Inflammatory, and Analgesic Activities of Derivatives of 4-Hydroxy-2-benzoxazolone

Guangjin Zheng,¹Tieyu Chen,¹Xing Peng,¹and Shengjing Long¹

Academic Editor: Patricia Valentao

Received06 Mar 2015

Revised14 Jun 2015

Accepted16 Jun 2015

Published08 Jul 2015

Abstract

Benzoxazolones are widely distributed in plants and are of increasing interest for a variety of pharmacological properties, such as detoxification, antibacterial, anti-inflammatory, and analgesic activities and tranquilizers (Michaelidou and Hadjipavlou-Litina, 2005; Doğruer et al., 1998). 4-Hydroxy-2-benzoxazolone (HBOA) is one of the major bioactive compounds in traditional Chinese herb drug Acanthus ilicifolius (Peng and Long, 2006) which has obvious anti-inflammatory and analgesic activities (Huo et al., 2004; Mani Senthil Kumar et al., 2008; Babu et al., 2001). In this research, we used 2-nitroresorcinol as starting material to prepare HBOA with a novel “one-pot-way.” Derivatives of HBOA TC-2∼TC-4 were obtained via electrophilic reagents and reacted with corresponding primary amines to afford Schiff Base derivatives TC-5∼TC-10 for further study. Anti-inflammatory and analgesic activities of those derivatives were determined by using carrageenan-induced rat paw edema test. The analgesic activities of the derivatives were determined by the hot-plate test.

1. Introduction

In recent years, reports showed Acanthus ilicifolius has obvious anti-inflammatory, analgesic activities, and 4-hydroxy-2-benzoxazolone (HBOA) is one of the major bioactive benzoxazolones compounds [1]. According to modern medicinal theory, HBOA is a bioisosterism of Chlorzoxazone and has the possibility to be a kind of nonsteroidal anti-inflammatory drugs (NSAIDs). Since benzoxazolones are of bioactivities, many molecular modification and preliminary bioactivity evaluation studies have been performed [1–3]. Several useful compounds have been developed and evaluated for their analgesic properties, anti-inflammatory properties, and antifungal properties [4–7]. Nevertheless, most efforts focused on N-, 4-, 5-, or 6-substituted HBOA. Currently, 7-substituted benzoxazolone derivatives as well as their anti-inflammatory or analgesic properties have been scarcely reported. Therefore, we report the new method for synthesis of HBOA (Scheme 1), some new C-7 HBOA derivatives and their anti-inflammatory as well as analgesic activities.

2. Experimental

Reagents and solvents used below were obtained from commercial sources. Melting points were measured by X4 micromelting point appearance. IR spectra were obtained with Perkin-Elmer Spectrum 100. The ¹H-NMR and ¹³C-NMR spectra were run on a Bruker AVTCCE AV 600 MHz. The mass spectrum was obtained on a Waters AutoSpec Premier P776. Progress of the reaction was monitored by TLC using sheets precoated with UV fluorescent silica gel Merck 60F 254.

2.1. Preparation of HBOA

To a suspension of 4.0 g FeCl₃·6H₂O in 200 mL methanol, 9.0 g activated carbon was added and refluxed for 30 minutes. 31.0 g 2-nitroresorcinol (0.2 mol) was added and then 36 mL 80% hydrazine hydrate by drops was added in 2 hours. Keep stirring and refluxing for another 4 hours. We filtered all solution to another flask and dried all solvent under vacuum to yield dark syrup. 300 mL butyl acetate and 60.0 g (1 mol) urea were added to the syrup, stirred at 90°C for 5 hours, and then cooled to room temperature. The crude HBOA was obtained by filtration and purified by recrystallization in 80% ethanol (yield 69.5%).

2.2. Preparation of TC-2

Compound TC-2 was prepared via chlorination reaction and TC-3 to TC-4 were prepared via Friedel-Crafts acylation on HBOA. To a solution of 1.51 g (0.01 mol) HBOA in 15 mL glacial acetic acid and 2 mL (0.024 mol) 37% HCl, 1.80 g (0.015 mol) H₂O₂ was added in 30 minutes by drops at 45°C, and then temperature was raised to 80°C and stirred for another 2 hours, cooled to room temperature, filtered, and washed with distilled water to obtain compound TC-2 (Scheme 2).

7-Chloro-4-hydroxy-2-benzoxazolone (TC-2). White solid (yield 61%), m.p. 226~228°C; FT-IR (KBr), υ: 3384 (OH), 3175 (NH), 1748 (C=O), 1625, 1562, 1492, 1467 cm⁻¹; ¹H-NMR (DMSO-d6), δ: 11.90 (1H, s, N-H), 10.38 (1H, s, O-H), 7.07 (1H, d, = 8.52 Hz, 6-ArH), 6.85 (1H, d, = 8.52 Hz, 5-ArH).¹³C-NMR (DMSO-d6), δ154.1 (2-C), 143.4 (4-C), 138.0 (7a-C), 122.4 (6-C), 116.8 (7-C), 112.2 (3a-C), 103.1 (5-C), EI: m/z 185 (M⁺, 100%).

2.3. Preparation of TC-3 to TC-4

To slurry of 1.51 g (0.01 mol) HBOA, 8.0 g (0.06 mol) AlCl₃ in 20 mL 1,2-dichloroethane, and 2 mL nitrobenzene, 0.04 mol acyl chloride was added by drops and stirred at rt. for 1 hour. Then temperature was raised to 80°C and stirred for another 4 hours. The reaction was quenched by cooling to rt. and pouring the slurry into 300 mL ice-cold water. Filtered and recrystallized with 90% ethanol to yield pure compounds TC-3 and TC-4 (Schemes 3 and 4).

7-Acetyl-4-hydroxy-2-benzoxazolone (TC-3). White solid (68%), m.p. 226~228°C; FT-IR (KBr), υ: 3358 (OH), 2983, 2844, 1769 (C=O), 1702 (C=O), 1659, 1625, 1512, 1473, 1427, 1356, cm⁻¹; ¹H-NMR (DMSO-d6), δ: 11.88 (1H, s, N-H), 11.08 (1H, s, O-H), 7.46 (1H, d, = 8.82 Hz, 6-ArH), 6.74 (1H, d, = 8.82 Hz, 5-ArH), 2.65 (3H, s, ); ¹³C-NMR (DMSO-d6), δ: 193.3 (^*COCH₃), 154.5 (2-C), 146.9 (4-C), 144.9 (7a-C), 123.7 (6-C), 118.7 (7-C), 113.6 (3a-C), 111.2 (5-C), 30.2 (CO^*CH₃). EI: m/z 193 (M⁺, 78%).

7-Butyryl-4-hydroxy-2-benzoxazolone (TC-4). White solid (72%), m.p. 168~170; FT-IR (KBr), υ: 3138 (OH), 2964, 2933, 2901, 2875, 1777 (C=O), 1748 (C=O), 1659, 1632, 1494, 1472, 1376, 1237, 1156; ¹H-NMR (DMSO-d6), δ: 11.87 (1H, s, N-H), 10.05 (1H, s, O-H), 7.48 (1H, d, = 8.82 Hz, 6-ArH), 6.75 (1H, d, = 8.82 Hz, 5-ArH), 2.93 (2H, t, = 7.14 Hz, ), 1.64 (2H, m, ), 0.93 (3H, t, = 7.38 Hz, ); ¹³C-NMR (DMSO-d6), δ: 195.7 (^*COCH₂CH₂CH₃), 154.5 (2-C), 146.7 (4-C), 144.7 (7a-C), 126.0 (6-C), 123.6 (7-C), 113.4 (3a-C), 111.3 (5-C), 43.6 (CO^*CH₂CH₂CH₃), 17.4 (), 14.2 (). EI: m/z 221 (M⁺, 45%).

2.4. Preparation of TC-5 to TC-10

Compounds TC-5 to TC-10 were prepared by reaction with corresponding primary amines to afford Schiff Base derivatives. To a solution of 0.01 mol starting material in 300 mL ethanol, 1.5 eq primary amine derivatives were added, refluxed for 3 hours, and then cooled to rt. and filtered and washed with distilled water to yield compounds TC-5~TC-10.

7-(1-(2-Hydroxyethylimino)ethyl)-4-hydroxy-2-benzoxazolone (TC-5). Yellow solid (91%), m.p. 270~271°C; FT-IR (KBr), υ: 3429 (O-H), 2963, 2873, 1757 (C=O), 1635, 1576, 1536, 1444, 1380, 1300, 1286, ¹H-NMR (DMSO-d6), δ: 16.80 (1H, s, N-H), 16.20 (1H, s, C₄-OH), 7.37 (1H, d, = 9.0 Hz, 6-ArH), 6.46 (1H, d, = 9.0 Hz, 5-ArH), 3.69 (7H, m), 3.43 (1H, s); ¹³C-NMR (DMSO-d6), δ: 175.6 (C=N), 161.2 (2-C), 155.0 (4-C), 147.2 (7a-C), 125.0 (6-C), 121.2 (7-C), 113.0 (3a-C), 97.3 (5-C), 60.0 (CN^*CH₂CH₂OH), 48.2 (), 15.2 (^*CH₃). EI: m/z 236 (M⁺, 100%).

7-(1-(2-Hydroxyethylimino)butyl)-4-hydroxy-2-benzoxazolone (TC-6). Light yellow solid (45%), m.p. 255~257°C; FT-IR (KBr), υ: 3431 (O-H), 3323 (N-H), 3027 (=C-H), 2957, 2863, 1751 (C=O), 1634, 1617, 1571, 1441, 1383, 1286, 1072, ¹H-NMR (DMSO-d6), δ: 16.84 (1H, s, N-H), 16.30 (1H, s, C₄-OH), 7.36 (1H, d, = 9.0 Hz, 6-ArH), 6.47 (1H, d, = 9.0 Hz, 5-ArH), 3.70 (4H, m), 3.51 (1H, s), 2.88 (2H, t, = 2.28 Hz), 1.61 (2H, m), 1.04 (3H, d, = 2.28 Hz); ¹³C-NMR (600 MHz, DMSO), δ: 178.2 (^*C=N), 161.6 (2-C), 155.0 (4-C), 147.1 (7a-C), 124.8 (6-C), 121.4 (7-C), 111.8 (3a-C), 97.5 (5-C), 60.1 (CN^*CH₂CH₂OH), 47.9 (), 29.4 (^*CH₂CH₂CH₃), 22.0 (), 14.4 (). EI: m/z 264 (M⁺, 100%).

2-(1-(4-Hydroxy-2-benzoxazolone-7-yl)butylide-neamino)acetic Acid (TC-7). White solid (56%), m.p. 80~182°C; FT-IR (KBr), υ: 3333 (O-H), 3138 (N-H), 2969, 2880, 1740 (C=O), 1721 (C=O), 1625, 1593, 1509, 1425, 1370, 1228, 1057; ¹H-NMR (DMSO-d6), δ: 13.45 (1H, s, COO-H), 11.68 (1H, s, N-H), 8.24 (1H, s, O-H), 7.64 (1H, d, = 9.0 Hz, 6-ArH), 6.45 (1H, d, = 9.0 Hz, 5-ArH), 3.85 (2H, s, ), 2.95 (2H, t, = 7.38 Hz, ), 1.66 (2H, m, ), 0.95 (3H, t, = 7.38 Hz, ); ¹³C-NMR (DMSO-d6)δ: 177.6 (^*COOH), 172.1 (^*C=N), 158.0 (2-C), 156.6 (4-C), 147.1 (7a-C), 128.0 (6-C), 115.1 (7-C), 112.7 (3a-C), 110.1 (5-C), 60.1 (CN^*CH₂COOH), 42.2 (^*CH₂CH₂CH₃), 18.3 (), 14.1 (). EI: m/z 278 (M⁺, 12%).

2-(1-(4-Hydroxy-2-benzoxazolone-7-yl)butylide-neamino)propanoic Acid (TC-8). White solid (56%), m.p. 144~146°C; FT-IR (KBr), υ: 3352 (O-H), 2966, 2937, 2876, 1721 (C=O), 1702 (C=O), 1642, 1605, 1512, 1456, 1383, 1232, 1067, 802; ¹H-NMR (DMSO-d6), δ: 13.49 (1H, s, COO-H), 13.16 (1H, s, N-H), 8.14 (1H, s, O-H), 7.63 (1H, d, = 9.0 Hz, 6-ArH), 6.45 (1H, d, = 9.0 Hz, 5-ArH), 4.19 (1H, q, = 7.2 Hz, CNCH^*(CH₃)COOH), 2.96 (2H, t, = 3.66 Hz, ), 1.65 (2H, m, ), 1.33 (3H, d, = 2.88 Hz, ), 0.95 (3H, t, = 3.60 Hz, ); ¹³C-NMR (600 MHz, DMSO), δ: 195.6 (^*COOH), 176.7 (^*C=N), 154.5 (2-C), 146.7 (4-C), 144.7 (7a-C), 126.0 (6-C), 123.5 (7-C), 113.4 (3a-C), 105.5 (5-C), 60.6 (CN^*CH(CH₃)COOH), 43.5 (^*CH₂CH₂CH₃), 30.0 (), 17.5 (), 14.2 (). m/z 292 (M⁺, 40%).

6-(1-(4-Hydroxy-2-benzoxazolone-7-yl)butylide-neamino)hexanoic Acid (TC-9). Light yellow solid (44%), m.p. 138.5~140°C; FT-IR (KBr), υ: 3368 (O-H), 2962, 2943, 2874, 1732 (C=O), 1707 (C=O), 1637, 1606, 1517, 1465, 1375, 1088, 798; ¹H-NMR (DMSO-d6), δ: 13.51 (1H, s, COO-H), 12.06 (1H, s, N-H), 7.96 (1H, s, O-H), 7.61 (1H, d, = 9.0 Hz, 6-ArH), 6.43 (1H, d, = 9.0 Hz, 5-ArH), 3.11 (2H, t, = 6.84 Hz, ), 2.96 (2H, m, ), 2.21 (2H, t, = 7.38 Hz, ), 1.64 (2H, m, ), 1.52 (2H, m, ), 1.45 (2H, m, ), 1.31 (2H, m, ), 0.93 (3H, t, = 7.38 Hz, ); ¹³C-NMR (DMSO-d6), δ: 174.9 (^*COOH), 172.3 (^*C=N), 158.1 (2-C), 156.0 (4-C), 155.7 (7a-C), 127.5 (6-C), 115.5 (7-C), 112.5 (3a-C), 110.4 (5-C), 59.4 (CN^*CH₂CH₂CH₂CH₂CH₂COOH), 47.7 (), 34.1 (^*CH₂CH₂CH₃), 29.6 (), 26.4 (), 24.7 (), 18.3 (), 14.1 (). m/z 334 (M⁺, 32%).

7-(1-(4-Methoxyphenylimino)butyl)-4-hydroxy-2-benzoxazolone (TC-10). Light yellow solid (52%), m.p. 206~207°C; FT-IR (KBr), υ: 3438 (O-H), 2972, 2876, 2836, 1778 (C=O), 1631, 1608, 1570, 1510, 1442, 1376, 1071, 1034 ((), 850; ¹H-NMR (DMSO-d6), δ: 12.09 (1H, s, N-H), 11.85 (1H, s, O-H), 7.54 (1H, d, = 8.76 Hz, 6-ArH), 7.08 (2H, d, = 8.94 Hz, 3′,5′-ArH), 6.82 (1H, d, = 8.76 Hz, 5-ArH), 6.51 (2H, d, = 8.94 Hz, 2′,6′-ArH), 3.79 (3H, s, ), 2.74 (2H, t, = 5.76 Hz, ), 1.58 (2H, m, ), 0.83 (3H, t, = 7.38 Hz, ); ¹³C-NMR (DMSO-d6), δ: 177.4 (^*C=N), 157.6 (1′-C_Ar), 154.9 (2-C), 151.2 (4-C), 146.9 (7a-C), 137.2 (4′-C_Ar), 124.5 (6-C), 123.6 (3′,5′-C_Ar), 119.6 (7-C), 115.0 (2′,6′-C_Ar), 113.4 (3a-C), 100.5 (5-C), 55.8 (O^*CH₃), 31.1 (^*CH₂CH₂CH₃), 22.6 (), 14.4 () m/z: 326 (M⁺, 38%).

3. Result and Discussion

3.1. Biological Testing

3.1.1. Analgesic Activity

Analgesic activity was examined by using the hot-plate test protocol [8, 9]. 120 Webster mice of both sexes weighing 18–22 g were used for study. All animals were fed diet in pellets following standard good laboratory practices. Mice were divided into 12 groups. All of the compounds and the reference drug were suspended in 0.5% carboxymethyl cellulose (CMC) solution. The first group as negative control received 5% CMC solution and the second group received aspirin (g) as a reference drug, while the other groups received the 10 test compounds. Mice were dropped gently in a dry glass beaker of 1 dm³ capacity maintained at 50.5–55°C. Normal reaction time in seconds for all mice was determined at time intervals of 30, 60, and 90 minutes; this is the interval extending from the instant the mouse reaches the hot beaker till the animal licks its feet or jumps out of the beaker (dose 10 mg/kg). The relative potencies to aspirin (g) were then determined (Table 1). Mice were maintained under 12 h light/dark cycles with controlled temperature (28°C).

HBOA and TC-3, TC-5, TC-7, TC-8, and TC-9 exhibited more petent analgesic than aspirin. Compounds TC-3, TC-8, and TC-9 showed around twice the activity of aspirin after 90 minutes.

3.1.2. Anti-Inflammatory Activity

Anti-inflammatory activity was examined by using carrageenan-induced rat paw edema test [10]. Seventy-two adult Sprague-Dawley rats, weighing 150–180 g, were used. All animals were fed diet in pellets following standard good laboratory practices. The animals were randomly divided into 12 groups of six animals each. All of the compounds and the reference drug were suspended in 0.5% carboxymethyl cellulose (CMC) solution. The standard drug aspirin and the test compounds were given at a dose of 20 mg/kg. After one hour of the administration of the compounds and standard drug, 0.1 mL of 1% carrageenan solution in saline was injected into the subplantar region of the right hind paw of each rat. The right hind paw volume was measured after 3 h of carrageenan treatment by means of plethysmometer.

The test compounds showed anti-inflammatory activity ranging from 10.4% to 56.6%, whereas the standard drug aspirin showed 41.5% inhibition of edema after three hours. Compounds TC-3, TC-5, and TC-8 showed more potent anti-inflammatory activity than aspirin (Table 2).

3.2. Chemistry

In this research, we synthesized compounds TC-2 to TC-10, and their bioactivities were tested by carrageenan-induced rat paw edema and hot-plate test methods. The results show that compounds HBOA and TC-3, TC-5, TC-7, TC-8, and TC-9 are active as analgesic and compounds TC-3, TC-5, and TC-8 are active as anti-inflammatory agent, while the other compounds are poorly active towards the tested organisms.

Conflict of Interests

The authors declare that there is no conflict of interests regarding the publication of this paper.

Authors’ Contribution

Tieyu Chen and Guangjin Zheng have equally contributed to this work.

Acknowledgment

The authors gratefully thank their universities for their equipment and financial support.

Supplementary Materials

The supporting material including all the MS, IR, H¹-NMR, C¹³-NMR spectrum for compounds TC-2 to TC-10 synthesized in this research.

Supplementary Material

References

B.-L. Deng, M. D. Cullen, Z. Zhou et al., “Synthesis and anti-HIV activity of new alkenyldiarylmethane (ADAM) non-nucleoside reverse transcriptase inhibitors (NNRTIs) incorporating benzoxazolone and benzisoxazole rings,” Bioorganic and Medicinal Chemistry, vol. 14, no. 7, pp. 2366–2374, 2006.
View at: Publisher Site | Google Scholar
Y. Ivanova, G. Momekov, O. Petrov, M. Karaivanova, and V. Kalcheva, “Cytotoxic Mannich bases of 6-(3-aryl-2-propenoyl)-2(3H)-benzoxazolones,” European Journal of Medicinal Chemistry, vol. 42, no. 11-12, pp. 1382–1387, 2007.
View at: Publisher Site | Google Scholar
P. Carato, S. Yous, D. Sellier, J. H. Poupaert, N. Lebegue, and P. Berthelot, “Efficient and selective deprotection method for N-protected 2(3H)-benzoxazolones and 2(3H)-benzothiazolones,” Tetrahedron, vol. 60, no. 45, pp. 10321–10324, 2004.
View at: Publisher Site | Google Scholar
K. Shankaran, K. L. Donnelly, S. K. Shah et al., “Inhibition of nitric oxide synthase by benzoxazolones,” Bioorganic and Medicinal Chemistry Letters, vol. 7, no. 22, pp. 2887–2892, 1997.
View at: Publisher Site | Google Scholar
D. D. Erol, M. D. Aytemir, and N. Yuluĝ, “Synthesis and antibacterial and antifungal properties of thiazolinoethyl-2(3H)-benzoxazolone derivatives. II,” European Journal of Medicinal Chemistry, vol. 31, no. 9, pp. 731–734, 1996.
View at: Publisher Site | Google Scholar
L. Tang, W.-H. Ma, Y.-L. Ma, S.-R. Ban, X.-E. Feng, and Q.-S. Li, “Synthesis and biological activity of 4-substituted benzoxazolone derivatives as a new class of sEH inhibitors with high anti-inflammatory activity in vivo,” Bioorganic & Medicinal Chemistry Letters, vol. 23, no. 8, pp. 2380–2383, 2013.
View at: Publisher Site | Google Scholar
L. Tang, S. R. Ban, X. E. Feng, W. H. Lin, and Q. S. Li, “Synthesis and activities of new 4-hydroxy benzoxazolone derivatives,” Chinese Chemical Letters, vol. 21, no. 1, pp. 63–66, 2010.
View at: Publisher Site | Google Scholar
H.-L. Xin, X.-F. Zhai, X. Zheng, L. Zhang, Y.-L. Wang, and Z. Wang, “Anti-inflammatory and analgesic activity of total flavone of Cunninghamia lanceolata,” Molecules, vol. 17, no. 8, pp. 8842–8850, 2012.
View at: Publisher Site | Google Scholar
E. M. Franzotti, C. V. F. Santos, H. M. S. L. Rodrigues, R. H. V. Mourão, M. R. Andrade, and A. R. Antoniolli, “Anti-inflammatory, analgesic activity and acute toxicity of Sida cordifolia L. (Malva-branca),” Journal of Ethnopharmacology, vol. 72, no. 1-2, pp. 273–277, 2000.
View at: Publisher Site | Google Scholar
C. A. Winter, E. A. Risley, and G. W. Nuss, “Carrageenin-induced edema in hind paw of the rat as an assay for antiiflammatory drugs,” Proceedings of the Society for Experimental Biology and Medicine, vol. 111, pp. 544–547, 1962.
View at: Publisher Site | Google Scholar

Copyright

Copyright © 2015 Guangjin Zheng et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

2384

Downloads

1019

Citations