One-pot synthesis of 1,2,4,5-tetra substituted imidazoles using sulfonic acid functionalized silica (SiO2-Pr-SO3H)

Ghodsi Mohammadi Ziarani; Zeinab Dashtianeh; Monireh Shakiba Nahad; Alireza Badiei

doi:10.1016/j.arabjc.2013.11.020

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Original article

8 (

); 692-697

doi:

10.1016/j.arabjc.2013.11.020

One-pot synthesis of 1,2,4,5-tetra substituted imidazoles using sulfonic acid functionalized silica (SiO₂-Pr-SO₃H)

Ghodsi Mohammadi Ziarani^{^a,⁎}, Zeinab Dashtianeh^{^a}, Monireh Shakiba Nahad^{^a}, Alireza Badiei^{^b}

a Department of Chemistry, Alzahra University, P.O. Box 19938939973, Tehran, Iran

b School of Chemistry, College of Science, University of Tehran, P.O. Box 14155-6455, Tehran, Iran

⁎Corresponding author. Tel./fax: +98 21 88041344. gmziarani@hotmail.com (Ghodsi Mohammadi Ziarani), gmohammadi@alzahra.ac.ir (Ghodsi Mohammadi Ziarani),

Received: 2012-10-12, Accepted: 2013-11-16, Published: 2013-09-01

Disclaimer:
This article was originally published by Elsevier and was migrated to Scientific Scholar after the change of Publisher.

Peer review under responsibility of King Saud University.

Abstract

SiO₂-Pr-SO₃H has been used as an efficient catalyst for an improved and rapid synthesis of 1,2,4,5-tetrasubstituted imidazoles, by four-component, one-pot reaction of 1,2-diketones, aryl aldehydes, ammonium acetate and substituted aromatic amines in excellent yields under solvent-free conditions.

Keywords

Sulfonic acid functionalized silica

SiO2-Pr-SO3H

Tetrasubstituted imidazoles

Benzil

1,2-Diketones

One-pot reaction

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1 Introduction

The imidazoles constitute an important class of compounds with profound interest to medicinal chemists, as these compounds exhibit diverse biological properties such as antiallergic, analgesic (Chary et al., 2008), antifungal (Ballard et al., 1988), antibacterial, antiprotozoal, anthelmintic (Venkatesan et al., 2009), anti-tuberculosis, and anti-inflammatory (Gupta et al., 2004). They act as glucagon receptor, kinas inhibitor, antagonist of CB1 cannabinoid (Nshimyumukiza et al., 2010) and possess many other activities (Bellina et al., 2008). A large class of imidazoles emerges as ionic liquid in green chemistry and organometallic catalysis (Zang et al., 2010). They also have optical absorption and bright luminescence (Kumar and Thomas, 2011). They have been applied as ligands in coordination chemistry (Fulwa et al., 2009). They are also an active backbone in existing drugs such as candesartan (Alonen et al., 2008), losartan (Polevaya et al., 2001) and eprosartan (Grange et al., 2008) (Scheme 1).

1,2,4,5-Tetra-substituted imidazoles are synthesized by four-component condensation of a 1,2-diketone, a hydroxyketone or a ketomonoxime with an aldehyde, primary amine and ammonium acetate using HY zeolite (Balalaei and Arabanian, 2000), silica gel/NaHSO₄ (Karimi et al., 2006), HClO₄–SiO₂ (Kantevari et al., 2007), molecular iodine (Kidwai et al., 2007), BF₃–SiO₂ (Sadeghi et al., 2008), InCl₃·3H₂O (Das Sharma et al., 2008), potassium dodecatugstocobaltatetrihydrate (K5CoW₁₂O₄₀·3H₂O) (Nagarapu et al., 2007), and Keggin-type heteropolyacids (Heravi et al., 2007). In addition, they can also be synthesized by N-alkylation of tri-substituted imidazoles (Uçucu et al., 2001), hetero-Cope rearrangement (Lantos et al., 1993), condensation of 1,2-diketone with an aryl nitrile and primary amine under microwave irradiation (Balalaie et al., 2003).

In this paper, we want to report the application of SiO₂-Pr-SO₃H as a highly active heterogeneous solid acid catalyst in the preparation of 1,2,4,5-tetrasubstituted imidazoles.

2 Result and discussion

The condensation reaction of benzil (1), aromatic aldehydes (2), ammonium acetate as ammonia source (3) and substituted amine (4) in the presence of SiO₂-Pr-SO₃H produced 1,2,4,5-tetra-substituted imidazoles (5) in excellent yields under solvent-free conditions at 140 °C (Scheme 2) in 10 min to 2.5 h. The results are demonstrated in Table 1. After completion of the reaction (monitored by TLC), water was added for removing any excess ammonium acetate, then the crude product was dissolved in ethyl acetate and the heterogeneous solid acid catalyst was removed easily by simple filtration, and after cooling of the filtrate, the pure crystals of products were obtained. It can be seen when the electron-withdrawing substituents exist in the aromatic ring of the aldehydes, increased yields of products were observed, whereas the effect was reverse with the electron-donating substituent.

Synthesis of 1,2,4,5-tetra-substituted imidazoles (5) in the presence of SiO2-Pr-SO3H.

For the preparation of catalyst, at first, the surface of silica was grafted with (3-mercapto-propyl)trimethoxysilane (MPTS) and then the thiol functionalities were oxidized into sulfonic acid groups by hydrogen peroxide to give SiO₂-Pr-SO₃H as solid heterogeneous catalyst (Scheme 3) (Mohammadi Ziarani et al., 2011, 2014).

The suggested mechanism for the SiO₂-Pr-SO₃H catalyzed transformation is shown in Scheme 4. Concerning the reaction mechanism, we suggest that initially, the solid acid catalyst protonates the carbonyl group of aromatic aldehyde which then condenses with ammonium acetate and substituted aromatic amine (4) to produce the adduct products (7). Nucleophilic reaction of compound (7) with protonated benzil (1) creates intermediate (8). In the presence of catalyst, ring closure followed by dehydration, gives 1,2,4,5-tetra-substituted imidazoles (5). The product structure was confirmed by IR, ¹H NMR and GC–Mass data.

Proposed mechanism for the synthesis of 1,2,4,5-tetra-substituted imidazoles.

The efficiency of various catalysts in the synthesis of imidazole derivatives has been compared in Table 2. The mentioned method has several advantages, such as excellent yields, simple procedure, and use of an eco-friendly and recyclable catalyst.

Table 2 The efficiency comparison of various catalysts in the synthesis of tetra substituted imidazoles.

Entry	Catalyst	Solvent	Condition	Yield (%)	Time (h)	Year	Refs.
1	BF₃·SiO₂	–	140 °C	80–96	2	2008	Sadeghi et al. (2008)
2	InCl₃·3H₂O	MeOH	r.t.	47–84	6–9	2008	Das Sharma et al. (2008)
3	[(CH2)₄SO₃HMIM]	–	140 °C	85–95	2–2.5	2010	Davoodnia et al. (2010)
4	MCM-41	–	140 °C	74–82	1.92–2.25	2010	Shoar et al. (2010)
5	MCM-41	AcOH	Reflux	75–85	23–35 min	2010	Shoar et al. (2010)
6	p-TsOH	–	140 °C	75–82	1.92–2.17	2010	Shoar et al. (2010)
7	p-TsOH	EtOH	Reflux	73–83	13–23 min	2010	Shoar et al. (2010)
8	–	1-Butyl-3-methylimidazolium bromide	140 °C	82–93	1.5–5	2010	Hasaninejad et al. (2010)
9	–	1-Butyl-3-methylimidazolium Bromide	MW	82–93	3–8 min	2010	Hasaninejad et al. (2010)
10	P₂O₅/SiO₂	–	100 °C	87–98	15–55 min	2011	Shaterian et al. (2011)
11	–	–	140 °C	0	3	2010	Davoodnia et al. (2010)
12	SiO₂-Pr-SO₃H	–	140 °C	85–98	10 min–3 h		This work

[(CH₂)₄SO₃HMIM]: 3-methyl-1-(4-sulfonic acid)-butyl imidazolium hydrogen sulfate.

3 Experimental section: general information

IR spectra were recorded from KBr disk using a FT-IR Bruker Tensor 27 instrument. The NMR was run on a Bruker DPX, 250 MHz. Melting points were measured using the capillary tube method with an electro thermal 9200 apparatus.

3.1

3.1 Preparation of catalyst

To SiO₂ (20 g) in dry toluene (50 ml), (3-mercaptopropyl)trimethoxysilane (25 ml) was added and the reaction mixture was refluxed for 24 h. After this period, the mixture was filtered to obtain 3-mercaptopropylsilica which was washed with acetone and dried. 3-mercaptopropylsilica (MPS) (20 g) was oxidized with H₂O₂ (50 ml) and one drop of H₂SO₄ in methanol (20 ml) for 24 h at room temperature and then the mixture was filtered and washed with H₂O and acetone to obtain SiO₂-Pr-SO₃H catalyst. The modified SiO₂-Pr-SO₃H was dried and used as solid acid catalyst in the synthesis of 1,2,4,5-tetra substituted imidazoles.

3.2

3.2 General procedure for the preparation of 1,2,4,5-tetra substituted imidazoles

The activated SiO₂-Pr-SO₃H (0.02 g), an aromatic aldehyde (2.5 mmol), benzil (2.5 mmol, 0.53 g), aniline or benzylamine (2.5 mmol) and ammonium acetate (7.5 mmol, 0.69 g) were placed in a flask and stirred at 140 °C under solvent free conditions for a suitable time (Table 1). The progress of the reaction was monitored by TLC (n-hexane:EtOAc, 1:4). After completion of the reaction, ethyl acetate was added to the reaction mixture, and the insoluble catalyst was separated by a simple filtration. The solvent of filtrate was evaporated, and pure products were obtained. The crystals of 1,2,4,5-tetra substituted imidazoles appeared after gradual evaporation of solvent at room temperature. The catalyst could be washed subsequently with diluted acid solution, water and then acetone. After drying, it can be reused several times without noticeable loss of reactivity.

3.2.1

3.2.1 1-Benzyl-2-(4-hydroxyphenyl)-4,5-diphenyl imidazole (5f)

IR (KBr): ν_max = 3027, 1583, 1484, 1447; ¹H NMR (250 MHz, CDCl₃) δ_H = 5.08 (s, 2H, CH₂), 6.81–7.60 (m, 19 CH, arom) ppm; Mass (m/e): 402, 385, 325, 133, 77.

3.2.2

3.2.2 1-Benzyl-2-(3,4-dimethoxyphenyl)-4,5-diphenyl imidazole (5j)

IR (KBr): ν_max = 1594, 1479, 1418 cm⁻¹; ¹H NMR (DMSO-d₆) δ = 3.62 (s, 6H, 2CH₃), 5.19 (s, 2H, CH₂), 6.79–7.47 (m, 18H), ppm; Mass (m/e): 461, 430, 385, 339, 282, 165, 136, 91, 55.

4 Conclusion

In summary, we have demonstrated one-pot, four-component synthesis of 1,2,4,5-tetra substituted imidazoles, in the presence of sulfonic acid functionalized silica as an efficient solid acid catalyst in good to excellent yields under solvent free conditions. The attractive merit features of this protocol are the environmentally friendly conditions, simplicity of reaction, reasonable reaction times, very good yields, and simple workup procedure.

Acknowledgments

We gratefully acknowledge the financial support from the Research Council of Alzahra University and the University of Tehran.

References

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Kumar D., Thomas K.R.J., . Optical properties of pyrene and anthracene containing imidazoles: experimental and theoretical investigations. J. Photochem. Photobiol., A. 2011;218:162-173.
[Google Scholar]
Lantos I., Zhang W.Y., Shui X., Eggleston D.S., . Synthesis of imidazoles via hetero-Cope rearrangements. J. Org. Chem.. 1993;58:7092-7095.
[Google Scholar]
Mohammadi Ziarani G., Badiei A., Azizi M., Zarabadi P., . Synthesis of 3,4-dihydropyrano[c]chromene derivatives using sulfonic acid functionalized silica (SiO₂PrSO₃H) Iran J. Chem. Chem. Eng.. 2011;30:59-65.
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Mohammadi Ziarani G., Badiei A., Hassanzadeh M., Mousavi S., . Synthesis of 1,8-dioxo-decahydroacridine derivatives using sulfonic acid functionalized silica (SiO₂-Pr-SO₃H) under solvent free conditions. Arabian J. Chem.. 2014;7:335-339.
[Google Scholar]
Nagarapu L., Apuri S., Kantevari S., . Potassium dodecatugstocobaltate trihydrate (K₅CoW₁₂O₄₀·3H₂O): a mild and efficient reusable catalyst for the one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles under conventional heating and microwave irradiation. J. Mol. Catal. A: Chem.. 2007;266:104-108.
[Google Scholar]
Nshimyumukiza P., Van Den Berge E., Delest B., Mijatovic T., Kiss R., Marchand-Brynaert J., Robiette R., . Synthesis and biological evaluation of novel imidazole-containing macrocycles. Tetrahedron. 2010;66:4515-4520.
[Google Scholar]
Polevaya L., Mavromoustakos T., Zoumboulakis P., Grdadolnik S.G., Roumelioti P., Giatas N., Mutule I., Keivish T., Vlahakos D.V., Iliodromitis E.K., Kremastinos D.T., Matsoukas J., . Synthesis and study of a cyclic angiotensin II antagonist analogue reveals the role of π^*–π^* interactions in the C-terminal aromatic residue for agonist activity and its structure resemblance with AT1 non-peptide antagonists. Bioorg. Med. Chem.. 2001;9:1639-1647.
[Google Scholar]
Sadeghi B., Mirjalili B.B.F., Hashemi M.M., . BF₃·SiO₂: an efficient reagent system for the one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles. Tetrahedron Lett.. 2008;49:2575-2577.
[Google Scholar]
Shaterian H.R., Ranjbar M., Azizi K., . Efficient multi-component synthesis of highly substituted imidazoles utilizing P₂O₅/SiO₂ as a reusable catalyst. Chin. J. Chem.. 2011;29:1635-1645.
[Google Scholar]
Shoar R.H., Rahimzadeh G., Derikvand F., Farzaneh M., . Four-component, one-pot synthesis of tetra-substituted imidazoles using a catalytic amount of MCM-41 or p-TsOH. Synth. Commun.. 2010;40:1270-1275.
[Google Scholar]
Uçucu Ü., Karaburun N.G., Işikdağ İ., . Synthesis and analgesic activity of some 1-benzyl-2-substituted-4,5-diphenyl-1H-imidazole derivatives. IL Farmaco. 2001;56:285-290.
[Google Scholar]
Venkatesan S., Meera K.M., Begum S., . Emulsion liquid membrane pertraction of imidazole from dilute aqueous solutions by Aliquat-336 mobile carrier. Desalination. 2009;236:65-77.
[Google Scholar]
Zang H., Su Q., Mo Y., Cheng B.W., Jun S., . Ionic liquid [EMIM]OAc under ultrasonic irradiation towards the first synthesis of trisubstituted imidazoles. Ultrason. Sonochem.. 2010;17:749-751.
[Google Scholar]

Introduction

Result and discussion

Experimental section: general information

Preparation of catalyst
General procedure for the preparation of 1,2,4,5-tetra substituted imidazoles

Conclusion

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[1] Alonen A., Jansson J., Kallonen S., Kiriazis A., Aitio O., Finel M., Kostiainen R., . Enzyme-assisted synthesis and structure characterization of glucuronic acid conjugates of losartan, candesartan, and zolarsartan. Bioorg. Chem.. 2008;36:148-155.
[Google Scholar]

[2] Balalaei S., Arabanian A., . A. One-pot synthesis of tetrasubstituted imidazoles catalyzed by zeolite HY and silica gel under microwave irradiation. Green Chem.. 2000;2:274-276.
[Google Scholar]

[3] Balalaie S., Hashemi M.M., Akhbari M., . A novel one-pot synthesis of tetrasubstituted imidazoles under solvent-free conditions and microwave irradiation. Tetrahedron Lett.. 2003;44:1709-1711.
[Google Scholar]

[4] Ballard S.A., Lodola A., Tarbit M.H., . A comparative study of 1-substituted imidazole and 1,2,4-triazole antifungal compounds as inhibitors of testosterone hydroxylations catalysed by mouse hepatic microsomal cytochromes P-450. Biochem. Pharmacol.. 1988;37:4643-4651.
[Google Scholar]

[5] Bellina F., Cauteruccio S., Di Fiore A., Marchetti C., Rossi R., . Highly selective synthesis of 4(5)-aryl-,2,4(5)-diaryl-, and 4,5-diaryl-1H-imidazoles via Pd-catalyzed direct C-5 arylation of 1-benzyl-1H-imidazole. Tetrahedron. 2008;64:6060-6072.
[Google Scholar]

[6] Chary M.V., Keerthysri N.C., Vupallapati S.V.N., Lingaiah N., Kantevari S., . Tetrabutylammonium bromide (TBAB) in isopropanol: an efficient, novel, neutral and recyclable catalytic system for the synthesis of 2,4,5-trisubstituted imidazoles. Catal. Commun.. 2008;9:2013-2017.
[Google Scholar]

[7] Das Sharma S., Hazarika P., Konwar D., . An efficient and one-pot synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles catalyzed by InCl₃·3H₂O. Tetrahedron Lett.. 2008;49:2216-2220.
[Google Scholar]

[8] Davoodnia A., Heravi M.M., Safavi-Rad Z., Tavakoli-Hoseini N., . Green, one-pot, solvent-free synthesis of 1,2,4,5-tetrasubstituted imidazoles using a Brønsted acidic ionic liquid as novel and reusable catalyst. Synth. Commun.. 2010;40:2588-2597.
[Google Scholar]

[9] Fulwa V.K., Sahu R., Jena H.S., Manivannan V., . Novel synthesis of 2,4-bis(2-pyridyl)-5-(pyridyl)imidazoles and formation of N-(3-(pyridyl)imidazo[1,5-a]pyridine)picolinamidines: nitrogen-rich ligands. Tetrahedron Lett.. 2009;50:6264-6267.
[Google Scholar]

[10] Grange R.L., Ziogas J., North A.J., Angus J.A., Schiesser C.H., . Selenosartans: novel selenophene analogues of milfasartan and eprosartan. Bioorg. Med. Chem. Lett.. 2008;18:1241-1244.
[Google Scholar]

[11] Gupta P., Hameed S., Jain R., . Ring-substituted imidazoles as a new class of anti-tuberculosis agents. Eur. J. Med. Chem.. 2004;39:805-814.
[Google Scholar]

[12] Hasaninejad A., Zare A., Shekouhy M., Ameri Rad J., . Catalyst-free one-pot four component synthesis of polysubstituted imidazoles in neutral ionic liquid 1-butyl-3-methylimidazolium bromide. J. Comb. Chem.. 2010;12:844-849.
[Google Scholar]

[13] Heravi M.M., Derikvand F., Bamoharram F.F., . Highly efficient, four-component one-pot synthesis of tetrasubstituted imidazoles using Keggin-type heteropolyacids as green and reusable catalysts. J. Mol. Catal. A: Chem.. 2007;263:112-114.
[Google Scholar]

[14] Kantevari S., Vuppalapati S.V.N., Biradar D.O., Nagarapu L., . Highly efficient, one-pot, solvent-free synthesis of tetrasubstituted imidazoles using HClO₄–SiO₂ as novel heterogeneous catalyst. J. Mol. Catal. A: Chem.. 2007;266:109-113.
[Google Scholar]

[15] Karimi A.R., Alimohammadi Z., Azizian J., Mohammadi A.A., Mohammadizadeh M.R., . Solvent-free synthesis of tetrasubstituted imidazoles on silica gel/NaHSO₄ support. Catal. Commun.. 2006;7:728-732.
[Google Scholar]

[16] Kidwai M., Mothsra P., Bansal V., Somvanshi R.K., Ethayathulla A.S., Dey S., Singh T.P., . One-pot synthesis of highly substituted imidazoles using molecular iodine: a versatile catalyst. J. Mol. Catal. A: Chem.. 2007;265:177-182.
[Google Scholar]

[17] Kumar D., Thomas K.R.J., . Optical properties of pyrene and anthracene containing imidazoles: experimental and theoretical investigations. J. Photochem. Photobiol., A. 2011;218:162-173.
[Google Scholar]

[18] Lantos I., Zhang W.Y., Shui X., Eggleston D.S., . Synthesis of imidazoles via hetero-Cope rearrangements. J. Org. Chem.. 1993;58:7092-7095.
[Google Scholar]

[19] Mohammadi Ziarani G., Badiei A., Azizi M., Zarabadi P., . Synthesis of 3,4-dihydropyrano[c]chromene derivatives using sulfonic acid functionalized silica (SiO₂PrSO₃H) Iran J. Chem. Chem. Eng.. 2011;30:59-65.
[Google Scholar]

[20] Mohammadi Ziarani G., Badiei A., Hassanzadeh M., Mousavi S., . Synthesis of 1,8-dioxo-decahydroacridine derivatives using sulfonic acid functionalized silica (SiO₂-Pr-SO₃H) under solvent free conditions. Arabian J. Chem.. 2014;7:335-339.
[Google Scholar]

[21] Nagarapu L., Apuri S., Kantevari S., . Potassium dodecatugstocobaltate trihydrate (K₅CoW₁₂O₄₀·3H₂O): a mild and efficient reusable catalyst for the one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles under conventional heating and microwave irradiation. J. Mol. Catal. A: Chem.. 2007;266:104-108.
[Google Scholar]

[22] Nshimyumukiza P., Van Den Berge E., Delest B., Mijatovic T., Kiss R., Marchand-Brynaert J., Robiette R., . Synthesis and biological evaluation of novel imidazole-containing macrocycles. Tetrahedron. 2010;66:4515-4520.
[Google Scholar]

[23] Polevaya L., Mavromoustakos T., Zoumboulakis P., Grdadolnik S.G., Roumelioti P., Giatas N., Mutule I., Keivish T., Vlahakos D.V., Iliodromitis E.K., Kremastinos D.T., Matsoukas J., . Synthesis and study of a cyclic angiotensin II antagonist analogue reveals the role of π^*–π^* interactions in the C-terminal aromatic residue for agonist activity and its structure resemblance with AT1 non-peptide antagonists. Bioorg. Med. Chem.. 2001;9:1639-1647.
[Google Scholar]

[24] Sadeghi B., Mirjalili B.B.F., Hashemi M.M., . BF₃·SiO₂: an efficient reagent system for the one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles. Tetrahedron Lett.. 2008;49:2575-2577.
[Google Scholar]

[25] Shaterian H.R., Ranjbar M., Azizi K., . Efficient multi-component synthesis of highly substituted imidazoles utilizing P₂O₅/SiO₂ as a reusable catalyst. Chin. J. Chem.. 2011;29:1635-1645.
[Google Scholar]

[26] Shoar R.H., Rahimzadeh G., Derikvand F., Farzaneh M., . Four-component, one-pot synthesis of tetra-substituted imidazoles using a catalytic amount of MCM-41 or p-TsOH. Synth. Commun.. 2010;40:1270-1275.
[Google Scholar]

[27] Uçucu Ü., Karaburun N.G., Işikdağ İ., . Synthesis and analgesic activity of some 1-benzyl-2-substituted-4,5-diphenyl-1H-imidazole derivatives. IL Farmaco. 2001;56:285-290.
[Google Scholar]

[28] Venkatesan S., Meera K.M., Begum S., . Emulsion liquid membrane pertraction of imidazole from dilute aqueous solutions by Aliquat-336 mobile carrier. Desalination. 2009;236:65-77.
[Google Scholar]

[29] Zang H., Su Q., Mo Y., Cheng B.W., Jun S., . Ionic liquid [EMIM]OAc under ultrasonic irradiation towards the first synthesis of trisubstituted imidazoles. Ultrason. Sonochem.. 2010;17:749-751.
[Google Scholar]

Entry	Time (min)	Yield (%)	Mp (°C)	Mp (Lit)
1	25	95	156–158	157–159 Shoar et al. (2010)
2	10	98	248–250	249–250 Shoar et al. (2010)
3	2.5 h	96	181–183	181–183 Shoar et al. (2010)
4	2.5 h	89	189–190	188–190 Shoar et al. (2010)
5	100	94	158–162	163–165 Shoar et al. (2010)
6	3 h	94	132–133	131–132 Davoodnia et al. (2010)
7	2 h	85	149–150	155–157 Uçucu et al. (2001)
8	2 h	92	163–165	163–165 Davoodnia et al. (2010)
9	3 h	88	125–127	128–129 Uçucu et al. (2001)
10	3 h	95	182–184	188–190 Shaterian et al. 2011)