Document Type : Original Article
Author
Department of Science College of Basic Education, University of Sumer Rifai, Iraq
Abstract
In this study, a derivative of azetidine was obtained by refluxing Schiff-base with an aromatic aldehyde. Schiff-base was prepared by reaction of hydrazine hydrate with chloroacetylchloride without heating. FT-IR and 1H-NMR proved all prepared compounds and chemical structures. The final compound (d), the target of this work, was screened for antioxidant activity and exhibited good results.
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Main Subjects
Introduction
The azetidin-2-one is well known as the [β-lactams] ring of a four-membered cyclic amide it is named due to the N atom, which is linked to β-carbon lined with carbonyl [1]. The history of the azetidine compounds back to 1907, the Schiff base reaction [2] from aniline and aldehyde Cycloaddition reaction. Chemistry of this has a wide spectrum and essential part in organo-synthetic chemistry [3] since the revelation of Alexander Fleming for prepared Penicillin and the need of more active compounds against the activity of bacteria and fungi due to the resistance of the micro-species [4, 5]. The molecular action of the β-lactams derivative antibiotic is power selective and irreversible inhabitation when it is use for processing enzymes of developing peptidoglycan layer [6]. The azetidine-2-one is a very important type of synthetic chemical structure possessing very wide bands of biological activities such as anti-bacterial [7], anti-inflammatory [8], CNS activity, and anti-cancer activity [9] so, which made this type of four-membered structure very strong and widely used for a different type of micro-activity by bacteria or virus which affected the vital cell of human [10].
Materials and Methods
All chemical ingredients were obtained from SD fine chemical Co. All synthesized compounds were purified by recrystallization, and Gallen Kamp capillary melting point was used to calculate melting points. (Bruker) tensor M27 spectrometer was used to predict FT-IR measurements. 1H-NMR spectra appeared in a Bruker spectrophotometer ultra-shield at (400) MHz using DMSO as an internal standard.
Preparation of 2-chloroacetohydrazide (a) [11, 12]
In a round bottom flask, 50 mL supplied with a magnetic stirring bar, hydrazine hydrate 7.5 mL. The round bottom flask was cooled to 5 °C with stirring and added dropwise chloroacetylchloride (1.1 mL). The mixture was stirred 2 hrs under room temperature. Compound (a): Pale yellow, bp 220-225 °C, yield 85%, FT-IR (KBr) (νmax/ cm-1): 3410, 3400, 3288, 2982, 2870, 1625, and 724. 1H-NMR (400 MHz, DMSO): δ 12 (s, 2H, NH2), 11.4 (s, 1H, NH), 7.3-8.1 (m, 4H, ArH).
Preparation of 2-(1H-pyrrol-1-yl) Aceto hydrazide (b) [13, 14]
Pyrrole 10 mL with a few drops of KOH, 2-chloroacetohydrazide (a) 6 mL was added in three portions for one hour with continuous stirring. The mixture refluxed for 4h at 75-85 °C, the mixture was cooled off and concentrated under reduced pressure. The solid obtained was washed with cold water and recrystallized from absolute ethanol. Compound (b): Dark yellow, bp 190-195 °C, yield 75%, FT-IR (KBr) (νmax/ cm-1): 3410, 3401, 3295, 3285, 3051, 2920, 2901, 2870, 1630, and 1100.
Preparation of N'-benzylidene-2-(1H-pyrrol-1-yl) Acetohydrazide(Schiff base) (c) [15, 16]
5.5 g of 2-(1H-pyrrol-1-yl) acetohydrazide (b and benzaldehyde (7 mL, 0.01 mol) in the presence of methanol 30 mL; the contents were refluxed for 3hrs at 70-75 °C. Ice water to the reaction mixture was added. The solid which is formed was dried and recrystallized from ethanol. Compound (c): Brown, mp 194-197 °C, yield 70%, FT-IR (KBr) (νmax/ cm-1): 3240, 3056, 2970, 2825, 1674, 1625, 1430, and 1050. 1H-NMR (400 MHz, DMSO): δ 12 (s, 2H, NH2), 11.4 (s, 1H, NH), 7.3-8.1 (m, 4H, Ar-H), 11.3 (s, 1H, NH), 7.41-8.2 (m, 5H, Ar-H), 6.2 (d, 1H, CH-Ph).
Preparation of N-(3-chloro-2-oxo-4-phenylazetidin-1-yl)-2-(1H-pyrrol-1-yl) Acetamide (d) [17]
To a solution of N'-benzylidene-2-(1H-pyrrol-1-yl) Acetohydrazide (c) (4.6 g) in ethanol 20 mL, triethylamine 1 mL was added to this a solution of chloroacetylchloride (1.13 mL) added drop by drop with vigorous stirring. The mixture was refluxed for up to 3h at 90-100 °C. The solid obtained was filtered several times, and concentrated under reduced pressure, recrystallized from absolute ethanol. Compound (d): Off white, mp 187-190 °C, yield 81%, FT-IR (KBr) (νmax/ cm-1): 3050, 3331, 3290, 2860, 2847, 1670, 1661, and 1350. 1H-NMR (400 MHz, DMSO): δ 11.5 (s, 1H, NH), 7.5-8.07 (m, 5H, Ar-H), 6.4 (d, 1H, CH-Ph), 5.5 (d, 1H, CH-Cl), 4.3 (s, 2H, CH2).
Methanol solutions were prepared at 1000 ppm from the prepared compound (d). Different volumes were prepared at 5, 10, 15, 20, 25 of each methanol, a solution of compound (d) in the separate tubes containing 5 mL of 0.005 % methanol solution of DPPH-free radical. For each test, the solution was prepared in triplicate. The solution was disturbed and stored in the dark for two hours till constant values were obtained. The absorption of the samples was calculated at wavelength 517 nm and recorded. DPPH, root scan activity for each sample, and benchmark were measured by exploiting the chemical, mathematical relation below:
[At] represents the consumption of samples, and [A0] indicates the consumption of the controls. The mean values of three separated samples have been measured for all compounds, and an (Ascorbic acid) has been applied as the standard test. The results showed in the Table 1.
Result and discussion
The substituted acid-hydrazide derivatives were exerted to make the new azetidine-2-one derivative the final compound (d), which included four steps Scheme 1. Stretching band to NH group at 3290-3331 cm-1. Carbonyl at 1670 cm-1. C-H aliphatic at 2847 cm-1. C-H aromatic at 3050 cm-1, were observed in the FT-IR spectra, other stretching-bands were shown. The DPPH-free radical test is established on the capacity of the scavenging ability of antioxidants to the “DPPH-free radical”. These free radicals are reacted with appropriate reducing agents and the electron becomes paired off, and the solution loses its color according to the number of electrons taken up. Results in Table 1 and Figure 1 indicated definite “scavenging activity” of the (d) compound to the DPPH-free radical in contrast with the “Ascorbic acid.” The maximum percentage scavenging effects of (d) compound on (DPPH) at the concentration of 25 μg was 85%.
Table 1: Scavenging % for prepared compound d
Compound |
1000 ppm |
||||||||||||||
5 μL |
10 μL |
15 μL |
20 μL |
25 μL |
|||||||||||
|
Aa |
Ao |
(I%) |
Aa |
Ao |
(I%) |
Aa |
Ao |
(I%) |
Aa |
Ao |
(I%) |
Aa |
Ao |
(I%) |
d |
0.306 |
0.655 |
53 |
0.252 |
0.655 |
62 |
0.191 |
0.655 |
71 |
0.144 |
0.655 |
78 |
0.101 |
0.655 |
85 |
Vit. C |
0.245 |
0.655 |
63 |
0.19 |
0.655 |
71 |
0.121 |
0.655 |
82 |
0.085 |
0.655 |
87 |
0.044 |
0.655 |
93 |
Figure 1: The DPPH-free radical scavenging action of compound d
Scheme 1: All synthesized compounds
Conclusion
In this study, the azetidine-2-one derivative showed antioxidant ability, which is an addition for other activity of this wide spectrum compound like anti-bacterial, anti-fungal and anti-cancer.
Acknowledgments
I would like to extend my sincere appreciation to my colleague Dr. Maithim A. Redha, and thanks to everyone who helped me to complete this research.
Disclosure Statement
No potential conflict of interest was reported by the authors.
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Authors' contributions
All authors contributed to data analysis, drafting, and revising of the paper and agreed to be responsible for all the aspects of this work.
ORCID:
Osama S. Hashim
https://orcid.org/0000-0003-4716-9797
HOW TO CITE THIS ARTICLE
Osama S. Hashim. Synthesis, Characterization of Azetidine Derivative and studying the Antioxidant activity. J. Med. Chem. Sci., 2023, 6(3) 553-558