Synthesis and bioactivity studies of coumarin and its derivatives

Coumarin is a naturally occurring compounds being present in several plants and also can be produced through organic synthetic reactions. In this study, substituted coumarins of 3-acetylcoumarin, 3-acetyl-7-(diethylamino)coumarin, 7-(diethylamino)-3-(1-oxobutyl)coumarin, 3-oxobutyl-3H-naphtho[2,1-b]...

Full description

Saved in:
Bibliographic Details
Main Author: Wong, Kok Tong
Format: Thesis
Language:English
Published: 2013
Subjects:
Online Access:http://eprints.utm.my/id/eprint/42215/5/WongKokTongMFS2013.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-utm-ep.42215
record_format uketd_dc
spelling my-utm-ep.422152017-07-11T00:24:50Z Synthesis and bioactivity studies of coumarin and its derivatives 2013-07 Wong, Kok Tong QK Botany Coumarin is a naturally occurring compounds being present in several plants and also can be produced through organic synthetic reactions. In this study, substituted coumarins of 3-acetylcoumarin, 3-acetyl-7-(diethylamino)coumarin, 7-(diethylamino)-3-(1-oxobutyl)coumarin, 3-oxobutyl-3H-naphtho[2,1-b]pyran-2- one, 6-bromo-3-(1-oxobutyl)coumarin and 8-methoxy-3-(1-oxobutyl)coumarin were synthesized via Knoevenagel condensation reaction of respective 2-hydroxybenzaldehyde derivatives with active methylene group from ethyl acetate or ethyl butyrylacetate under basic condition. Meanwhile, 7-hydroxy-4-methylcoumarin, 4-methyl-2H-benzo[h]chromen-2-one, 7-hydroxy-4,8-dimethylcoumarin, 7-hydroxy- 4-propylcoumarin, 4-propyl-2H-benzo[h]chromen-2-one, 7-hydroxy-8-methyl-4- propylcoumarin and 7,8-dihydroxy-4-propylcoumarin were prepared through Pechmann condensation reaction by the condensation of respective substituted phenol and ß-keto-ester in the presence of sulphuric acid as a catalyst. Futher methylation reaction on 7-hydroxy-4-methylcoumarin with iodomethane catalysed by K2CO3 gave 7-methoxy-4-methylcoumarin. Modification of hydroxyl group of 7,8-dihydroxy-4-propylcoumarin using butyric anhydride and dry pyridine yielded 7,8-bis-(1-oxobutoxy)-4-propylcoumarin. In addition, 7-hydroxy-4,8-dimethylcoumarin was converted to 7-benzyloxy-4,8-dimethylcoumarin through reaction of benzyl chloride in dry acetone. In addition, 7,8-methylenedioxy-4-propylcoumarin undergoes Williamson etherification reaction which involved SN2 mechanism between secondary alkyl halide with potassium salt of a phenoxide. All compounds were characterized by spectroscopic techniques using infrared (IR), proton and carbon nuclear magnetic resonance (1H and 13C NMR), and mass spectrometry (MS). The synthesized compounds were tested for their antioxidant and antibacterial activities. It was found that the hydroxylated coumarin derivatives of 7,8-dihydroxy-4-propylcoumarin were tested positive towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay with IC50 value of 4.09 ?g/mL while other hydroxylated compounds were inactive. The antibacterial activity show that 6-bromo- 3-(1-oxobutyl)coumarin exhibited as strong antibacterial agent against B. subtilis bacteria with MIC value 56.25 ?g/mL. 7,8-Methylenedioxy-4-propylcoumarin showed strong activity to all Gram-positive bacteria. 2013-07 Thesis http://eprints.utm.my/id/eprint/42215/ http://eprints.utm.my/id/eprint/42215/5/WongKokTongMFS2013.pdf application/pdf en public masters Universiti Teknologi Malaysia, Faculty of Science Faculty of Science
institution Universiti Teknologi Malaysia
collection UTM Institutional Repository
language English
topic QK Botany
spellingShingle QK Botany
Wong, Kok Tong
Synthesis and bioactivity studies of coumarin and its derivatives
description Coumarin is a naturally occurring compounds being present in several plants and also can be produced through organic synthetic reactions. In this study, substituted coumarins of 3-acetylcoumarin, 3-acetyl-7-(diethylamino)coumarin, 7-(diethylamino)-3-(1-oxobutyl)coumarin, 3-oxobutyl-3H-naphtho[2,1-b]pyran-2- one, 6-bromo-3-(1-oxobutyl)coumarin and 8-methoxy-3-(1-oxobutyl)coumarin were synthesized via Knoevenagel condensation reaction of respective 2-hydroxybenzaldehyde derivatives with active methylene group from ethyl acetate or ethyl butyrylacetate under basic condition. Meanwhile, 7-hydroxy-4-methylcoumarin, 4-methyl-2H-benzo[h]chromen-2-one, 7-hydroxy-4,8-dimethylcoumarin, 7-hydroxy- 4-propylcoumarin, 4-propyl-2H-benzo[h]chromen-2-one, 7-hydroxy-8-methyl-4- propylcoumarin and 7,8-dihydroxy-4-propylcoumarin were prepared through Pechmann condensation reaction by the condensation of respective substituted phenol and ß-keto-ester in the presence of sulphuric acid as a catalyst. Futher methylation reaction on 7-hydroxy-4-methylcoumarin with iodomethane catalysed by K2CO3 gave 7-methoxy-4-methylcoumarin. Modification of hydroxyl group of 7,8-dihydroxy-4-propylcoumarin using butyric anhydride and dry pyridine yielded 7,8-bis-(1-oxobutoxy)-4-propylcoumarin. In addition, 7-hydroxy-4,8-dimethylcoumarin was converted to 7-benzyloxy-4,8-dimethylcoumarin through reaction of benzyl chloride in dry acetone. In addition, 7,8-methylenedioxy-4-propylcoumarin undergoes Williamson etherification reaction which involved SN2 mechanism between secondary alkyl halide with potassium salt of a phenoxide. All compounds were characterized by spectroscopic techniques using infrared (IR), proton and carbon nuclear magnetic resonance (1H and 13C NMR), and mass spectrometry (MS). The synthesized compounds were tested for their antioxidant and antibacterial activities. It was found that the hydroxylated coumarin derivatives of 7,8-dihydroxy-4-propylcoumarin were tested positive towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay with IC50 value of 4.09 ?g/mL while other hydroxylated compounds were inactive. The antibacterial activity show that 6-bromo- 3-(1-oxobutyl)coumarin exhibited as strong antibacterial agent against B. subtilis bacteria with MIC value 56.25 ?g/mL. 7,8-Methylenedioxy-4-propylcoumarin showed strong activity to all Gram-positive bacteria.
format Thesis
qualification_level Master's degree
author Wong, Kok Tong
author_facet Wong, Kok Tong
author_sort Wong, Kok Tong
title Synthesis and bioactivity studies of coumarin and its derivatives
title_short Synthesis and bioactivity studies of coumarin and its derivatives
title_full Synthesis and bioactivity studies of coumarin and its derivatives
title_fullStr Synthesis and bioactivity studies of coumarin and its derivatives
title_full_unstemmed Synthesis and bioactivity studies of coumarin and its derivatives
title_sort synthesis and bioactivity studies of coumarin and its derivatives
granting_institution Universiti Teknologi Malaysia, Faculty of Science
granting_department Faculty of Science
publishDate 2013
url http://eprints.utm.my/id/eprint/42215/5/WongKokTongMFS2013.pdf
_version_ 1747816717845790720