kengyoon yeong | Universiti Sains Malaysia (original) (raw)
Papers by kengyoon yeong
Medicinal Chemistry Research, 2014
Letters in Organic Chemistry, 2014
ABSTRACT A green and facile method to synthesize diversified 1,2-disubstituted benzimidazoles has... more ABSTRACT A green and facile method to synthesize diversified 1,2-disubstituted benzimidazoles has been developed. The total synthesis was performed at room temperature utilizing water and ethanol as solvents. As aqueous media and ethanol have low toxicity and are easily recyclable, the method presented is very suitable for scale-up production. Furthermore, products were obtained in high yield and easily isolated making this method very practical and attractive.
Letters in Drug Design & Discovery, 2012
ABSTRACT The aim of this work was to synthesize a series of compounds to study their antimycobact... more ABSTRACT The aim of this work was to synthesize a series of compounds to study their antimycobacterial potential. Eight compounds were found to be most active with minimum inhibitory concentration of less than 6μM and were more active than Isoniazid (INH) against Mycobacterium tuberculosis H37Rv (MTB). Compounds with electron withdrawing group substituted on the aryl ring were showing better activity. Among the fifteen newly synthesized compounds, compound 6- methyl-4-(4-nitrophenyl)-2-oxo-N-(pyridin-2-yl)-1,2,3,4tetrahydropyrimidine-5-carboxamide (B) was found to be the most active agent against MTB and INH resistant Mycobacterium tuberculosis (INHR-MTB) with minimum inhibitory concentration of
BioMed Research International, 2013
A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluor... more A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The synthesized compounds were screened for their antimycobacterial activity againstM. tuberculosisH37Rv (MTB-H37Rv) and INH-resistantM. tuberculosis(INHR-MTB) strains using agar dilution method. Three of them displayed good activity with MIC of less than 0.2 μM. Compound ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(4-(5-(4-fluorophenyl)pyridin-3-ylphenyl-1H-benzo[d]imidazole-5-carboxylate (5g) was found to be the most active with MIC of 0.112 μM against MTB-H37Rv and 6.12 μM against INHR-MTB, respectively.
European journal of medicinal chemistry, Jan 18, 2014
Two series of novel benzimidazole derivatives were designed, synthesized and evaluated for their ... more Two series of novel benzimidazole derivatives were designed, synthesized and evaluated for their SIRT1 and SIRT2 inhibitory activity. Among the newly synthesized compounds, compound 4j displayed the best inhibitory activity for SIRT1 (IC50 = 54.21 μM) as well as for SIRT2 (IC50 = 26.85 μM). Cell proliferation assay showed that compound 4j possessed good antitumor activity against three different types of cancer cells derived from colon (HCT-116), breast (MDA-MB-468) and blood-leukemia (CCRF-CEM) with cell viability of 40.0%, 53.2% and 27.2% respectively at 50 μM. Docking analysis of representative compound 4j into SIRT2 indicated that the interaction with receptor was primarily due to hydrogen bonding and π-π stacking interactions.
ChemInform, 2011
ABSTRACT 1,3-Dipolar cycloaddition of azomethine ylides, generated in situ via decarboxylative co... more ABSTRACT 1,3-Dipolar cycloaddition of azomethine ylides, generated in situ via decarboxylative condensation of amino acids (III) or (V) and Isatin, to arylmethyleneindenone (I) provides the novel title spiro-heterocycles (IV) and (VI), respectively.
European Journal of Medicinal Chemistry, 2013
A total of 51 novel benzimidazoles were synthesized by a 4-step reaction starting from basic comp... more A total of 51 novel benzimidazoles were synthesized by a 4-step reaction starting from basic compound 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The structure of the novel benzimidazoles was confirmed by mass spectra as well as (1)H NMR spectroscopic data. Out of the 51 novel synthesized compounds, 42 of them were screened for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv strain using BacTiter-Glo™ Microbial Cell Viability (BTG) method. Results of activity screened using Alamar Blue method was also provided for comparison purposes. Two of the novel benzimidazoles synthesized showed moderately good activity with IC50 of less than 15 μM. Compound 5g, ethyl 2-(4-(trifluoromethyl)phenyl)-1-(2-morpholinoethyl)-1H-benzo[d]imidazole-5-carboxylate, was found to be the most active with IC50 of 11.52 μM.
Bioorganic Chemistry, 2013
Bioorganic & Medicinal Chemistry Letters, 2013
A series of fourteen dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions and... more A series of fourteen dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions and were screened for their antimycobacterial activity against Mycobacterium tuberculosis H(37)Rv in HTS (High Throughput Screen). Most of the compounds showed moderate to good activity with MIC of less than 20 μM. Compound…
Bioorganic & Medicinal Chemistry Letters, 2012
A series of twelve dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions. The ... more A series of twelve dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H(37)Rv and INH resistant M. tuberculosis strains using agar dilution method, four of them showed good activity with MIC of less than 1 μM. Compound…
Bioorganic & Medicinal Chemistry Letters, 2010
Series of pyrolidine analogues were synthesized and examined as acetylcholinesterase (AChE) inhib... more Series of pyrolidine analogues were synthesized and examined as acetylcholinesterase (AChE) inhibitors. Among the compounds, compounds 4k and 6k were the most potent inhibitors of the series. Compound 4k, showed potent inhibitory activity against acetyl cholinesterase enzyme with IC(50) 0.10 μmol/L. Pyrolidine analogues might be potential acetyl cholinesterase agents for AD.
Bioorganic & Medicinal Chemistry Letters, 2011
Hexacyclic derivatives share vital pharmacological properties, considered useful in…
Bioorganic & Medicinal Chemistry, 2014
A total of 15 novel benzimidazole derivatives were designed, synthesized and evaluated for their ... more A total of 15 novel benzimidazole derivatives were designed, synthesized and evaluated for their SIRT1 and SIRT2 inhibitory activity. All compounds showed better inhibition on SIRT2 as compared to SIRT1. Among these, compound 5j displayed the best inhibitory activity for SIRT1 (IC50=58.43μM) as well as for SIRT2 (IC50=45.12μM). Cell cytotoxicity assays also showed that compound 5j possesses good antitumor activity against two different cancer cell lines derived from breast cancer (MCF-7 and MDA-MB-468). A simple structure-activity-relationship (SAR) study of the newly synthesized benzimidazole derivatives was also discussed.
![Research paper thumbnail of Ethyl 2-(4-methoxyphenyl)-1-[3-(2-oxopyrrolidin-1-yl)propyl]-1 H -benzimidazole-5-carboxylate](https://attachments.academia-assets.com/68451815/thumbnails/1.jpg)
](Acta Crystallographica Section E Structure Reports Online, 2012
Symmetry codes: (i) x À 1; y; z; (ii) x þ 1; y; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx; Ày; Àz þ 1.
![Research paper thumbnail of Ethyl 1-[3-(2-oxopyrrolidin-1-yl)propyl]-2-phenyl-1 H -benzimidazole-5-carboxylate](https://attachments.academia-assets.com/68451712/thumbnails/1.jpg)
](Acta Crystallographica Section E Structure Reports Online, 2012
![Research paper thumbnail of Ethyl 2-(1,3-benzodioxol-5-yl)-1-[3-(1 H -imidazol-1-yl)propyl]-1 H -benzimidazole-5-carboxylate](https://attachments.academia-assets.com/68451719/thumbnails/1.jpg)
](Acta Crystallographica Section E Structure Reports Online, 2012
organic compounds o248 Yoon et al. C 23 H 22 N 4 O 4 Acta Cryst. (2012). E68, o247-o248 supplemen... more organic compounds o248 Yoon et al. C 23 H 22 N 4 O 4 Acta Cryst. (2012). E68, o247-o248 supplementary materials supplementary materials sup-1
![Research paper thumbnail of Ethyl 2-(4-hydroxy-3-methoxyphenyl)-1-[3-(2-oxopyrrolidin-1-yl)propyl]-1 H -benzimidazole-5-carboxylate monohydrate](https://attachments.academia-assets.com/68451708/thumbnails/1.jpg)
](Acta Crystallographica Section E Structure Reports Online, 2012
organic compounds o88 Yoon et al. C 24 H 27 N 3 O 5 ÁH 2 O Acta Cryst. (2012). E68, o87-o88 suppl... more organic compounds o88 Yoon et al. C 24 H 27 N 3 O 5 ÁH 2 O Acta Cryst. (2012). E68, o87-o88 supplementary materials supplementary materials sup-1
![Research paper thumbnail of Ethyl 2-(4-nitrophenyl)-1-[3-(2-oxopyrrolidin-1-yl)propyl]-1 H -benzimidazole-5-carboxylate](https://attachments.academia-assets.com/68451716/thumbnails/1.jpg)
](Acta Crystallographica Section E Structure Reports Online, 2012
Symmetry codes: (i) x À 1; y; z; (ii) x þ 1; y; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx; Ày; Àz þ 1.
![Research paper thumbnail of Ethyl 2-[4-(morpholin-4-yl)phenyl]-1-[3-(2-oxopyrrolidin-1-yl)propyl]-1 H -1,3-benzimidazole-5-carboxylate monohydrate](https://attachments.academia-assets.com/68451740/thumbnails/1.jpg)
](Acta Crystallographica Section E Structure Reports Online, 2012
Symmetry codes: (i) Àx; Ày þ 1; Àz; (ii) x; y þ 1; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx þ 1; Ày þ... more Symmetry codes: (i) Àx; Ày þ 1; Àz; (ii) x; y þ 1; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx þ 1; Ày þ 1; Àz þ 1; (v) x; y; z À 1; (vi) Àx þ 1; Ày; Àz À 1; (vii) Àx; Ày; Àz.
Medicinal Chemistry Research, 2014
Letters in Organic Chemistry, 2014
ABSTRACT A green and facile method to synthesize diversified 1,2-disubstituted benzimidazoles has... more ABSTRACT A green and facile method to synthesize diversified 1,2-disubstituted benzimidazoles has been developed. The total synthesis was performed at room temperature utilizing water and ethanol as solvents. As aqueous media and ethanol have low toxicity and are easily recyclable, the method presented is very suitable for scale-up production. Furthermore, products were obtained in high yield and easily isolated making this method very practical and attractive.
Letters in Drug Design & Discovery, 2012
ABSTRACT The aim of this work was to synthesize a series of compounds to study their antimycobact... more ABSTRACT The aim of this work was to synthesize a series of compounds to study their antimycobacterial potential. Eight compounds were found to be most active with minimum inhibitory concentration of less than 6μM and were more active than Isoniazid (INH) against Mycobacterium tuberculosis H37Rv (MTB). Compounds with electron withdrawing group substituted on the aryl ring were showing better activity. Among the fifteen newly synthesized compounds, compound 6- methyl-4-(4-nitrophenyl)-2-oxo-N-(pyridin-2-yl)-1,2,3,4tetrahydropyrimidine-5-carboxamide (B) was found to be the most active agent against MTB and INH resistant Mycobacterium tuberculosis (INHR-MTB) with minimum inhibitory concentration of
BioMed Research International, 2013
A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluor... more A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The synthesized compounds were screened for their antimycobacterial activity againstM. tuberculosisH37Rv (MTB-H37Rv) and INH-resistantM. tuberculosis(INHR-MTB) strains using agar dilution method. Three of them displayed good activity with MIC of less than 0.2 μM. Compound ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(4-(5-(4-fluorophenyl)pyridin-3-ylphenyl-1H-benzo[d]imidazole-5-carboxylate (5g) was found to be the most active with MIC of 0.112 μM against MTB-H37Rv and 6.12 μM against INHR-MTB, respectively.
European journal of medicinal chemistry, Jan 18, 2014
Two series of novel benzimidazole derivatives were designed, synthesized and evaluated for their ... more Two series of novel benzimidazole derivatives were designed, synthesized and evaluated for their SIRT1 and SIRT2 inhibitory activity. Among the newly synthesized compounds, compound 4j displayed the best inhibitory activity for SIRT1 (IC50 = 54.21 μM) as well as for SIRT2 (IC50 = 26.85 μM). Cell proliferation assay showed that compound 4j possessed good antitumor activity against three different types of cancer cells derived from colon (HCT-116), breast (MDA-MB-468) and blood-leukemia (CCRF-CEM) with cell viability of 40.0%, 53.2% and 27.2% respectively at 50 μM. Docking analysis of representative compound 4j into SIRT2 indicated that the interaction with receptor was primarily due to hydrogen bonding and π-π stacking interactions.
ChemInform, 2011
ABSTRACT 1,3-Dipolar cycloaddition of azomethine ylides, generated in situ via decarboxylative co... more ABSTRACT 1,3-Dipolar cycloaddition of azomethine ylides, generated in situ via decarboxylative condensation of amino acids (III) or (V) and Isatin, to arylmethyleneindenone (I) provides the novel title spiro-heterocycles (IV) and (VI), respectively.
European Journal of Medicinal Chemistry, 2013
A total of 51 novel benzimidazoles were synthesized by a 4-step reaction starting from basic comp... more A total of 51 novel benzimidazoles were synthesized by a 4-step reaction starting from basic compound 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The structure of the novel benzimidazoles was confirmed by mass spectra as well as (1)H NMR spectroscopic data. Out of the 51 novel synthesized compounds, 42 of them were screened for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv strain using BacTiter-Glo™ Microbial Cell Viability (BTG) method. Results of activity screened using Alamar Blue method was also provided for comparison purposes. Two of the novel benzimidazoles synthesized showed moderately good activity with IC50 of less than 15 μM. Compound 5g, ethyl 2-(4-(trifluoromethyl)phenyl)-1-(2-morpholinoethyl)-1H-benzo[d]imidazole-5-carboxylate, was found to be the most active with IC50 of 11.52 μM.
Bioorganic Chemistry, 2013
Bioorganic & Medicinal Chemistry Letters, 2013
A series of fourteen dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions and... more A series of fourteen dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions and were screened for their antimycobacterial activity against Mycobacterium tuberculosis H(37)Rv in HTS (High Throughput Screen). Most of the compounds showed moderate to good activity with MIC of less than 20 μM. Compound…
Bioorganic & Medicinal Chemistry Letters, 2012
A series of twelve dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions. The ... more A series of twelve dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H(37)Rv and INH resistant M. tuberculosis strains using agar dilution method, four of them showed good activity with MIC of less than 1 μM. Compound…
Bioorganic & Medicinal Chemistry Letters, 2010
Series of pyrolidine analogues were synthesized and examined as acetylcholinesterase (AChE) inhib... more Series of pyrolidine analogues were synthesized and examined as acetylcholinesterase (AChE) inhibitors. Among the compounds, compounds 4k and 6k were the most potent inhibitors of the series. Compound 4k, showed potent inhibitory activity against acetyl cholinesterase enzyme with IC(50) 0.10 μmol/L. Pyrolidine analogues might be potential acetyl cholinesterase agents for AD.
Bioorganic & Medicinal Chemistry Letters, 2011
Hexacyclic derivatives share vital pharmacological properties, considered useful in…
Bioorganic & Medicinal Chemistry, 2014
A total of 15 novel benzimidazole derivatives were designed, synthesized and evaluated for their ... more A total of 15 novel benzimidazole derivatives were designed, synthesized and evaluated for their SIRT1 and SIRT2 inhibitory activity. All compounds showed better inhibition on SIRT2 as compared to SIRT1. Among these, compound 5j displayed the best inhibitory activity for SIRT1 (IC50=58.43μM) as well as for SIRT2 (IC50=45.12μM). Cell cytotoxicity assays also showed that compound 5j possesses good antitumor activity against two different cancer cell lines derived from breast cancer (MCF-7 and MDA-MB-468). A simple structure-activity-relationship (SAR) study of the newly synthesized benzimidazole derivatives was also discussed.
Acta Crystallographica Section E Structure Reports Online, 2012
Symmetry codes: (i) x À 1; y; z; (ii) x þ 1; y; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx; Ày; Àz þ 1.
Acta Crystallographica Section E Structure Reports Online, 2012
Acta Crystallographica Section E Structure Reports Online, 2012
organic compounds o248 Yoon et al. C 23 H 22 N 4 O 4 Acta Cryst. (2012). E68, o247-o248 supplemen... more organic compounds o248 Yoon et al. C 23 H 22 N 4 O 4 Acta Cryst. (2012). E68, o247-o248 supplementary materials supplementary materials sup-1
Acta Crystallographica Section E Structure Reports Online, 2012
organic compounds o88 Yoon et al. C 24 H 27 N 3 O 5 ÁH 2 O Acta Cryst. (2012). E68, o87-o88 suppl... more organic compounds o88 Yoon et al. C 24 H 27 N 3 O 5 ÁH 2 O Acta Cryst. (2012). E68, o87-o88 supplementary materials supplementary materials sup-1
Acta Crystallographica Section E Structure Reports Online, 2012
Symmetry codes: (i) x À 1; y; z; (ii) x þ 1; y; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx; Ày; Àz þ 1.
Acta Crystallographica Section E Structure Reports Online, 2012
Symmetry codes: (i) Àx; Ày þ 1; Àz; (ii) x; y þ 1; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx þ 1; Ày þ... more Symmetry codes: (i) Àx; Ày þ 1; Àz; (ii) x; y þ 1; z; (iii) Àx þ 1; Ày þ 1; Àz; (iv) Àx þ 1; Ày þ 1; Àz þ 1; (v) x; y; z À 1; (vi) Àx þ 1; Ày; Àz À 1; (vii) Àx; Ày; Àz.