Lamia BOUBAKRI - Academia.edu (original) (raw)
Papers by Lamia BOUBAKRI
European Journal of Chemistry, Sep 30, 2015
The present study is the first investigation of chemical composition, antioxidant and antimicrobi... more The present study is the first investigation of chemical composition, antioxidant and antimicrobial activities of the volatile oils from Salvia sharifii in Tunisia. The obtained results show that essential oils from Tunis locality were most complex and present 35 compounds representing 96.83% of the total oil composition. The major components of the studied oils in this site are Linalool (32.9%) and the green leaf volatiles; hexyl isolaverate (15.4%) and hexyl-2-methyl butanoate (10.9%) were detected as the major constituents of the oil. Considerable levels of antioxidant activities of the investigated essential oils were highlighted. Variations in antioxidant activities may be attributed to the concentrations of major components and the presence of some phenolic compounds like linalool. Our results showed strong activities of the investigated oils against all tested microorganisms. The antimicrobial test results showed that the oils had a great potential antimicrobial activity against all bacteria and fungal strains. Gram-positive bacteria are more sensitive to the investigated oil, with a range of 0.09 to 6.25 µL/mL than Gram-negative bacteria in the range, which is significantly higher from 1.56 to 25.00 µL/mL. The oil showed moderate antioxidant activities, (IC50 = 16.8 µg/mL) but good to moderate antimicrobial activity against most of the tested microorganisms.
Molecules (Basel, Switzerland), Jan 7, 2017
New benzimidazolium salts 1a-c and their palladium bis-N-heterocyclic carbene complexes 2a-c and ... more New benzimidazolium salts 1a-c and their palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c were designed, synthesized and structurally characterized by NMR (1H and 13C), IR, DART-TOF mass spectrometry and elemental analysis. Then these complexes 2-3 were employed in the Suzuki-Miyaura cross-coupling reaction of substituted arenes with phenylboronic acid under mild conditions in toluene and DMF/H2O (1/1) to afford functionalized biaryl derivatives in good to excellent yields. The antibacterial activity of palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c was measured by disc diffusion method against Gram positive and Gram negative bacteria. Compounds 2a, 2c and 3a-c exhibited potential antibacterial activity against four bacterial species among the five used indicator cells. The product 2b inhibits the growth of the all five tested microorganisms. Moreover, the antioxidant activity determination of ...
Ruthenium(II) complexes bearing benzimidazole-based N-heterocyclic carbene (NHC) ligands as potential antimicrobial, antioxidant, enzyme inhibition, and antiproliferative agents
Journal of Coordination Chemistry
Synthesis of novel Ag(I)-N-heterocyclic carbene complexes soluble in both water and dichloromethane and their antimicrobial studies
The interaction of the benzimidazolium salt with Ag<sub>2</sub>O in dichloromethane t... more The interaction of the benzimidazolium salt with Ag<sub>2</sub>O in dichloromethane to prepare novel Ag(I)-<i>N</i>-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by <sup>1</sup>H and <sup>13</sup>C NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.
![Research paper thumbnail of Three‐component, one‐pot synthesis of pyrano[3,2‐c]chromene derivatives catalyzed by ammonium acetate: Synthesis, characterization, cation binding, and biological determination](https://attachments.academia-assets.com/92662255/thumbnails/1.jpg)
](Journal of Heterocyclic Chemistry, 2019
Three-component reaction of arylaldehydes with malononitrile and 4hydroxycoumarine using CH 3 COO... more Three-component reaction of arylaldehydes with malononitrile and 4hydroxycoumarine using CH 3 COONH 4 as a catalyst at reflux was used for the synthesis of novel substituted pyrano[3,2-c]chromene derivatives. The structure of these compounds was assigned by spectroscopic data such as (IR, 1 HNMR, 13 CNMR, and mass spectral data). The cation binding properties of chromene derivatives 4a-c towards Cu 2+ , Ni 2+ , and Zn 2+ were studied in methanol. The results showed that Zn 2+ is the most complexed in this series of cations, and 4c is best complexed with either Ni 2+ and Zn 2+. Antimicrobial properties of new pyrano[3,2-c]chromene derivatives are investigated, the compound 4c presents against Micrococcus luteus LB 14110 an MIC value of 0.0185 mg/mL quite better to that of ampicillin (0.0195 mg/mL) used as standard. Concerning acetylcholinesterase inhibition activity (AChEI), compound 4c presents an interesting AChEI activity with an inhibition of 52%.
RSC Advances, 2019
A series of ruthenium(ii) complexes with N-heterocyclic carbene ligands were successfully synthes... more A series of ruthenium(ii) complexes with N-heterocyclic carbene ligands were successfully synthesized by transmetalation reactions between silver(i) N-heterocyclic carbene complexes and [RuCl2(p-cymene)]2in dichloromethane under Ar conditions.
Journal of Coordination Chemistry, 2019
Pd(II)-bis(NHC) complexes (where NHC ¼ N-heterocyclic carbene) bearing asymmetrically and symmetr... more Pd(II)-bis(NHC) complexes (where NHC ¼ N-heterocyclic carbene) bearing asymmetrically and symmetrically substituted NHC-ligand have been synthesized via deprotonation of 5,6-dimethylbenzimidazolium salts. The NHC precursors have been achieved via the two step N-alkylation of 5,6-dimethylbenzimidazole. The resultant salts were deprotonated with PdCl 2 and K 2 CO 3 in dry THF for 2(a-e). The obtained complexes were identified and characterized by 1 H and 13 C NMR, FT-IR, DART-TOF mass spectrometry and elemental analysis. These new Pd(II)-bis(NHC) complexes were applied as catalyst precursors for Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid to afford the corresponding products in good yields. This catalytic reaction was evaluated in the presence of KOtBu/toluene. The antibacterial activities of 2(a-e) were investigated against Gram (þ)/(À) bacteria using the agar dilution procedure. The antibacterial activities of 2 vary with the nature of the ligands; MIC values of 2(a-e) were determined.
Journal of Coordination Chemistry, 2019
The interaction of the benzimidazolium salt with Ag 2 O in dichloromethane to prepare novel Ag(I)... more The interaction of the benzimidazolium salt with Ag 2 O in dichloromethane to prepare novel Ag(I)-N-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by 1 H and 13 C NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.
Journal of Coordination Chemistry, 2019
New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2... more New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a-e, potassium carbonate (K 2 CO 3) and palladium chloride (PdCl 2) in pyridine (for 3a-e). The catalytic activity of these complexes in a catalytic system including palladium complexes and K 2 CO 3 in DMF-H 2 O was evaluated in Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid. Our novel complexes show excellent catalytic activities with high turnover numbers (TON) and high turnover frequencies (TOF) (e.g., for the Suzuki-Miyaura reaction: TON up to 370 and TOF up to 123.3 h-1). Both benzimidazolium salts 2a-e and complexes 3 have been characterized using spectroscopic data and elemental analysis. The antimicrobial activity of the N-heterocyclic carbene palladium complexes 3a-e varies with the nature of the ligands. Also, the IC 50 values of both, complexes (3a-e) and benzimidazoles 2a-e, have been determined. In addition, the new palladium complexes were screened for their antitumor activity. Complexes 3e and 3d exhibited the highest antitumor effect with IC 50 values 6.85 μg/mL against MCF-7 and 10.75 μg/mL against T47D, respectively.
Transition Metal Chemistry, 2018
The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare ... more The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare unsymmetrical arylpyridine ketones has been carried out using palladium/N-heterocyclic carbene complexes as catalysts prepared in situ. The selectivity and the rate of these reactions are highly dependent on the conditions, i.e., nature of the palladium catalyst precursor, solvent, temperature and CO pressure. The main side-products arise from direct, non-carbonylative cross-coupling. Under the optimum conditions, arylpyridine ketones are recovered in high yields (60-88%). The antibacterial activities of the corresponding benzimidazole salts 2 were tested against Gram positive and negative bacteria using the agar dilution procedure, and their IC50 values have been determined.
Journal of Coordination Chemistry, 2018
A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized a... more A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized and fully characterized by IR, 1 H NMR, 13 C NMR and 31 P NMR spectroscopies, and elemental analysis. The new N-heterocyclic carbene (NHC)-phosphine palladium(II) complexes 3a-h have been easily prepared by the reaction of the corresponding PEPPSI (pyridine-enhanced precatalyst preparation stabilization and initiation) complexes 2a-h and triphenylphosphine in dichloromethane in high yields. These complexes were applied as catalyst precursors which efficiently catalyzed Sonogashira reactions between aryl bromides and phenylacetylene to afford the corresponding products in good yields. The bulky NHC-Pd-PPh 3 complexes 3 were tested against Gram-positive and Gram-negative bacteria to study their biological activity. All the complexes exhibit antibacterial against these organisms. Investigation of the antiacetylcholinesterase activity of the studied complexes showed that compounds 3a and 3b exhibited moderate activity at 100 μg/mL and product 3b is the most active.
New Journal of Chemistry, 2017
A new palladium complex series with N-heterocyclic carbene (NHC), pyridine and phosphine ligands,... more A new palladium complex series with N-heterocyclic carbene (NHC), pyridine and phosphine ligands, PdCl2(L)NHC (2a–c)(L = NHC), PdCl2(L1)NHC(3a–c)(L1 = pyridine), PdCl2(L2)NHC(4a–c)(L2 = triphenylphosphine) was synthesised and fully characterized.
The complexation properties of some coumarin derivatives toward alkali metal, alkaline earth meta... more The complexation properties of some coumarin derivatives toward alkali metal, alkaline earth metal, some transition metal and some heavy metal cations have been investigated in acetonitrile by means of UV spectrophotometry absorption and conductivity. Thus, the stoichiometries of complexes formed and their stability constants were determined by digital processing of data.
![Research paper thumbnail of Novel pyrano[3,2-c]chromene derivatives via a green one-pot three component: Synthesis, characterization , antioxidant, antibacterial and anti-inflammatory activities](https://attachments.academia-assets.com/92662162/thumbnails/1.jpg)
](Mediterranean Journal of Chemistry, 2016
A simple, green, efficient and economical procedure for the synthesis of , pyrano[3,2-c]chromene ... more A simple, green, efficient and economical procedure for the synthesis of , pyrano[3,2-c]chromene derivatives by using a one-pot three-component condensation of 4-Hydroxycoumarin, various arylaldehydes and malonitrile in 1-butyl-3-methylimidazolium triflate as green media is described. This reaction proceeded under mild conditions with the use of an inexpensive and readily available catalyst, high to excellent yields, and simple workup procedure. In addition; the compounds 5 were investigated for anti-oxidant activities by super oxide radical; DPPH (2,2-Diphenyl-1-picrylhydrazyl); and hydroxyl radical scavenging assays; in which most of them displayed significant antioxidant activities. Furthermore; compounds 5 were evaluated for anti-inflammatory activity by indirect haemolytic and lipoxygenase inhibition assays and revealed good activity. Most of the new compounds 5 exhibited moderate antibacterial activity.
European Journal of Chemistry, Sep 30, 2015
The present study is the first investigation of chemical composition, antioxidant and antimicrobi... more The present study is the first investigation of chemical composition, antioxidant and antimicrobial activities of the volatile oils from Salvia sharifii in Tunisia. The obtained results show that essential oils from Tunis locality were most complex and present 35 compounds representing 96.83% of the total oil composition. The major components of the studied oils in this site are Linalool (32.9%) and the green leaf volatiles; hexyl isolaverate (15.4%) and hexyl-2-methyl butanoate (10.9%) were detected as the major constituents of the oil. Considerable levels of antioxidant activities of the investigated essential oils were highlighted. Variations in antioxidant activities may be attributed to the concentrations of major components and the presence of some phenolic compounds like linalool. Our results showed strong activities of the investigated oils against all tested microorganisms. The antimicrobial test results showed that the oils had a great potential antimicrobial activity against all bacteria and fungal strains. Gram-positive bacteria are more sensitive to the investigated oil, with a range of 0.09 to 6.25 µL/mL than Gram-negative bacteria in the range, which is significantly higher from 1.56 to 25.00 µL/mL. The oil showed moderate antioxidant activities, (IC50 = 16.8 µg/mL) but good to moderate antimicrobial activity against most of the tested microorganisms.
Molecules (Basel, Switzerland), Jan 7, 2017
New benzimidazolium salts 1a-c and their palladium bis-N-heterocyclic carbene complexes 2a-c and ... more New benzimidazolium salts 1a-c and their palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c were designed, synthesized and structurally characterized by NMR (1H and 13C), IR, DART-TOF mass spectrometry and elemental analysis. Then these complexes 2-3 were employed in the Suzuki-Miyaura cross-coupling reaction of substituted arenes with phenylboronic acid under mild conditions in toluene and DMF/H2O (1/1) to afford functionalized biaryl derivatives in good to excellent yields. The antibacterial activity of palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c was measured by disc diffusion method against Gram positive and Gram negative bacteria. Compounds 2a, 2c and 3a-c exhibited potential antibacterial activity against four bacterial species among the five used indicator cells. The product 2b inhibits the growth of the all five tested microorganisms. Moreover, the antioxidant activity determination of ...
Ruthenium(II) complexes bearing benzimidazole-based N-heterocyclic carbene (NHC) ligands as potential antimicrobial, antioxidant, enzyme inhibition, and antiproliferative agents
Journal of Coordination Chemistry
Synthesis of novel Ag(I)-N-heterocyclic carbene complexes soluble in both water and dichloromethane and their antimicrobial studies
The interaction of the benzimidazolium salt with Ag<sub>2</sub>O in dichloromethane t... more The interaction of the benzimidazolium salt with Ag<sub>2</sub>O in dichloromethane to prepare novel Ag(I)-<i>N</i>-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by <sup>1</sup>H and <sup>13</sup>C NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.
Journal of Heterocyclic Chemistry, 2019
Three-component reaction of arylaldehydes with malononitrile and 4hydroxycoumarine using CH 3 COO... more Three-component reaction of arylaldehydes with malononitrile and 4hydroxycoumarine using CH 3 COONH 4 as a catalyst at reflux was used for the synthesis of novel substituted pyrano[3,2-c]chromene derivatives. The structure of these compounds was assigned by spectroscopic data such as (IR, 1 HNMR, 13 CNMR, and mass spectral data). The cation binding properties of chromene derivatives 4a-c towards Cu 2+ , Ni 2+ , and Zn 2+ were studied in methanol. The results showed that Zn 2+ is the most complexed in this series of cations, and 4c is best complexed with either Ni 2+ and Zn 2+. Antimicrobial properties of new pyrano[3,2-c]chromene derivatives are investigated, the compound 4c presents against Micrococcus luteus LB 14110 an MIC value of 0.0185 mg/mL quite better to that of ampicillin (0.0195 mg/mL) used as standard. Concerning acetylcholinesterase inhibition activity (AChEI), compound 4c presents an interesting AChEI activity with an inhibition of 52%.
RSC Advances, 2019
A series of ruthenium(ii) complexes with N-heterocyclic carbene ligands were successfully synthes... more A series of ruthenium(ii) complexes with N-heterocyclic carbene ligands were successfully synthesized by transmetalation reactions between silver(i) N-heterocyclic carbene complexes and [RuCl2(p-cymene)]2in dichloromethane under Ar conditions.
Journal of Coordination Chemistry, 2019
Pd(II)-bis(NHC) complexes (where NHC ¼ N-heterocyclic carbene) bearing asymmetrically and symmetr... more Pd(II)-bis(NHC) complexes (where NHC ¼ N-heterocyclic carbene) bearing asymmetrically and symmetrically substituted NHC-ligand have been synthesized via deprotonation of 5,6-dimethylbenzimidazolium salts. The NHC precursors have been achieved via the two step N-alkylation of 5,6-dimethylbenzimidazole. The resultant salts were deprotonated with PdCl 2 and K 2 CO 3 in dry THF for 2(a-e). The obtained complexes were identified and characterized by 1 H and 13 C NMR, FT-IR, DART-TOF mass spectrometry and elemental analysis. These new Pd(II)-bis(NHC) complexes were applied as catalyst precursors for Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid to afford the corresponding products in good yields. This catalytic reaction was evaluated in the presence of KOtBu/toluene. The antibacterial activities of 2(a-e) were investigated against Gram (þ)/(À) bacteria using the agar dilution procedure. The antibacterial activities of 2 vary with the nature of the ligands; MIC values of 2(a-e) were determined.
Journal of Coordination Chemistry, 2019
The interaction of the benzimidazolium salt with Ag 2 O in dichloromethane to prepare novel Ag(I)... more The interaction of the benzimidazolium salt with Ag 2 O in dichloromethane to prepare novel Ag(I)-N-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by 1 H and 13 C NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.
Journal of Coordination Chemistry, 2019
New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2... more New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a-e, potassium carbonate (K 2 CO 3) and palladium chloride (PdCl 2) in pyridine (for 3a-e). The catalytic activity of these complexes in a catalytic system including palladium complexes and K 2 CO 3 in DMF-H 2 O was evaluated in Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid. Our novel complexes show excellent catalytic activities with high turnover numbers (TON) and high turnover frequencies (TOF) (e.g., for the Suzuki-Miyaura reaction: TON up to 370 and TOF up to 123.3 h-1). Both benzimidazolium salts 2a-e and complexes 3 have been characterized using spectroscopic data and elemental analysis. The antimicrobial activity of the N-heterocyclic carbene palladium complexes 3a-e varies with the nature of the ligands. Also, the IC 50 values of both, complexes (3a-e) and benzimidazoles 2a-e, have been determined. In addition, the new palladium complexes were screened for their antitumor activity. Complexes 3e and 3d exhibited the highest antitumor effect with IC 50 values 6.85 μg/mL against MCF-7 and 10.75 μg/mL against T47D, respectively.
Transition Metal Chemistry, 2018
The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare ... more The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare unsymmetrical arylpyridine ketones has been carried out using palladium/N-heterocyclic carbene complexes as catalysts prepared in situ. The selectivity and the rate of these reactions are highly dependent on the conditions, i.e., nature of the palladium catalyst precursor, solvent, temperature and CO pressure. The main side-products arise from direct, non-carbonylative cross-coupling. Under the optimum conditions, arylpyridine ketones are recovered in high yields (60-88%). The antibacterial activities of the corresponding benzimidazole salts 2 were tested against Gram positive and negative bacteria using the agar dilution procedure, and their IC50 values have been determined.
Journal of Coordination Chemistry, 2018
A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized a... more A novel series of N-heterocyclic carbene-phosphine palladium(II) complexes has been synthesized and fully characterized by IR, 1 H NMR, 13 C NMR and 31 P NMR spectroscopies, and elemental analysis. The new N-heterocyclic carbene (NHC)-phosphine palladium(II) complexes 3a-h have been easily prepared by the reaction of the corresponding PEPPSI (pyridine-enhanced precatalyst preparation stabilization and initiation) complexes 2a-h and triphenylphosphine in dichloromethane in high yields. These complexes were applied as catalyst precursors which efficiently catalyzed Sonogashira reactions between aryl bromides and phenylacetylene to afford the corresponding products in good yields. The bulky NHC-Pd-PPh 3 complexes 3 were tested against Gram-positive and Gram-negative bacteria to study their biological activity. All the complexes exhibit antibacterial against these organisms. Investigation of the antiacetylcholinesterase activity of the studied complexes showed that compounds 3a and 3b exhibited moderate activity at 100 μg/mL and product 3b is the most active.
New Journal of Chemistry, 2017
A new palladium complex series with N-heterocyclic carbene (NHC), pyridine and phosphine ligands,... more A new palladium complex series with N-heterocyclic carbene (NHC), pyridine and phosphine ligands, PdCl2(L)NHC (2a–c)(L = NHC), PdCl2(L1)NHC(3a–c)(L1 = pyridine), PdCl2(L2)NHC(4a–c)(L2 = triphenylphosphine) was synthesised and fully characterized.
The complexation properties of some coumarin derivatives toward alkali metal, alkaline earth meta... more The complexation properties of some coumarin derivatives toward alkali metal, alkaline earth metal, some transition metal and some heavy metal cations have been investigated in acetonitrile by means of UV spectrophotometry absorption and conductivity. Thus, the stoichiometries of complexes formed and their stability constants were determined by digital processing of data.
Mediterranean Journal of Chemistry, 2016
A simple, green, efficient and economical procedure for the synthesis of , pyrano[3,2-c]chromene ... more A simple, green, efficient and economical procedure for the synthesis of , pyrano[3,2-c]chromene derivatives by using a one-pot three-component condensation of 4-Hydroxycoumarin, various arylaldehydes and malonitrile in 1-butyl-3-methylimidazolium triflate as green media is described. This reaction proceeded under mild conditions with the use of an inexpensive and readily available catalyst, high to excellent yields, and simple workup procedure. In addition; the compounds 5 were investigated for anti-oxidant activities by super oxide radical; DPPH (2,2-Diphenyl-1-picrylhydrazyl); and hydroxyl radical scavenging assays; in which most of them displayed significant antioxidant activities. Furthermore; compounds 5 were evaluated for anti-inflammatory activity by indirect haemolytic and lipoxygenase inhibition assays and revealed good activity. Most of the new compounds 5 exhibited moderate antibacterial activity.