Abdoulaye Gassama - Academia.edu (original) (raw)
Papers by Abdoulaye Gassama
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
HAL (Le Centre pour la Communication Scientifique Directe), Jul 12, 2022
ChemInform, Sep 23, 2010
Six novel twin‐tail amphoteric surfactants (V) and (VII) are readily prepared via a condensation ... more Six novel twin‐tail amphoteric surfactants (V) and (VII) are readily prepared via a condensation reaction of furanone (I) with fatty amines (II).
ChemInform, Jun 20, 2010
4-tetrahydroisoquinolines are prepared diastereoselectively from new chiral isoquinolinium salts ... more 4-tetrahydroisoquinolines are prepared diastereoselectively from new chiral isoquinolinium salts which are readily available by the Zincke procedure starting from isoquinolines and chiral primary amines.
Journal of Chemical Crystallography
Case of charge-assisted hydrogen bonding in the crystal structure of sodium laurate, lauric acid.
World Journal of Pharmaceutical and life sciences, Apr 8, 2005
SYNTHESIS AND EVALUATION OF ANTIMALARIAL ACTIVITY OF CURCUMIN DERIVATIVES. One of the main challe... more SYNTHESIS AND EVALUATION OF ANTIMALARIAL ACTIVITY OF CURCUMIN DERIVATIVES. One of the main challenges in the development of new antimalarial drugs is to achieve a viable lead candidate with good pharmacokinetic properties. Curcumin has a broad range of biological activities, including antimalarial activity. Herein, we report the antimalarial activity of six curcumin derivatives (6-12) and an initial analysis of their pharmacokinetic properties. Five compounds have demonstrated potent activity against the P. falciparum in vitro (IC 50 values ranging from 1.7 to 15.2 μg mL −1), with moderate or low cytotoxicity against the HeLa cell line. The substitution of the carbonyl group in 6 by a 2,4-dinitrophenylhydrazone group (to afford 11) increases the Selective Index. These preliminary results indicate curcumin derivatives as potential antimalarial compounds.
Journal of Pharmaceutical Research International
Introduction: The overall objective of the study was to evaluate the effect on blood glucose of t... more Introduction: The overall objective of the study was to evaluate the effect on blood glucose of the ethyl acetate-butanol fraction (EABF) compounds of the aqueous leaf extract of Dialium guineense (Cesalpiniaceae). Materials and Methods: The powder of D. guineense leaves was subjected to decoction. The aqueous solution was respectively fractionated with ethyl acetate and butanol. The sub-fractions were grouped to form the ethyl acetate-butanol fraction (EABF), enriched in flavonoids and tannins. The condensed tannins of EABF were eliminated under the action of casein, resulting in a condensed tannin-free fraction (EAB-TFF). EABF and EAB-TFF were phytochemically characterized and tested in normo-glycemic rats, a glucose tolerance test and type 2 diabetic rats. Results, Analysis and Discussion: EABF (300 mg/kg, per os) has no significant effect on blood glucose in normo-glycemic rats (0.80±0.12 vs 0.81±0.01 g/L). Under the same conditions, EABF without tannins (EAB-TFF: 300 mg/kg, per...
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
European Scientific Journal, ESJ, 2017
Spondias purpurea L. (Anacardiaceae) is a Senegalese traditional pharmacopoeia plant, which leave... more Spondias purpurea L. (Anacardiaceae) is a Senegalese traditional pharmacopoeia plant, which leaves are used in the treatment of various diseases. The leaves’ ethanolic extract exhibited antihyperglycemic activity on models of temporary hyperglycemia. The tests were performed on normoglycemic rats with a glucose tolerance test. The phytochemical investigation of the leaves resulted in the isolation of four flavonoids (quercetin 9, kaempferol 10, quercetin-3- ß-glucopyranoside 6, kaempferol3-ß-galactopyranoside 8), five phenolic compounds (2,4-dihydroxybenzoic acid 2, 4-hydroxybenzoic acid 5, protocatechic 4-ß-glucoside acid 1, hydroxycynnamic acid 7, 5-caffeoylquinic acid 3) and one tannin (Strictinin 4). The known isolated compounds were characterized by NMR and massspectrometry. The present study constitutes the first phytochemical examination of the leaves and the anti-hyperglycemic activity of the ethanolic extract of Spondias Purpurea L.
Arkivoc, 2012
Recently, we have designed chemical strategies leading to C-6 perfunctionalized linear maltohepta... more Recently, we have designed chemical strategies leading to C-6 perfunctionalized linear maltoheptaose derivatives via the acetolysis of persubstituted -cyclodextrin (-CD) at the 6positions. This approach has now been extended to the synthesis of monofunctionalized maltoheptaose derivatives. This report deals with the regioselectivity of the ring opening of monosubstituted -CD and the use of electrospray ionization tandem mass spectrometry (ESI-MS/MS) to identify the substituted unit. In order to confirm our results, a controlled enzymatic degradation of the resulting derivatives, using the glucoamylase of Aspergillus niger, was performed and monitored by liquid chromatography / electrospray ionization mass spectrometry (LC/ESI-MS).
Advanced Synthesis & Catalysis, 2008
Unprotected alkyl glycosides have been oxidized using air as oxidant and copper(I) chloride/TEMPO... more Unprotected alkyl glycosides have been oxidized using air as oxidant and copper(I) chloride/TEMPO as the catalytic system. The primary hydroxy group in the 6 position is selectively transformed into an aldehyde equivalent. The process was optimized by irradiation with visible light. Without further purification and with high yields, the resulting lactols have been transformed into tetrahydroxyazepane.
The Journal of Organic Chemistry, 2011
Tables with two dimesional NMR Data …………………………………………. S3 Compound 10 …………………………………………. S3 Compoun... more Tables with two dimesional NMR Data …………………………………………. S3 Compound 10 …………………………………………. S3 Compound 19a …………………………………………. S4 Compound 19b …………………………………………. S5 Compound 20a …………………………………………. S6 Compound 20b …………………………………………. S7 Compound 21 …………………………………………. S8 Compound 26 …………………………………………. S9 NOE of compound 26 ………………………………………….
![Research paper thumbnail of Enantioselective Access to Bicyclo[4.2.0]octanes by a Sequence of [2+2] Photocycloaddition/Reduction/Fragmentation](https://attachments.academia-assets.com/86823544/thumbnails/1.jpg)
](Chemistry - A European Journal, 2013
Cyclobutanes are most concisely synthesized by [2+2] cycloaddition reactions upon thermal or phot... more Cyclobutanes are most concisely synthesized by [2+2] cycloaddition reactions upon thermal or photochemical activation. [1] Enantioselective access to chiral cyclobutanes can be achieved either by appropriately modifying the reaction conditions of the [2+2] cycloaddition reaction [2, 3] or by subsequent transformations of a pre-formed cyclobutane. [4] A frequently encountered structural motif, in which a cyclobutane is involved, is the bicycloA C H T U N G T R E N N U N G [4.2.0]octane skeleton of several natural products [5] (Figure 1). Although an intermolecular [2+2] photocycloaddition reaction of enones to form bicycloA C H T U N G T R E N N U N G [4.2.0]octanes is feasible, [6] enantioselective access to this skeleton has only been possible by the use of stoichiometric auxiliaries. [7] An alternative approach, which we have tried to employ for some time, relies on an intramolecular Cu-catalyzed [2+2] photocycloaddition [8] to products of general type A and their subsequent desymmetrization by chiral reagents. [4e, f] However, it turned out to be difficult to perform desymmetrization reactions with Z = CO and only the enzymatic Baeyer-Villiger oxidation of ketone 1 was shown to be a sufficiently enantioselective process (Figure 2). When considering alternative ring-opening procedures, the 1,2-elimination of oxygenbridged products of type B attracted our attention. It was envisaged that enantioselectivity could be achieved by employing precursors, which would facilitate elimination reactions and which would be readily available from furan. Indeed, it has now been found that imides 2 are suitable for this purpose and preliminary results of our experiments in this area are reported herein. To access products 2, a Diels-Alder reaction of imides 3 with furan [9] was followed by a ring-opening metathesis reaction with ethylene (Table 1
Tetrahedron Letters, 1997
Condensations of chiral imines 1 and 4, and chiral enaminoesters 10 and 13, with maleic and citra... more Condensations of chiral imines 1 and 4, and chiral enaminoesters 10 and 13, with maleic and citraconic anhydrides were reported. These experimental outcomes can be rationalized by invoking the compact, endo-approaches of the two reactants 18.
European Journal of Medicinal Plants
Raphionacme vignei E. A. Bruce (Apocynaceae) is a plant of the traditional African pharmacopoeia,... more Raphionacme vignei E. A. Bruce (Apocynaceae) is a plant of the traditional African pharmacopoeia, whose parts are used in the treatment of various pathologies. Water-soaked R. vignei tubers are edible. The objective of this study was to isolate triterpenoids from the acetonic extract of R. vignei tubers, evaluate the analgesic and anti-inflammatory activities of each molecule. The isolated compounds, characterized by NMR and mass spectrometry, is composed of six triterpenoids: beta-amyrin dodecanoate 1(DDQ1), lupeol dodecanoate 2(DDQ2), beta-amyrin acetate 3(DDQ3), lupeol acetate 4(DDQ4), luepol 5(DDQ5) and β-sitosterol 6(DDQ6). These molecules (DDQ2, DDQ3, DDQ4, DDQ5, DDQ6) are anti-inflammatory in carrageenan induced rat paw edema, with better anti-inflammatory power for DDQ2 and DDQ4, which would be related to the presence of acetate function and cycle E. DDQ2 and DDQ4 are also analgesic in acetic acid induced contortions and the removal...
A peptide coupling reaction between L-phenylalanine (L-DOPA) and cinnamic acids derivatives has b... more A peptide coupling reaction between L-phenylalanine (L-DOPA) and cinnamic acids derivatives has been successfully employed for the synthesis of a set of small molecules derived from trans (-) clovamide. The antioxidant activity of these derivative molecules is reported. The antioxydant and antiradical activity were determined using DPPH (2-2-Diphenyl picrylhydrazyl) radical. The molecules which exhibit interesting antioxidant activity were: compound 5 (IC50 =3.46±0.034μg/ml); compound 6 (IC50 =3.04±0.01 μg/ml); compound 7 (IC50 =4.23±0.02 μg/ml); compound 8 (IC50 =5.1±0.061 μg/ml); compound 9 (IC50 =1.55±0.17 μg/ml); compound 10 (IC50 =6.02±0.07 μg/ml) and compound 13 (IC50 =2.49±0.06 μg/ml). These molecules contain polyphenols wich are generally very good antioxidants. Thus, this study showed that compound 9 with an IC50 of 1.55 μg/ml has antioxidant activity close to that of quercetin (IC50 = 1.20μg/ml), a well known antioxidant compound.
A peptide coupling reaction between 1-(R)-phenylethylalanine and cinnamic acid derivatives has be... more A peptide coupling reaction between 1-(R)-phenylethylalanine and cinnamic acid derivatives has been successfully employed for the synthesis of a set of small molecules. The antimalarial activity of these derivative molecules is reported. The compounds have been evaluated against chloroquine-sensitive (3D7) and chloroquineresistant (W2) strains of P. falciparum as well as their cytotoxic activity against HUVEC cells. For 3D7, the most active molecule was compound 8 with IC50 of 23.6 nM comparable to that of chloroquine (18.5 nM). The products were characterized by IR, NMR and MS analysis.
This study was designed to assess phytochemical and antiplasmodial activities of Icacina olivifor... more This study was designed to assess phytochemical and antiplasmodial activities of Icacina oliviformis’s and Spondias purpurea’s extracts. Icacina oliviformis (poiret) Raynal (Icacinaceae) and Spondias purpurea L. (Anacardiaceae) are Senegalese traditional pharmacopoeia plants used to treat various diseases. These plants are used for treating malaria and related conditions in south Senegal.The following phytochemicals were detected into the two species: saponins, alkaloids, sterols, polyterpenes, polyphenols, flavonoids, tannins and free or combined quinones. As regards the evaluation of antiplasmodial activity against P. falciparum 3D7 strain, the ethanolic/water extract of Icacina oliviformis stems (SEWIO) displayed the best activity with an IC50 = 1.80 ± 0.51 μg/mL. Therefore, the same extract exhibits some degree of cytotoxicity with a CC50 = 78.30 ± 2.45 μg/mL. The antiplasmodial activity and the cytotoxicity of Icacina oliviformis’s (stems and roots) and Spondias purpurea’s (lea...
Les jeunes feuilles de Icacina senegalensis Juss (Icacinaceae) recoltees en fevrier 2012 dans l&#... more Les jeunes feuilles de Icacina senegalensis Juss (Icacinaceae) recoltees en fevrier 2012 dans l'enceinte de l'Universite Assaue Seck de Ziguinchor (Senegal) sont mis en decotion pendant 4heures dans des solvants de polarites croissantes (hexane, dichloromethane, ethanol, et eau). Apres evaporation a sec le residu d'ethanol est fractionne par chromatographie sur gel de silice avec deux systemes de solvant: acetate d'ethyle /cyclohexane 7/3 (v/v) et acetate d'ethyle / methanol 9/1 (v/v). La fraction eluee a l'acetate d'ethyle / methanol evaporee a sec est purifiee par HPLC sur colonne en phase inverse (RP18). Deux nouveaux flavones C-glycosides (AG2, AG3) et un trans (S, E)-(-) clovamide AG4 ont ete isoles et caracterises par les methodes spectroscopiques (RMN et Spectrometrie de Masse par Electrospray).
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
HAL (Le Centre pour la Communication Scientifique Directe), Jul 12, 2022
ChemInform, Sep 23, 2010
Six novel twin‐tail amphoteric surfactants (V) and (VII) are readily prepared via a condensation ... more Six novel twin‐tail amphoteric surfactants (V) and (VII) are readily prepared via a condensation reaction of furanone (I) with fatty amines (II).
ChemInform, Jun 20, 2010
4-tetrahydroisoquinolines are prepared diastereoselectively from new chiral isoquinolinium salts ... more 4-tetrahydroisoquinolines are prepared diastereoselectively from new chiral isoquinolinium salts which are readily available by the Zincke procedure starting from isoquinolines and chiral primary amines.
Journal of Chemical Crystallography
Case of charge-assisted hydrogen bonding in the crystal structure of sodium laurate, lauric acid.
World Journal of Pharmaceutical and life sciences, Apr 8, 2005
SYNTHESIS AND EVALUATION OF ANTIMALARIAL ACTIVITY OF CURCUMIN DERIVATIVES. One of the main challe... more SYNTHESIS AND EVALUATION OF ANTIMALARIAL ACTIVITY OF CURCUMIN DERIVATIVES. One of the main challenges in the development of new antimalarial drugs is to achieve a viable lead candidate with good pharmacokinetic properties. Curcumin has a broad range of biological activities, including antimalarial activity. Herein, we report the antimalarial activity of six curcumin derivatives (6-12) and an initial analysis of their pharmacokinetic properties. Five compounds have demonstrated potent activity against the P. falciparum in vitro (IC 50 values ranging from 1.7 to 15.2 μg mL −1), with moderate or low cytotoxicity against the HeLa cell line. The substitution of the carbonyl group in 6 by a 2,4-dinitrophenylhydrazone group (to afford 11) increases the Selective Index. These preliminary results indicate curcumin derivatives as potential antimalarial compounds.
Journal of Pharmaceutical Research International
Introduction: The overall objective of the study was to evaluate the effect on blood glucose of t... more Introduction: The overall objective of the study was to evaluate the effect on blood glucose of the ethyl acetate-butanol fraction (EABF) compounds of the aqueous leaf extract of Dialium guineense (Cesalpiniaceae). Materials and Methods: The powder of D. guineense leaves was subjected to decoction. The aqueous solution was respectively fractionated with ethyl acetate and butanol. The sub-fractions were grouped to form the ethyl acetate-butanol fraction (EABF), enriched in flavonoids and tannins. The condensed tannins of EABF were eliminated under the action of casein, resulting in a condensed tannin-free fraction (EAB-TFF). EABF and EAB-TFF were phytochemically characterized and tested in normo-glycemic rats, a glucose tolerance test and type 2 diabetic rats. Results, Analysis and Discussion: EABF (300 mg/kg, per os) has no significant effect on blood glucose in normo-glycemic rats (0.80±0.12 vs 0.81±0.01 g/L). Under the same conditions, EABF without tannins (EAB-TFF: 300 mg/kg, per...
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
European Scientific Journal, ESJ, 2017
Spondias purpurea L. (Anacardiaceae) is a Senegalese traditional pharmacopoeia plant, which leave... more Spondias purpurea L. (Anacardiaceae) is a Senegalese traditional pharmacopoeia plant, which leaves are used in the treatment of various diseases. The leaves’ ethanolic extract exhibited antihyperglycemic activity on models of temporary hyperglycemia. The tests were performed on normoglycemic rats with a glucose tolerance test. The phytochemical investigation of the leaves resulted in the isolation of four flavonoids (quercetin 9, kaempferol 10, quercetin-3- ß-glucopyranoside 6, kaempferol3-ß-galactopyranoside 8), five phenolic compounds (2,4-dihydroxybenzoic acid 2, 4-hydroxybenzoic acid 5, protocatechic 4-ß-glucoside acid 1, hydroxycynnamic acid 7, 5-caffeoylquinic acid 3) and one tannin (Strictinin 4). The known isolated compounds were characterized by NMR and massspectrometry. The present study constitutes the first phytochemical examination of the leaves and the anti-hyperglycemic activity of the ethanolic extract of Spondias Purpurea L.
Arkivoc, 2012
Recently, we have designed chemical strategies leading to C-6 perfunctionalized linear maltohepta... more Recently, we have designed chemical strategies leading to C-6 perfunctionalized linear maltoheptaose derivatives via the acetolysis of persubstituted -cyclodextrin (-CD) at the 6positions. This approach has now been extended to the synthesis of monofunctionalized maltoheptaose derivatives. This report deals with the regioselectivity of the ring opening of monosubstituted -CD and the use of electrospray ionization tandem mass spectrometry (ESI-MS/MS) to identify the substituted unit. In order to confirm our results, a controlled enzymatic degradation of the resulting derivatives, using the glucoamylase of Aspergillus niger, was performed and monitored by liquid chromatography / electrospray ionization mass spectrometry (LC/ESI-MS).
Advanced Synthesis & Catalysis, 2008
Unprotected alkyl glycosides have been oxidized using air as oxidant and copper(I) chloride/TEMPO... more Unprotected alkyl glycosides have been oxidized using air as oxidant and copper(I) chloride/TEMPO as the catalytic system. The primary hydroxy group in the 6 position is selectively transformed into an aldehyde equivalent. The process was optimized by irradiation with visible light. Without further purification and with high yields, the resulting lactols have been transformed into tetrahydroxyazepane.
The Journal of Organic Chemistry, 2011
Tables with two dimesional NMR Data …………………………………………. S3 Compound 10 …………………………………………. S3 Compoun... more Tables with two dimesional NMR Data …………………………………………. S3 Compound 10 …………………………………………. S3 Compound 19a …………………………………………. S4 Compound 19b …………………………………………. S5 Compound 20a …………………………………………. S6 Compound 20b …………………………………………. S7 Compound 21 …………………………………………. S8 Compound 26 …………………………………………. S9 NOE of compound 26 ………………………………………….
Chemistry - A European Journal, 2013
Cyclobutanes are most concisely synthesized by [2+2] cycloaddition reactions upon thermal or phot... more Cyclobutanes are most concisely synthesized by [2+2] cycloaddition reactions upon thermal or photochemical activation. [1] Enantioselective access to chiral cyclobutanes can be achieved either by appropriately modifying the reaction conditions of the [2+2] cycloaddition reaction [2, 3] or by subsequent transformations of a pre-formed cyclobutane. [4] A frequently encountered structural motif, in which a cyclobutane is involved, is the bicycloA C H T U N G T R E N N U N G [4.2.0]octane skeleton of several natural products [5] (Figure 1). Although an intermolecular [2+2] photocycloaddition reaction of enones to form bicycloA C H T U N G T R E N N U N G [4.2.0]octanes is feasible, [6] enantioselective access to this skeleton has only been possible by the use of stoichiometric auxiliaries. [7] An alternative approach, which we have tried to employ for some time, relies on an intramolecular Cu-catalyzed [2+2] photocycloaddition [8] to products of general type A and their subsequent desymmetrization by chiral reagents. [4e, f] However, it turned out to be difficult to perform desymmetrization reactions with Z = CO and only the enzymatic Baeyer-Villiger oxidation of ketone 1 was shown to be a sufficiently enantioselective process (Figure 2). When considering alternative ring-opening procedures, the 1,2-elimination of oxygenbridged products of type B attracted our attention. It was envisaged that enantioselectivity could be achieved by employing precursors, which would facilitate elimination reactions and which would be readily available from furan. Indeed, it has now been found that imides 2 are suitable for this purpose and preliminary results of our experiments in this area are reported herein. To access products 2, a Diels-Alder reaction of imides 3 with furan [9] was followed by a ring-opening metathesis reaction with ethylene (Table 1
Tetrahedron Letters, 1997
Condensations of chiral imines 1 and 4, and chiral enaminoesters 10 and 13, with maleic and citra... more Condensations of chiral imines 1 and 4, and chiral enaminoesters 10 and 13, with maleic and citraconic anhydrides were reported. These experimental outcomes can be rationalized by invoking the compact, endo-approaches of the two reactants 18.
European Journal of Medicinal Plants
Raphionacme vignei E. A. Bruce (Apocynaceae) is a plant of the traditional African pharmacopoeia,... more Raphionacme vignei E. A. Bruce (Apocynaceae) is a plant of the traditional African pharmacopoeia, whose parts are used in the treatment of various pathologies. Water-soaked R. vignei tubers are edible. The objective of this study was to isolate triterpenoids from the acetonic extract of R. vignei tubers, evaluate the analgesic and anti-inflammatory activities of each molecule. The isolated compounds, characterized by NMR and mass spectrometry, is composed of six triterpenoids: beta-amyrin dodecanoate 1(DDQ1), lupeol dodecanoate 2(DDQ2), beta-amyrin acetate 3(DDQ3), lupeol acetate 4(DDQ4), luepol 5(DDQ5) and β-sitosterol 6(DDQ6). These molecules (DDQ2, DDQ3, DDQ4, DDQ5, DDQ6) are anti-inflammatory in carrageenan induced rat paw edema, with better anti-inflammatory power for DDQ2 and DDQ4, which would be related to the presence of acetate function and cycle E. DDQ2 and DDQ4 are also analgesic in acetic acid induced contortions and the removal...
A peptide coupling reaction between L-phenylalanine (L-DOPA) and cinnamic acids derivatives has b... more A peptide coupling reaction between L-phenylalanine (L-DOPA) and cinnamic acids derivatives has been successfully employed for the synthesis of a set of small molecules derived from trans (-) clovamide. The antioxidant activity of these derivative molecules is reported. The antioxydant and antiradical activity were determined using DPPH (2-2-Diphenyl picrylhydrazyl) radical. The molecules which exhibit interesting antioxidant activity were: compound 5 (IC50 =3.46±0.034μg/ml); compound 6 (IC50 =3.04±0.01 μg/ml); compound 7 (IC50 =4.23±0.02 μg/ml); compound 8 (IC50 =5.1±0.061 μg/ml); compound 9 (IC50 =1.55±0.17 μg/ml); compound 10 (IC50 =6.02±0.07 μg/ml) and compound 13 (IC50 =2.49±0.06 μg/ml). These molecules contain polyphenols wich are generally very good antioxidants. Thus, this study showed that compound 9 with an IC50 of 1.55 μg/ml has antioxidant activity close to that of quercetin (IC50 = 1.20μg/ml), a well known antioxidant compound.
A peptide coupling reaction between 1-(R)-phenylethylalanine and cinnamic acid derivatives has be... more A peptide coupling reaction between 1-(R)-phenylethylalanine and cinnamic acid derivatives has been successfully employed for the synthesis of a set of small molecules. The antimalarial activity of these derivative molecules is reported. The compounds have been evaluated against chloroquine-sensitive (3D7) and chloroquineresistant (W2) strains of P. falciparum as well as their cytotoxic activity against HUVEC cells. For 3D7, the most active molecule was compound 8 with IC50 of 23.6 nM comparable to that of chloroquine (18.5 nM). The products were characterized by IR, NMR and MS analysis.
This study was designed to assess phytochemical and antiplasmodial activities of Icacina olivifor... more This study was designed to assess phytochemical and antiplasmodial activities of Icacina oliviformis’s and Spondias purpurea’s extracts. Icacina oliviformis (poiret) Raynal (Icacinaceae) and Spondias purpurea L. (Anacardiaceae) are Senegalese traditional pharmacopoeia plants used to treat various diseases. These plants are used for treating malaria and related conditions in south Senegal.The following phytochemicals were detected into the two species: saponins, alkaloids, sterols, polyterpenes, polyphenols, flavonoids, tannins and free or combined quinones. As regards the evaluation of antiplasmodial activity against P. falciparum 3D7 strain, the ethanolic/water extract of Icacina oliviformis stems (SEWIO) displayed the best activity with an IC50 = 1.80 ± 0.51 μg/mL. Therefore, the same extract exhibits some degree of cytotoxicity with a CC50 = 78.30 ± 2.45 μg/mL. The antiplasmodial activity and the cytotoxicity of Icacina oliviformis’s (stems and roots) and Spondias purpurea’s (lea...
Les jeunes feuilles de Icacina senegalensis Juss (Icacinaceae) recoltees en fevrier 2012 dans l&#... more Les jeunes feuilles de Icacina senegalensis Juss (Icacinaceae) recoltees en fevrier 2012 dans l'enceinte de l'Universite Assaue Seck de Ziguinchor (Senegal) sont mis en decotion pendant 4heures dans des solvants de polarites croissantes (hexane, dichloromethane, ethanol, et eau). Apres evaporation a sec le residu d'ethanol est fractionne par chromatographie sur gel de silice avec deux systemes de solvant: acetate d'ethyle /cyclohexane 7/3 (v/v) et acetate d'ethyle / methanol 9/1 (v/v). La fraction eluee a l'acetate d'ethyle / methanol evaporee a sec est purifiee par HPLC sur colonne en phase inverse (RP18). Deux nouveaux flavones C-glycosides (AG2, AG3) et un trans (S, E)-(-) clovamide AG4 ont ete isoles et caracterises par les methodes spectroscopiques (RMN et Spectrometrie de Masse par Electrospray).