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.
The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column chromato... more The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column chromatography and some pure compounds were obtained whose structures were determined by 1 H and 13 C-NMR spectroscopy. The extract was tested in vitro for anti-onchocercal activity against O. ochengi , a close relative of O. vulvolus . The MeOH extract showed 100% inhibition of O. ochengi microfilarial activity. Compounds 1 , 2 and 3 which were identified as (Z)-12-heptadecenoic acid ( 1 ), hexadecanoic acid ( 2 ) and â-stigmasterol ( 3 ) showed no anti-onchocercal activity against the microfilariae, but 1 and 2 showed weak antibacterial activity against E. coli with erythromycin included as reference.The present study constitutes the first report on the antifilarial activity of Anchomanes difformis and lends credence to the traditional use of juice from the rhizome in the management of river blindness. Key words: Anchomanes difformis, Onchocerciasis, Antibacterial, Antifilarial
ABSTRACT The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column... more ABSTRACT The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column chromatography and some pure compounds were obtained whose structures were determined by 1H and 13C-NMR spectroscopy. The extract was tested in vitro for anti-onchocercal activity against O. ochengi, a close relative of O. vulvolus. The MeOH extract showed 100% inhibition of O. ochengi microfilarial activity. Compounds 1, 2 and 3 which were identified as (Z)-12-heptadecenoic acid (1), hexadecanoic acid (2) and β-stigmasterol ( 3) showed no anti-onchocercal activity against the microfilariae, but 1 and 2 showed weak antibacterial activity against E. coli with erythromycin included as reference.The present study constitutes the first report on the antifilarial activity of Anchomanes difformis and lends credence to the traditional use of juice from the rhizome in the management of river blindness. Key words: Anchomanes difformis, Onchocerciasis, Antibacterial, Antifilarial
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.
International Research Journal of Pure and Applied Chemistry, 2016
Aims: To synthesize some isoniazid-derived imines by the condensation of isoniazid (INH) with som... more Aims: To synthesize some isoniazid-derived imines by the condensation of isoniazid (INH) with some substituted benzaldehydes as well as pyridine carboxaldehydes and to determine their structures by spectroscopic methods. Methodology: Isoniazid was mixed with equimolar amounts of some substituted benzaldehyes as well as pyridine carboxaldehydes and refluxed for 4-7 hours. The solid products were filtered by gravity and dried over anhydrous CaCl2 in a desiccator. The ligands were screened for the biological activities against Salmonella typhi, Staphylococcus aureus, Escherichia coli, Shiegellaflexneri, and Salmonella enterica by paper disc diffusion method. Results: Nine Schiff bases were synthesized and characterized by elemental analyses, 1H NMR, and13C NMR. Their melting temperatures were determined and their purity ascertained by HPLC. Conclusion: Nine isoniazid-derivedimines were synthesized and characterized. The antibacterial activities of some of the imines were comparable to the activity of isoniazid against E. coli, whereas the other Schiff bases were more active than isoniazid against the other tested pathogens. Compound 7 showed good antibacterial activity compared to isoniazid against all the tested pathogens and compound 4 was inactive against all pathogens.
Acta Crystallographica Section E Crystallographic Communications
The title compound, C14H12N4S, was synthesized by the condensation reaction of hydralazine and 2-... more The title compound, C14H12N4S, was synthesized by the condensation reaction of hydralazine and 2-acetylthiophene and during the reaction, a proton transfer from the imino nitrogen atom to one of the endocylic nitrogen atoms occurred. The compound crystallizes in the monoclinic crystal system with two independent molecules (molecules 1 and 2) in the asymmetric unit. In each molecule, there is a slight difference in the orientation of the thiophene ring with respect to phthalazine ring system, molecule 1 showing a dihedral angle of 42.51 (1)° compared to 8.48 (1)° in molecule 2. This implies an r.m.s deviation of 0.428 (1) Å between the two molecules for the 19 non-H atoms. The two independent molecules are connected via two N—H...N hydrogen bonds, forming dimers which interact by two bifurcated π–π stacking interactions to build tetrameric motifs. The latter are packed in the ac plane via weak C—H...π interactions and along the b axis via C—H ...N and C—H...π interactions. This resul...
Natural products (NPs) are often regarded as sources of drugs or drug leads or simply as a "... more Natural products (NPs) are often regarded as sources of drugs or drug leads or simply as a "source of inspiration" for the discovery of novel drugs. We have built the Northern African Natural Products Database (NANPDB) by collecting information on ∼4500 NPs, covering literature data for the period from 1962 to 2016. The data cover compounds isolated mainly from plants, with contributions from some endophyte, animal (e.g., coral), fungal, and bacterial sources. The compounds were identified from 617 source species, belonging to 146 families. Computed physicochemical properties, often used to predict drug metabolism and pharmacokinetics, as well as predicted toxicity information, have been included for each compound in the data set. This is the largest collection of annotated natural compounds produced by native organisms from Northern Africa. While the database includes well-known drugs and drug leads, the medical potential of a majority of the molecules is yet to be invest...
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.
The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column chromato... more The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column chromatography and some pure compounds were obtained whose structures were determined by 1 H and 13 C-NMR spectroscopy. The extract was tested in vitro for anti-onchocercal activity against O. ochengi , a close relative of O. vulvolus . The MeOH extract showed 100% inhibition of O. ochengi microfilarial activity. Compounds 1 , 2 and 3 which were identified as (Z)-12-heptadecenoic acid ( 1 ), hexadecanoic acid ( 2 ) and â-stigmasterol ( 3 ) showed no anti-onchocercal activity against the microfilariae, but 1 and 2 showed weak antibacterial activity against E. coli with erythromycin included as reference.The present study constitutes the first report on the antifilarial activity of Anchomanes difformis and lends credence to the traditional use of juice from the rhizome in the management of river blindness. Key words: Anchomanes difformis, Onchocerciasis, Antibacterial, Antifilarial
ABSTRACT The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column... more ABSTRACT The methanol (MeOH) extract of Anchomanes difformis (Araceae) was fractionated by column chromatography and some pure compounds were obtained whose structures were determined by 1H and 13C-NMR spectroscopy. The extract was tested in vitro for anti-onchocercal activity against O. ochengi, a close relative of O. vulvolus. The MeOH extract showed 100% inhibition of O. ochengi microfilarial activity. Compounds 1, 2 and 3 which were identified as (Z)-12-heptadecenoic acid (1), hexadecanoic acid (2) and β-stigmasterol ( 3) showed no anti-onchocercal activity against the microfilariae, but 1 and 2 showed weak antibacterial activity against E. coli with erythromycin included as reference.The present study constitutes the first report on the antifilarial activity of Anchomanes difformis and lends credence to the traditional use of juice from the rhizome in the management of river blindness. Key words: Anchomanes difformis, Onchocerciasis, Antibacterial, Antifilarial
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.
International Research Journal of Pure and Applied Chemistry, 2016
Aims: To synthesize some isoniazid-derived imines by the condensation of isoniazid (INH) with som... more Aims: To synthesize some isoniazid-derived imines by the condensation of isoniazid (INH) with some substituted benzaldehydes as well as pyridine carboxaldehydes and to determine their structures by spectroscopic methods. Methodology: Isoniazid was mixed with equimolar amounts of some substituted benzaldehyes as well as pyridine carboxaldehydes and refluxed for 4-7 hours. The solid products were filtered by gravity and dried over anhydrous CaCl2 in a desiccator. The ligands were screened for the biological activities against Salmonella typhi, Staphylococcus aureus, Escherichia coli, Shiegellaflexneri, and Salmonella enterica by paper disc diffusion method. Results: Nine Schiff bases were synthesized and characterized by elemental analyses, 1H NMR, and13C NMR. Their melting temperatures were determined and their purity ascertained by HPLC. Conclusion: Nine isoniazid-derivedimines were synthesized and characterized. The antibacterial activities of some of the imines were comparable to the activity of isoniazid against E. coli, whereas the other Schiff bases were more active than isoniazid against the other tested pathogens. Compound 7 showed good antibacterial activity compared to isoniazid against all the tested pathogens and compound 4 was inactive against all pathogens.
Acta Crystallographica Section E Crystallographic Communications
The title compound, C14H12N4S, was synthesized by the condensation reaction of hydralazine and 2-... more The title compound, C14H12N4S, was synthesized by the condensation reaction of hydralazine and 2-acetylthiophene and during the reaction, a proton transfer from the imino nitrogen atom to one of the endocylic nitrogen atoms occurred. The compound crystallizes in the monoclinic crystal system with two independent molecules (molecules 1 and 2) in the asymmetric unit. In each molecule, there is a slight difference in the orientation of the thiophene ring with respect to phthalazine ring system, molecule 1 showing a dihedral angle of 42.51 (1)° compared to 8.48 (1)° in molecule 2. This implies an r.m.s deviation of 0.428 (1) Å between the two molecules for the 19 non-H atoms. The two independent molecules are connected via two N—H...N hydrogen bonds, forming dimers which interact by two bifurcated π–π stacking interactions to build tetrameric motifs. The latter are packed in the ac plane via weak C—H...π interactions and along the b axis via C—H ...N and C—H...π interactions. This resul...
Natural products (NPs) are often regarded as sources of drugs or drug leads or simply as a "... more Natural products (NPs) are often regarded as sources of drugs or drug leads or simply as a "source of inspiration" for the discovery of novel drugs. We have built the Northern African Natural Products Database (NANPDB) by collecting information on ∼4500 NPs, covering literature data for the period from 1962 to 2016. The data cover compounds isolated mainly from plants, with contributions from some endophyte, animal (e.g., coral), fungal, and bacterial sources. The compounds were identified from 617 source species, belonging to 146 families. Computed physicochemical properties, often used to predict drug metabolism and pharmacokinetics, as well as predicted toxicity information, have been included for each compound in the data set. This is the largest collection of annotated natural compounds produced by native organisms from Northern Africa. While the database includes well-known drugs and drug leads, the medical potential of a majority of the molecules is yet to be invest...
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Papers by Joseph Yong
Methodology: Isoniazid was mixed with equimolar amounts of some substituted benzaldehyes as well as pyridine carboxaldehydes and refluxed for 4-7 hours. The solid products were filtered by gravity and dried over anhydrous CaCl2 in a desiccator. The ligands were screened for the biological activities against Salmonella typhi, Staphylococcus aureus, Escherichia coli, Shiegellaflexneri, and Salmonella enterica by paper disc diffusion method.
Results: Nine Schiff bases were synthesized and characterized by elemental analyses, 1H NMR, and13C NMR. Their melting temperatures were determined and their purity ascertained by HPLC.
Conclusion: Nine isoniazid-derivedimines were synthesized and characterized. The antibacterial activities of some of the imines were comparable to the activity of isoniazid against E. coli, whereas the other Schiff bases were more active than isoniazid against the other tested pathogens. Compound 7 showed good antibacterial activity compared to isoniazid against all the tested pathogens and compound 4 was inactive against all pathogens.
Methodology: Isoniazid was mixed with equimolar amounts of some substituted benzaldehyes as well as pyridine carboxaldehydes and refluxed for 4-7 hours. The solid products were filtered by gravity and dried over anhydrous CaCl2 in a desiccator. The ligands were screened for the biological activities against Salmonella typhi, Staphylococcus aureus, Escherichia coli, Shiegellaflexneri, and Salmonella enterica by paper disc diffusion method.
Results: Nine Schiff bases were synthesized and characterized by elemental analyses, 1H NMR, and13C NMR. Their melting temperatures were determined and their purity ascertained by HPLC.
Conclusion: Nine isoniazid-derivedimines were synthesized and characterized. The antibacterial activities of some of the imines were comparable to the activity of isoniazid against E. coli, whereas the other Schiff bases were more active than isoniazid against the other tested pathogens. Compound 7 showed good antibacterial activity compared to isoniazid against all the tested pathogens and compound 4 was inactive against all pathogens.