Willifred Dongmo Tékapi Tsopgni

Willifred Dongmo Tékapi Tsopgni

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 November 2022 in Journal of Chemistry
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LDLiliane Clotilde Dzouemo
Liliane Clotilde Dzouemo
GHGervais Mouthé Happi
Gervais Mouthé Happi
SASikiru Akinyeye Ahmed
Sikiru Akinyeye Ahmed
WTWillifred Dongmo Tékapi Tsopgni
Willifred Dongmo Tékapi Tsopgni
MAMichael Nde Akuma
Michael Nde Akuma
JWJean Duplex Wansi
Jean Duplex Wansi
The phytochemical investigations of the methanol extract of Zanthoxylum gilletii bark led to the isolation of thirteen compounds identified as two alkaloids including one acridone 5-hydroxynoracronycine (1) and one benzo [c] phenanthridine decarine (2), three lignans trans- and cis-fagaramide (3 and 4) and sesamin (5), two coumarins scoparone (6) and scopoletin (7), three pentacyclic triterpenoids fridelin (8), lupeol (9) and erythrodiol-3-O-palmitate (10), one phenolic compound vanillic acid (11) as well as two common steroids stigmasterol (12), and its derivative stigmasterol-3-O-β-D-glucopyranoside (13). The structures of all the isolated compounds were elucidated by means of their spectroscopic and spectrometric data (1D, 2D-NMR, MS) as well as the comparison of these data with those reported in the literature. Except for compounds 9 and 1113, all the other isolated compounds are reported for the first time from Z. gilletii but have been already obtained from other Zanthoxylum species and in the Rutaceae family. Compounds 1, 35, and 9 were tested in vitro for their antiplasmodial potencies against Plasmodium falciparum 3D7, and the results revealed that all the tested compounds displayed an inhibition between 51.89 and 54.69 while only the mixture of 3+4 gave an IC50 lower than 10 000nM (IC50=1333nM). Furthermore, all the compounds have been evaluated in silico for their ability to inhibit the Plasmodium falciparum dihydroorotate dehydrogenase 5TBO. Sesamin (5) showed the greatest affinity to the antiplasmodium receptor than artemether® and chloroquine®. Further recorded data from their ADMET study, as well as their chemotaxonomy, are also discussed herein. The present study provides further information to enrich the chemistry of Z. gilletii and its qualification as an important source for good candidates in new antiplasmodial drug development.

21 March 2023 in Molecules
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Livie Blondele KENOU MEKUETELivie Blondele KENOU MEKUETE
Livie Blondele KENOU MEKUETE
WTWillifred Dongmo Tékapi Tsopgni
Willifred Dongmo Tékapi Tsopgni
ANAugustine Kuinze Nkojap
Augustine Kuinze Nkojap
JKJacquy Joyce Wanche Kojom
Jacquy Joyce Wanche Kojom
TSTimo Stark
Timo Stark
AAAnatole Guy Blaise Azebaze
Anatole Guy Blaise Azebaze
The phytochemical study of the ethanolic extract of the leaf of Xeroderris stuhlmannii led to the isolation of five hitherto unreported compounds including two isoflavones (1–2), and three rotenoids (3–5), along with eight known isoflavonoid derivatives (6–13) and one pterocarpan derivative (14). The structures of the new compounds and those of the known ones were established by the spectroscopic (1D and 2D NMR) and spectrometric (HRESIMS) techniques as well as a comparison of their spectroscopic data with those reported in the literature. The leaf extract, fractions, and isolated compounds were tested for their antibacterial effects against nine bacterial strains. Compounds 3, 8, 11, and 12 showed a significant antibacterial effect, with a minimum inhibitory concentration (MIC) value of 62.5 µg/mL each, against Salmonella typhi, Staphylococcus aureus, Klessiella pneumonae, and Escherichia coli, respectively. In addition, the leaf extract, fractions, and isolated compounds were tested for their antifungal effects against four fungal strains. The hexane fraction showed a significant antifungal effect with an MIC value of 125 µg/mL against Candida parasilosis, whereas compounds 3, 8, and 12 showed significant antifungal activity with an MIC value of 62.5 µg/mL, each against Candida parasilosis, Candida albicans, and Candida krusei, respectively.

17 January 2022 in Antibiotics
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LNLidwine Ngah
Lidwine Ngah
WTWillifred Dongmo Tékapi Tsopgni
Willifred Dongmo Tékapi Tsopgni
JBJudith Caroline NGO NYOBE NGO NYOBE Epse BIWOLE BENGONDO
Judith Caroline NGO NYOBE NGO NYOBE Epse BIWOLE BENGONDO
ATAlain Tadjong Tcho
Alain Tadjong Tcho
MLMoses Langat
Moses Langat
MPMethee Phumthum
Methee Phumthum
A chemical investigation of the leaves of Tabernaemontana inconspicua Stapf. led to the isolation of a new phenylpropanol derivative, namely irisdichototin G (1), together with nine known compounds, including one polyol derivative, dambonitol (2); three alkaloids, 10-hydroxycoronaridine (3), voacristine (4) and vobasine (5); two triterpenes lupeol (6), betulinic acid (7) and three sterols, sitosterol (8), sitosterol-3-O-β-D-glucopyranoside (9) and stigmasterol (10). The structure of the new compound, as well as those of the known ones, was established by means of spectroscopic methods: NMR analysis (1H and 13C NMR, 1H-1H-COSY, HSQC, HMBC and NOESY), high-resolution mass spectrometry (HR-ESI-MS) and comparisons with previously reported data. Among the known compounds, compound 2 was firstly reported from the family Apocynaceae. Compounds 1–5 were tested for their antimicrobial effects against three Gram-negative organisms associated with human wound and systemic infections, namely Haemophilus influenzae 9435337A, Klebsiella pneumoniae 17102005 and Pseudomonas aeruginosa 2137659B. Compounds 1, 3, and 5 showed significant antimicrobial effects with minimum inhibitory concentrations (MIC) of 62.5 μg/mL, 62.5 μg/mL and 7.81 μg/mL, respectively, against Haemophilus influenzae, whereas compounds 1 and 5 showed significant antimicrobial effects, with a MIC value of 31.25 μg/mL against Pseudomonas aeruginosa. In addition, compound 3 showed significant antimicrobial activity, with a MIC value of 31.25 μg/mL against Klebsiella pneumoniae.

24 December 2023 in Natural Product Research
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LTLaurel Flairon Fotso Tatio
Laurel Flairon Fotso Tatio
ABAchille Nouga Bissoue
Achille Nouga Bissoue
ATAlain Tadjong Tcho
Alain Tadjong Tcho
SASergi Herve Akone
Sergi Herve Akone
NJNadege Nelly Jounda
Nadege Nelly Jounda
AWAlain François Kamdem Waffo
Alain François Kamdem Waffo
The chemical investigation of the methanolic leaf extract of Trichilia dregeana Sond. led to the isolation of a hitherto unreported cycloartane-type triterpene, dregeanol (1), together with nine known compounds, (3 beta,23E)-9,19-cyclolanosta-23,25-dien-3-ol (2), 9,19-cyclolanost-24-en-23-one (3), 6 beta-hydroxystigmasta-4,22-dien-3-one (4), lyoniresinol (5), maslinic acid (6), asperphernamate (7), mixture of stigmasterol (8) and beta-sitosterol (9) and beta-sitosterol-3-O-beta-D-glucopyranoside (10). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. Compounds 2 and 6 showed significant antibacterial effect against Escherichia coli and Salmonella enteritidis, res-pectively, with MIC value of 31.25 mu g/mL, whilst they displayed moderate antifungal effect with MIC value of 62.5 mu g/mL against Candida albicans. All the isolates except compound 3 were found to possess a weak antioxidant potential in the DPPH, ABTS and FRAP assays.

21 September 2022 in Natural Resources for Human Health
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LDLiliane Clotilde Dzouemo
Liliane Clotilde Dzouemo
EHEmmanuel Ngeufa Happi
Emmanuel Ngeufa Happi
GHGervais Mouthé Happi
Gervais Mouthé Happi
WTWillifred Dongmo Tékapi Tsopgni
Willifred Dongmo Tékapi Tsopgni
JWJean Duplex Wansi
Jean Duplex Wansi
The roots of Zanthoxylum gilletii have been chemically investigated and led to the isolation and characterization of nine compounds including three benzo[c]phenanthridine alkaloids oxychelerythrine (1), angoline (2) and arnottianamide (3); two glycosylated flavonoids hesperidin (4) and its analogue neohesperidin (5) along with four common specialized metabolites including sesamin (6), lupeol (7), β-sitosterol (8) and its derivative daucosterol (9). Their structures were established based on their recorded 1D and 2D-NMR data. Some compounds (1, 2, 3, 6 and 7) did not display a cytotoxic activity until the highest concentration of 200 μM against the human cell lines MCF-7 and A549. The chemotaxonomic relevance of this study has been discussed. To the best of our knowledge, except for the five compounds 3, 6-9, all the four others have been for the first time isolated from Z. gilletii (Rutaceae).

21 August 2023 in Natural Product Research
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CTCharlemagne Ndoumbe Tamba
Charlemagne Ndoumbe Tamba
WTWillifred Dongmo Tékapi Tsopgni
Willifred Dongmo Tékapi Tsopgni
BFBernard Samuel Hodjie Fotso
Bernard Samuel Hodjie Fotso
JEJean Pierre Longue Ekon
Jean Pierre Longue Ekon
MNMohamed Foundikou Nsangou
Mohamed Foundikou Nsangou
JNJean Claude Ndom
Jean Claude Ndom
The chemical investigation of the methanolic root extract of Caloncoba glauca (P. Beauv.) Gilg exhibited two new 30-norfriedelane triterpenes, glaucalactones A and B (1-2), together with eight known compounds, caloncobalactone (3), friedelin (4), friedelanol (5), 3-oxo-friedelan-28-oic acid (6), stigmasterol (7), β-sitosterol (8), β-sitosterol-3-O-β-D-glucopyranoside (9) and pentacosanoic acid (10). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. All the compounds were tested for their antioxidant, antifungal and antibacterial activities. Compound 1 displayed weak antibacterial effect with MIC value of 125 μg/mL against Staphylococcus aureus and Escherishia coli. Compound 6 exhibited moderated antifungal activity against Candida krusei with MIC value of 62.5 μg/mL. All the isolates were found to be inactive as antioxidants in the DPPH, ABTS and FRAP assays.