| Autor: |
Mbarga PE; Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon., Fouotsa H; Department of Engineering Process, National Higher Polytechnic School of Douala, University of Douala, Douala, Cameroon., Ndemangou B; University Institute of Wood Technology of Mbalmayo, University of Yaoundé I, Yaoundé, Cameroun., Pagna JIM; Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon., Mbekou IMK; Department of Biochemistry, Faculty of Science, The University of Yaoundé I, Yaoundé, Cameroon., Mkounga P; Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon., Stammler HG; Inorganic and Structural Chemistry, Faculty of Chemistry, Bielefeld University, Bielefeld, Germany., Frese M; Department Organic and Bioorganic Chemistry, Faculty of Chemistry, Bielefeld University, Bielefeld, Germany., Boyom Fekam F; Department of Biochemistry, Faculty of Science, The University of Yaoundé I, Yaoundé, Cameroon., Lenta BN; Department of Chemistry, Higher Teacher Training College, University of Yaoundé I, Yaoundé, Cameroon., Sewald N; Department Organic and Bioorganic Chemistry, Faculty of Chemistry, Bielefeld University, Bielefeld, Germany., Nkengfack EA; Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon. |
| Abstrakt: |
The bio guided fractionation of the dichloromethane/methanol (1:1) crude extract of the air-dried whole plant of C. aegyptiaca led to the isolation of one new flavone derivative designated conyflavone ( 1 ) and one new clerodane diterpene type designated conyclerodane ( 2 ) along with five known compounds including two flavonoids Gardenin C ( 3 ), chrysosplenetin ( 4 ) and two steroids glucoside of β -sitosterol ( 5 ), the mixture of stigmasterol ( 6 ) and β -sitosterol ( 6' ) and ent-2b,18,19trihydroxycleroda-3,13-dien-16,15-olide ( 7 ). The structures were established by spectroscopic methods including IR, 1D and 2D NMR in conjunction with mass spectroscopy and by comparison to data of related compounds described in literature. The stereocentres in compound 2 were determined by SC-XRD analysis. Crude extract as well as fractions and pure compounds were evaluated in vitro for their antibacterial activities against four pathogenic and two clinical isolate strains using microdilution methods. Extracts and compounds displayed a moderate antibacterial activity with MIC values ranging from 125 to 500 µg/mL. |
