Two new pterocarpans and a new pyrone derivative with cytotoxic activities fromPtycholobium contortum(N.E.Br.) Brummitt (Leguminosae): revised NMR assignment of mundulea lactone.
BACKGROUND
Ptycholobiumis a genus related toTephrosiawhich comprises only three species. Compared toTephrosia, which has been phytochemically and pharmacologically studied,Ptycholobiumspecies have only few or no reports on their chemical constituents. Moreover, no studies on the cytotoxic activities of its secondary metabolites have been previously documented.


RESULTS
From the non polar fractions of the roots bark ofPtycholobium contortum(synTephrosia contorta), two new pterocarpans: seputhecarpan C1and seputhecarpan D2and a new pyrone derivative, ptycholopyrone A3were isolated. Alongside, five known compounds identified as 3-α,α-dimethylallyl-4-methoxy-6-styryl-α-pyrone or mundulea lactone4, glyasperin F5, seputhecarpan A6, seputheisoflavone7and 5-O-methyl-myo-inositol or sequoyitol8were also obtained. Their structures were established by the mean means of spectroscopic data in conjunction to those reported in literature. The NMR assignment of the major compound mundulea lactone4is revised in this paper. In addition, the cytotoxicity of the isolated metabolites was evaluated on two lung cancer cell lines A549 and SPC212.8was not active while compounds1, 2, 4-7displayed antiproliferative effects against the two carcinoma cell lines with IC50values below 75 µM. IC50values below 10 µM were obtained for4, 6and7on SPC212 cells.


CONCLUSIONS
Based on the obtained results,Ptycholobium contortumturns to be a rich source of phenolic metabolites among them some bearing prenyl moieties. This study reports for the first time the isolation of pyrone derivatives3and4fromPtycholobiumgenus. The cytotoxicity observed for the isolate is also reported for the first time and shows that4, 6and7could be chemically explored in order to develop a hit candidate against lung cancer. Graphical abstractTwo new pterocarpans and a new pyrone derivative with cytotoxic activities from ptycholobium contortum (N.E.Br.) Brummitt (Leguminosae): revised NMR assignment of mundulea lactone.
Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon.
Dominique
D
Ngnintedo
Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon.
Ghislain W
GW
Fotso
Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon ; Department of Biology, Science Faculty, Anadolu University, Eskişehir, Turkey.
Victor
V
Kuete
Molecular Engineering Laboratory and Formerly Pharmacological Biochemistry, UMR-SRSMC 7565, University of Lorraine, 1 Boulevard Arago, Metz Technopole, 57070 Nancy, France.
Frederic
F
Nana
Department of Pharmaceutical Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, Florianópolis, SC 88040-900 Brazil.
Louis P
LP
Sandjo
Department of Biology, Science Faculty, Anadolu University, Eskişehir, Turkey ; Department of Biology, Kamil Özdağ Science Faculty, Karamanoğlu Mehmetbey University, Karaman, Turkey.
Oğuzhan
O
Karaosmanoğlu
Department of Biology, Science Faculty, Anadolu University, Eskişehir, Turkey.
Hülya
H
Sivas
Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon.
Felix
F
Keumedjio
Molecular Engineering Laboratory and Formerly Pharmacological Biochemistry, UMR-SRSMC 7565, University of Lorraine, 1 Boulevard Arago, Metz Technopole, 57070 Nancy, France.
Gilbert
G
Kirsch
Department of Organic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon ; Department of Pharmacognosy and Pharmaceutical Sciences, Faculty of Medicine and Biomedical Science, University of Yaoundé I, Yaoundé, Cameroon.
Bonaventure T
BT
Ngadjui
Department of Biological Sciences, Faculty of Science, University of Botswana, Block 235, Private Bag, 0022 Gaborone, Botswana.
Kerstin
K
Andrae-Marobela
Cytotoxic activities; Ptycholobium contortum; Ptycholopyrone A; Seputhecarpan C; Seputhecarpan D