Gluco-indole alkaloids from the bark of Nauclea diderrichii. 1H and 13C NMR assignments of 3alpha-5alpha-tetrahydrodeoxycordifoline lactam and cadambine acid.

Detailed (1)H and (13)C NMR assignments of 3alpha-5alpha-tetrahydrodeoxycordifoline lactam and cadambine acid, isolated from the bark of the Nauclea diderrichii (de Wild.) Merr. (Rubiaceae) were achieved by 1D and 2D techniques such as DEPT, HMBC, HMQC, COSY and NOESY.

Ethnobotanical survey and in vitro antiplasmodial activity of plants used in traditional medicine in Burkina Faso.

In Burkina Faso, most people in particular, in rural areas, use traditional medicine and medicinal plants to treat usual diseases. In the course of new antimalarial compounds, an ethnobotanical survey has been conducted in different regions. Seven plants, often cited by traditional practitioners and not chemically investigated, have been selected for an antiplasmodial screening: Pavetta crassipes (K. Schum), Acanthospermum hispidum (DC), Terminalia macroptera (Guill. et Perr), Cassia siamea (Lam), Ficus sycomorus (L), Fadogia agrestis (Schweinf. Ex Hiern) and Crossopteryx febrifuga (AFZ. Ex G. Don) Benth. Basic, chloroform, methanol, water-methanol and aqueous crude extracts have been prepared and tested on Plasmodium falciparum chloroquine-resistant W2 strain. A significant activity has been observed with alkaloid extract of P. crassipes (IC(50)<4 microg/ml), of A. hispidum, C. febrifuga, and F. agrestis (4

Antiplasmodial activity of alkaloid extracts from Pavetta crassipes (K. Schum) and Acanthospermum hispidum (DC), two plants used in traditional medicine in Burkina Faso.

In the course of the search for new antimalarial compounds, a study of plants traditionally used against malaria in Burkina Faso was made. An ethnobotanical study permitted the identification of plants currently used by the traditional healers and herbalists. Two plants among them were selected for further study: Pavetta crassipes (K. Schum) and Acanthospermum hispidum (DC). Alkaloid extracts of these plants were tested in vitro against two reference clones of Plasmodium falciparum: the W2 chloroquine-resistant and the D6 chloroquine-sensitive strains. Significant inhibitory activity was observed with Pavetta crassipes (IC(50)=1.23 microg/ml) and A. hispidum (IC(50)=5.02 microg/ml). Antiplasmodial activity was also evaluated against six Plasmodium falciparum isolates from children between 4 and 10 years old. The IC(50) values for the alkaloid extracts were in the range 25-670 ng/ml. These results indicated that P. falciparum wild strains were more sensitive to the alkaloid extracts than strains maintained in continuous culture. Moreover, the alkaloid extracts exhibit good in vitro antimalarial activity and weak cytotoxicity against three human cell lines (THP1, normal melanocytes, HTB-66). Isolation and structural determination are now necessary in order to precisely determine the active compounds.

Antimalarial activity of extracts and alkaloids isolated from six plants used in traditional medicine in Mali and Sao Tome.

Methanol and chloroform extracts were prepared from various parts of four plants collected in Mali: Guiera senegalensis (Gmel.) Combretaceae, Feretia apodanthera (Del.) Rubiaceae, Combretum micranthum (Don.) Combretaceae, Securidaca longepedunculata (Fres.) Polygalaceae and two plants -collected in Sao Tome: Pycnanthus angolensis (Welw.) Myristicaceae and Morinda citrifolia (Benth.) Rubiaceae were assessed for their in vitro antimalarial activity and their cytotoxic effects on human monocytes (THP1 cells) by flow cytometry. The methanol extract of leaves of Feretia apodanthera and the chloroform extract of roots of Guiera senegalensis exhibited a pronounced antimalarial activity. Two alkaloids isolated from the active extract of Guiera senegalensis, harman and tetrahydroharman, showed antimalarial activity (IC(50) lower than 4 microg/mL) and displayed low toxicity against THP1. Moreover, the decrease of THP1 cells in S phase of the cell cycle, after treatment with harman and tetrahydroharman, was probably due to an inhibition of total protein synthesis.

Bisbenzylisoquinoline alkaloids from Guatteria boliviana (Annonaceae).

Together with known alkaloids, five new bisbenzylisoquinoline derivatives were isolated from the stem bark of Guatteria boliviana (Annonaceae), puertogalines-A 1 and -B 2, (+)-guatteboline 3, philogaline 4 and (-)-antioquine 5. Their structures were elucidated by spectrometric methods and their antiparasitic activity was evaluated in vitro on Leishmania sp., Trypanosoma cruzi and Plasmodium falciparum. Their cytotoxic activity was also measured in KB cell line.

New prenylated quinones from Peperomia galioides.

Two new prenylated quinones, piperogalone (1) and galopiperone (2), and a new prenylated dihydroquinone, hydropiperone (3), were isolated from Peperomia galioides H.B.K (Piperaceae). Hydropiperone exhibited potent antiparasitic activity against three species of Leishmania.

In vitro and in vivo leishmanicidal studies of Peperomia galioides (Piperaceae).

Petroleum ether and methylene chloride extracts of Peperomia galioides and three prenylated diphenols, grifolic acid, grifolin and piperogalin exhibited in vitro antileishmanial activity. During the course of infection of BALB/c mice with Leishmania amazonensis, the treatments with each of these compounds did not influence the progression of the disease.

Piperogalin, a new prenylated diphenol from Peperomia galioides.

A petroleum ether extract of Peperomia galoides showed significant in vitro activity against three Leishmania species and Trypanosoma cruzi. Three major prenylated diphenols, including two known compounds, grifolic acid [1], and grifolin [2], and the new substance piperogalin [3], have been isolated. Structures were established on the basis of spectral analysis including 2D nmr spectroscopy.

New aporphine alkaloids from guatteria foliosa.

Four new alkaloids were obtained from Guatteria foliosa, namely, the noraporphines (-)-3-methoxyputerine [1] and (+)-norguattevaline [2], the more highly oxidized (+)-3-methoxyguattescidine [3], and the oxoaporphine 3-methoxyoxoputerine [4]. Among several other known alkaloids also found in this same plant, (-)-3-hydroxynornuciferine, (-)-isoguattouregidine, and argentinine exhibited significant activity against Trypanosoma cruzi.