Lysosomal phospholipases inhibition by emetine, strychnopentamine and usambarensine

Poster (1999)

Cryptolepine is a potent DNA intercalating agent which inhibits selectively DNA synthesis in B16 melanoma cells cultured in vitro

Poster (1997)

Purification and analysis by mass spectometry of low M.W. soluble factors released into conditioned culture media by B16 melanoma cells

Poster (1995, July)

Guianensine, a zwitterionic alkaloid from Strychnos guianensis

in Phytochemistry (1995), 40(5), 1557-1560

The isolation and structure determination of an alkaloid isolated from the stem bark of Strychnos guianensis is described. Elucidation of its structure is based mainly on 1D and 2D NMR studies. The new ... [more ▼]

The isolation and structure determination of an alkaloid isolated from the stem bark of Strychnos guianensis is described. Elucidation of its structure is based mainly on 1D and 2D NMR studies. The new alkaloid has a zwitterionic asymmetrical bis-indole structure and is named guianensine. [less ▲]

2,7-dihydroxyapogeissoschizine from root bark of Strychnos gossweileri

in Phytochemistry (1994), 35(2), 533-536

In this paper, we describe the isolation and structural determination of 2,7-dihydroxyapogeissoschizine, a new alkaloid from the root bark of Strychnos gossweileri. Elucidation of its structure is based ... [more ▼]

In this paper, we describe the isolation and structural determination of 2,7-dihydroxyapogeissoschizine, a new alkaloid from the root bark of Strychnos gossweileri. Elucidation of its structure is based mainly on 1D and 2D NMR studies; its conformation was optimized by energy minimization. This type of skeleton is related to geissoschizine but with the notable diffrence that the 1 and 17 positions are joined giving an additional fused ring. Such a seven-membered ring has ,to our knowledge, only been observed in apogeissoschizine, obtained after chemical tratment of two alkaloids ( geissospermine and geissoschizine). 2,7-dihydroxyapogeissoschizine is therefore, the first natural product possessing this skeleton. According to a preliminary test, this new alkaloid shows low toxicity to B16 melanoma cells, but not for non-cancer 3T3 fibroblasts cultured in vitro.THese results have to be confirmed by further tests. [less ▲]

Antiparasitic Properties of Diploceline, a Quaternary Alkaloid from Strychnos gossweileri

in Planta Medica (1992), 58

The activity of diploceline is relatively weak as compared to metronidazole on Entamoeba histolytica and Trichomonas vaginalis. The quaternary alkaloid does not produce any inhibition of Plasmodium ... [more ▼]

The activity of diploceline is relatively weak as compared to metronidazole on Entamoeba histolytica and Trichomonas vaginalis. The quaternary alkaloid does not produce any inhibition of Plasmodium falciparum growth at 25 micrograms/ml (maximum tested concentration). [less ▲]

Matadine, a cytotoxic alkaloid from Strychnos gossweileri

in Phytochemistry (1991), 30(5), 1697-1700

Matadine, a new alkaloid, has been isolated from the root bark of Strychnos gossweileri. Elucidation of its structure is mainly based on 1H and 1D NMR studies. Its cytotoxic activity has been tested on ... [more ▼]

Matadine, a new alkaloid, has been isolated from the root bark of Strychnos gossweileri. Elucidation of its structure is mainly based on 1H and 1D NMR studies. Its cytotoxic activity has been tested on cancer cells and normal cells. Matadine is an anhydronium base as serpentine, that exerts also a selective inhibiting activity on B16 melanoma cells while it is less toxic in human 2002 non-cancer cells. This selective activity might be well due , as it seems to be the case for serpentine and alstonine, to a higher affinity of matadine for destabilized single-stranded DNA as mainly present in cancer cells. [less ▲]

From ethnobotanical uses of Strychnos henningsii to antiinflammatories, analgesics and antispasmodics

in Journal of Ethnopharmacology (1991), 34

Strychnos henningsii GILG is used in African traditional medicine for the treatment of various ailments, including rheumatism, gastrointestinal complaints, malaria and snake bites. Different preliminary ... [more ▼]

Strychnos henningsii GILG is used in African traditional medicine for the treatment of various ailments, including rheumatism, gastrointestinal complaints, malaria and snake bites. Different preliminary pharmacological experiments are described. The results show that some of the reported folk medicinal applications of S. henningsii can be at least partially explained by the presence of retuline-like alkaloids, whose use could lead to new antinociceptive (antiinflammatory and analgesic) and antispasmodic drugs. [less ▲]

Toxic and mitogenic activities of culture media conditioned by B16 melanoma cells

Conference (1990)

Venecurine, an Indole Alkaloid from Curare

in Phytochemistry (1989), 28(9), 2221-2223

A new quaternary indole alkaloid, venecurine, has been isolated by chromatographic techniques from a curare obtained from the Hoti tribe of Venezuela. Elucidation of its structure is based mainly on 2D ... [more ▼]

A new quaternary indole alkaloid, venecurine, has been isolated by chromatographic techniques from a curare obtained from the Hoti tribe of Venezuela. Elucidation of its structure is based mainly on 2D-NMR studies. Concurrently with the structural work, frog bioassays were carried out. The curare and venecurine exhibit the same type of activity that is relatively low as compared with the dimeric curarizing alkaloids.These results may be an indication that the sample of curare investigated was a weak one intended to be used for capturing rather than killing animals. [less ▲]