Strychnogucines a and B, Two New Antiplasmodial Bisindole Alkaloids from Strychnos Icaja

in Journal of Natural Products (2001), 64(1), 12-16

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by ... [more ▼]

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by means of spectroscopic data interpretation. Compound 2 was highly active in vitro and compound 1 moderately active against four strains of Plasmodium falciparum. Strychnogucine B (2) was more active against a chloroquine-resistant strain than against a chloroquine-sensitive one (best CI(50), 80 nM against the W2 strain). In addition, this compound showed a selective antiplasmodial activity with 25-180 times greater toxicity toward P. falciparum, relative to cultured human cancer cells (KB) or human fibroblasts (WI38). [less ▲]

Etude du mécanisme d’action d’alcaloides bisindoliques, isolés du Strychnos icaja, à potentialité anticancéreuse

Poster (2000, July)

New Antimalarial and Cytotoxic Sungucine Derivatives from Strychnos Icaja Roots

in Planta Medica (2000), 66(3), 262-9

Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy ... [more ▼]

Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy-isosungucine (10). They were identified by detailed spectroscopic methods. The complete 1H- and 13C-NMR study of sungucine was also realized. Some of these compounds were highly active against Plasmodium falciparum in vitro and more particularly against the chloroquine-resistant strain. Compound 10 showed a selective antiplasmodial activity, with > 100-fold greater toxicity towards Plasmodium falciparum, relative to cultured human cancer cells (KB and HeLa lines) or fibroblasts (WI38). [less ▲]

Anti-inflammatory and chondroprotective activity of prodelphinidins isolated from Ribes nigrum leaves.

Poster (2000)

Guiaflavine, a New Bisindole Quaternary Alkaloid from the Stem Bark of Strychnos Guianensis

in Journal of Natural Products (1999), 62(6), 898-900

A reinvestigation of Strychnos guianensis resulted in the isolation of a colored quaternary bisindole alkaloid from the stem bark. The structure of this new substance, guiaflavine (1), was defined by ... [more ▼]

A reinvestigation of Strychnos guianensis resulted in the isolation of a colored quaternary bisindole alkaloid from the stem bark. The structure of this new substance, guiaflavine (1), was defined by detailed spectroscopic methods and comparison with model compounds. [less ▲]

In vitro activity of african Strychnos alkaloids against chloroquine resistant plasmodium falciparum

Poster (1999)

The plant alkaloid usambarensine intercalates into DNA and induces apoptosis in human HL60 leukemia cells

in Anticancer Research (1999), 19(6B), 5245-5250

Strychnochrysine, a New Bisindole Alkaloid from the Roots of Strychnos Nux-Vomica

in Journal of Natural Products (1998), 61(1), 139-41

The reinvestigation of Strychnos nux-vomica resulted in the isolation of a colored monoquaternary bisindole alkaloid from the roots. The structure of this new orange substance, strychnochrysine (1), was ... [more ▼]

The reinvestigation of Strychnos nux-vomica resulted in the isolation of a colored monoquaternary bisindole alkaloid from the roots. The structure of this new orange substance, strychnochrysine (1), was defined by detailed spectroscopic methods. [less ▲]

Qualitative and quantitative evaluation of bisindole usambarane alkaloids in Strychnos usambarensis roots by high performance liquid chromatography diode-array

in Phytochemical Analysis [=PCA] (1998), 9(2), 63-66

A high performance liquid chromatographic method for the simultaneous determination of bisindole usambarane alkaloids from the roots of Strychnos usambarensis using a diode-array detector is proposed, The ... [more ▼]

A high performance liquid chromatographic method for the simultaneous determination of bisindole usambarane alkaloids from the roots of Strychnos usambarensis using a diode-array detector is proposed, The system, consisting of a RP-8 Select B column and a linear gradient elution with acetonitrile and acetate buffer allowed the separation of all the alkaloids in 20 min, Usambarensine was found to be the major tertiary alkaloid present in the roots, In order to demonstrate the possibility of quantifying the bisindole alkaloids in crude roots extracts, the quantitative evaluation of 3',4'-dihydrousambarensine, usambarensine and N-b-methylusambarensine was carried out. (C) 1998 John Wiley & Sons, Ltd. [less ▲]