10‘-Hydroxyusambarensine, a New Antimalarial Bisindole Alkaloid from the Roots of Strychnos usambarensis

Abstract

Reinvestigation of Strychnos usambarensis Gilg resulted in the isolation of a tertiary phenolic bisindole alkaloid, 10'-hydroxyusambarensine (1), which was identified by detailed spectroscopic methods. Compound 1 was moderately active against two strains of Plasmodium falciparum in vitro.

In vitro antiplasmodial activity and toxicity assessment of plant extracts used in traditional malaria therapy in the Lake Victoria Region

“…The reports on these medicinal plants indicate that the plant species contain antiplasmodial metabolites. The antiplasmodial alkaloids isostrychnofoline (IC 50 1.2 µM) and holstiine (IC 50 1.0 µM) have been isolated from the RB of S. henningnsii Strychnaceae (Frederich et al 1999(Frederich et al , 2002. Most plants from the Celastraceae family contain a class of sesquiterpene nicotinoyl alkaloids, which are characterised by a dihydroagarofuran sesquiterpene bonded as a diester to a substituted nicotinic acid (Schaneberg et al 2001).…”

The potential of anti-malarial compounds derived from African medicinal plants. Part I: A pharmacological evaluation of alkaloids and terpenoids

“…Frédérich et al examined the roots and leaves of Strychnos usambarensis (Loganiaceae) growing in Rwanda [55,56]. Four potent anti-malarial bisindole alkaloids; 10′-hydroxyusambarensine ( 16 ), strychnopentamine ( 17 ), isostrychnopentamine ( 18 ) and chrysopentamine ( 19 ) have been isolated.…”

Chemical Constituents from Strychnos Cathayensis

“…Strychni Se men from S. nux-vomica was a fa mous crude drug that acted as a CNS stim u lant and was also used as a pes ti cide. The lit er a ture has re ported many com po nents, such as indole al ka loids, monoterpene al ka loids, iridoids, flavonoids and ste roids from Strychnos spe cies, [3][4][5] but phytochemical ex am i na tion of S. cathayensis has not yet been con ducted. In ves ti ga tion of the stem of S. cathayensis has led to the iso la tion of one new com pound, a secoiridoid, secostrychnosin ( 1), seven com pounds, 4-tert-butyl-2oxazolidinone (2), 3-acetoxyindole (3), indole-2-carboxylic acid (4), benzocaine (5), 3-acetylindole (6), butylparaben (7) and 2-hydroxy-3-methoxybenzaldehyde (8), which were isolated for the first time from na ture and 50 known com pounds from the stem of S. cathayensis .…”