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Nine new eudesmanolides (1-9), two new guaianolides (12and 13), and a new germacrane (10), along with a previously reported guaianolide (11), have been isolated from the roots of Thapsia nitidavar. meridionalis. Thapsia nitida var. nitidaalso afforded compound 13along with a new guaianolide (14). The structure of 13was confirmed by X-ray crystallographic analysis. Compounds 1, 2, and 11-14have been tested as potential inhibitors of the sarco- and endoplasmic Ca2-dependent ATPases (SERCA) pump. None of them showed significant activities.

Three new naphthylisoquinoline alkaloids, the 7,3‘-coupled ancistrotanzanine C (6), the 5,1‘-coupled O-methylancistrocladinine (7), and the likewise 5,1‘-coupled O,N-dimethylancistrocladine (8, previously known only as a partial-synthetic compound), have been isolated from the highland liana Ancistrocladus tanzaniensis, along with the two known 7,3‘-coupled naphthylisoquinoline alkaloids ancistrocladidine (4) and ancistrotectorine (5). All of the compounds are S-configured at C-3 and bear an oxygen at C-6, and thus belong to the so-called Ancistrocladaceae type, similar to 1−3 previously isolated from this newly discovered plant species. The structural elucidation was achieved by chemical, spectroscopic, and chiroptical methods. The biological activities of the alkaloids against the pathogens causing malaria tropica, leishmaniasis, Chagas' disease, and African sleeping sickness were evaluated.

The first phytochemical investigation of the recently discovered East African liana Ancistrocladus tanzaniensis is described, resulting in the isolation and structural elucidation of two new naphthylisoquinoline alkaloids, ancistrotanzanines A (5) and B (6), and the known compound ancistrotectoriline A (7). Ancistrotazanine A (5) represents a hitherto unprecedented 5,3‘-coupling type between the naphthalene and isoquinoline portions, while 6 and 7 are 5,8‘-coupled. The structures of the compounds were determined by spectroscopic, chemical, and chiroptical methods. Compounds 5 and 6 showed good activities against the pathogens of leishmaniasis and Chagas' disease, Leishmania donovani and Trypanosoma cruzi, while 5−7 displayed moderately potent antiplasmodial activities against Plasmodium falciparum parasites.

A bioactivity-guided fractionation of an extract of Terminalia bellerica fruit rind led to the isolation of two new lignans named termilignan (1) and thannilignan (2), together with 7-hydroxy-3‘,4‘-(methylenedioxy)flavan (3) and anolignan B (4). All four compounds possessed demonstrable anti-HIV-1, antimalarial, and antifungal activity in vitro.

As a part of a study on new antiplasmodial natural products, a new 8−5‘ linked lignan dehydrodiconiferyl dibenzoate (2) and p-hydroxybenzoic acid (1) were isolated from the roots of the palm Euterpe precatoria. In contrast to compound 1, compound 2 showed a moderate antiplasmodial activity.

Fractionation of an ethanol extract of roots of Cochlospermum tinctorium afforded five compounds:  3-O-E-p-coumaroylalphitolic acid (1), cochloxanthin (2), dihydrocochloxanthin (3), alphitolic acid (4), and 1-hydroxytetradecan-3-one (5). This is the first example of a 1-hydroxyalkan-3-one obtained from plant material after gentle workup. The antiplasmodial activities of the compounds were determined, and the IC50 value of 3-O-E-p-coumaroylalphitolic acid was 2.3 μM.

Minquartynoic acid (1) was isolated as an antimalarial and antileishmanial constituent of the Peruvian tree Minquartia guianensis and its absolute configuration at C-17 established to be (+)-S through conversion to the known (+)-(S)-17-hydroxystearic acid (2) and confirmed using Mosher's method.