An antileishmanial prenyloxy-naphthoquinone from roots of Plumbago zeylanica.

Leishmania donovani, an obligate intracellular parasite of genus Leishmania causes visceral leishmaniasis that affects millions of people worldwide, especially in the Indian subcontinent and East Africa. Generic pentavalent antimonials have been the mainstay for therapy in the endemic regions due to efficacy and cost effectiveness but the growing incidence of their resistance has seriously hampered their use. This study discloses strong in vitro antileishmanial activity of 2-methyl-5 -(3'-methyl-but-2'-enyloxy)-[1,4]naphthoquinone (1), a prenyloxy-naphthoquinone isolated and characterised from roots of the plant Plumbago zeylanica (family-Plumbaginaceae). The observed EC50 for the compound 1 against promastigote and amastigote forms of L. donovani was significantly (p<0.001) lower than miltefosine, a reference drug. In context to limited treatment options and growing resistance for available drugs, compound 1 offers a greater prospect towards antileishmanial drug discovery and development.

Antifungal constituents isolated from the seeds of Aegle marmelos.

Antifungal constituents, 2-isopropenyl-4-methyl-1-oxa-cyclopenta[b]anthracene-5,10-dione and (+)-4-(2'-hydroxy-3'-methylbut-3'-enyloxy)-8H-[1,3]dioxolo[4,5-h]chromen-8-one in addition to known compounds imperatorin, beta-sitosterol, plumbagin, 1-methyl-2-(3'-methyl-but-2'-enyloxy)-anthraquinone, beta-sitosterol glucoside, stigmasterol, vanillin and salicin were isolated during phytochemical investigation on seeds of Aegle marmelos Correa.

A novel antifungal anthraquinone from seeds of Aegle marmelos Correa (family Rutaceae).

A new anthraquinone, 1-methyl-2-(3'-methyl-but-2'-enyloxy)-anthraquinone (1) has been isolated from seeds of Aegle marmelos Correa and was characterized on the basis of spectral analysis (UV, IR, 1H NMR, 13C NMR, 2D NMR and mass spectroscopy). The compound exhibited significant antifungal activity against pathogenic strains of Aspergillus species and Candida albicans in disc diffusion assay (MIC value of 6.25 microg/disc), microbroth dilution and percent spore germination inhibition assays (MIC value of 31.25-62.5 microg/ml).

Alkaloids as potential anti-tubercular agents.

An increasing incidence of deaths due to tuberculosis and the known drawbacks of the current existing drugs including the emergence of multi drug-resistant strains have led to a renewed interest in the discovery of new anti-tubercular agents with novel modes of actions. The recent researches focused on natural products have shown a useful way to obtain a potentially rich source of drug candidates, where alkaloids have been found more effective. The present review focuses on current epidemiology of tuberculosis, synergy of the disease with HIV, current therapy, available molecular targets and, highlights why natural products especially alkaloids are so important. The review summarizes alkaloids found active against mycobacteria from the mid-1980s to late 2008 with special attention on the study of structure-activity relationship (SAR).

A novel flavonoid C-glycoside from Sphaeranthus indicus L. (family Compositae).

A novel flavonoid C-glycoside, 5-hydroxy-7-methoxy-6-C-glycosylflavone (1), was isolated from the aerial part of Sphaeranthus indicus. Its structure was elucidated by spectroscopic methods.

A new triterpenoid from Lantana camara.

A new ursane was isolated from the leaves of Lantana camara and its structure elucidated as 3,24-dioxo-urs-12-en-28-oic acid (1) by means of spectral analysis.