Structure-activity relationship of benzophenanthridine alkaloids from Zanthoxylum rhoifolium having antimicrobial activity.

Zanthoxylum rhoifolium (Rutaceae) is a plant alkaloid that grows in South America and has been used in Brazilian traditional medicine for the treatment of different health problems. The present study was designed to evaluate the antimicrobial activity of the steam bark crude methanol extract, fractions, and pure alkaloids of Z. rhoifolium.

Composition and antibacterial activity of the essential oils from Zanthoxylum rhoifolium.

The essential oils from the aerial parts of leaves, fruits and flowers of Zanthoxylum rhoifolium of Southern Brazil (Rio Grande do Sul), were analysed by GC, GC/MS, and chiral phase gas chromatography (CPGC). Forty-eight compounds were identified from the essential oils. The major constituents of the essential oil of the leaves were germacrene D (34 %) and bicyclogermacrene (23 %) and of the fruits, menth-2-en-1-ol (46.

Antibacterial alkaloids from Zanthoxylum rhoifolium.

Two new dihydrobenzophenanthridine-type alkaloids, 6-methoxy dioxolo[4',5':4,5]benzo[c] dioxolo[4,5- j]phenanthridine (1) and 2,3,13-trimethoxy-5,11a-dihydro dioxolo[4',5':4,5]benzo[c]phenanthridine (2) were isolated from the stem bark of Zanthoxylum rhoifolium, together with four other previously known benzophenanthridine alkaloids, 6-acetonyldihydronitidine (3) [= 8-acetonyldihydronitidine], 6-acetonyldihydroavicine (4) [= 8-acetonyldihydroavicine], 6-acetonyldihydrochelerythrine (5) and xanthoxyline (6). The structures were elucidated mainly by spectroscopic methods, including 1D and 2D NMR spectroscopy. For alkaloids 1 and 2 we propose the trivial names rhoifolines A and B.