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Six new 14-membered ring cyclopeptide alkaloids, cambodines A–F (1–6), and two known compounds, frangufoline (7) and lotusanine B (8), were isolated from the root bark extract of Ziziphus cambodiana Pierre. Their structures and configurations were established based on 1D and 2D NMR, HRMS, ECD, and X-ray crystallographic data. Compounds 1 and 3 are rare 5(14)-type cyclopeptide alkaloids that possess an imidazolidin-4-one ring in the terminal unit. The cyclopeptides were tested for their in vitro antiplasmodial, antitubercular, and cytotoxic effects against three cancer cell lines. Compound 3 showed significant antiplasmodial activity against the malarial parasite Plasmodium falciparum, with an IC50 value of 6.09 μM.

Sanjoinine A ( 1 ) was synthesized from a 14-membered cyclopeptide prepared from a Garner aldehyde derived from d -serine. The key steps in the synthesis were the catalytic asymmetric reduction of ketone 2(b) and the final removal of the Boc group.

14-Membered cyclopeptide alkaloids, franganine, frangufoline, amphibine-D and mauritine-A has been isolated from the whole plant ot Zizyphus xylopyra and their structures established by spectral evidences. This Is the first report of these alkaloids from Z. xylopyra.