α‐Hydroxy acids (AHAs) such as lactic acid are considered platform molecules in the biorefinery concept and have high‐end applications in solvents and biodegradable polyester plastics. The synthesis of AHAs with a four‐carbon backbone structure is a recently emerging field. New biomass‐related routes towards their production could stimulate their practical use in new polyester plastics. Herein, we report the unique catalytic activity of soluble tin metal salts for converting tetroses, namely erythrulose and erythrose, into new four‐carbon‐backbone AHAs such as methyl vinylglycolate and methyl‐4‐methoxy‐2‐hydroxybutanoate. An in situ NMR study together with deuterium labeling experiments and control experiments with intermediates allowed us to propose a detailed reaction pathway.

The essential oil from the leaves and stems of Tetradenia riparia was analysed by GC and GC/MS and 35 components were identified. The main constituents were alpha-terpineol (22.6%), fenchone (13.6%), beta-fenchyl alcohol (10.7%), beta-caryophyllene (7.9%), and perillyl alcohol (6.0%). Moderate antimalarial activities were recorded against two strains of Plasmodium falciparum.

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Four known alkaloids, lycorine (1), 1,2-di-O-acetyllycorine (2), ambelline (3), and crinine (4) were isolated from the bulbs of Brunsvigia littoralis (Amaryllidaceae). 1H- and 13C-NMR spectra of 2 were completely assigned by means of 1D- and 2D-NMR techniques. The alkaloids (1-4) together with the synthesised 11-O-acetylambelline (3a) and 3-O-acetylcrinine (4a) were tested for antimalarial activity with two strains of cultured Plasmodium falciparum and for cytotoxicity with BL6 mouse melanoma cells. Structures 1 and 2 exhibited both antimalarial and cytotoxic activity.