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Aspidopterys obcordata vine is a Chinese Dai ethnic herb used to treat urolithiasis. However, the material basis and underlying mechanisms remain undefined. In this study, a 2.3 kD inulin-like A. obcordata fructan (AOFOS) was isolated by size exclusion column chromatography and characterized by ultrahigh-performance liquid chromatography-ion trap-time of flight mass spectrometry (UPLC-IT-TOF-MS), nuclear magnetic resonance (NMR) spectroscopy, gas chromatography mass spectrometry (GC-MS) and high-performance gel permeation chromatography (HGPC). In addition, AOFOS showed unique anti-urolithiasis activity in Drosophila kidney stone models. Mechanism study indicated that AOFOS reduced the size of calcium oxalate crystals by inhibiting the formation of large size crystals and the generation rate of calcium oxalate crystals as well as the crystal form conversion from calcium oxalate monohydrate (COM) to calcium oxalate dihydrate (COD).

Trichiliasinenoids A–C (1–3), three new limonoids with an unprecedented C-29-C-7 connecting carbon skeleton formed by migration of C-7 from C-6 to C-29 of a mexicanolide-type limonoid precursor were isolated from the leaves and twigs of Trichilia sinensis. Their structures were assigned by spectroscopic analysis, and the absolute configurations were determined by X-ray crystallography (1) and ECD calculation (2 and 3). A possible biosynthetic pathway of 1 was also proposed. Compound 2 exhibited moderate cytotoxicity against HL-60 cells and weak cytotoxicity against SMMC-7721cells.

Chemical investigation of Lansium domesticum has led to the isolation of two undescribed compounds, namely 17(20)E-dyscusin B (1) and 17(20)Z-dyscusin B (2), as well as three known ones (3 – 5). Structural elucidation was accomplished by the analysis of NMR, MS and IR data. Compounds 1 and 2 were a pair of Δ17(20) geometric isomers of pregnane steroids and showed the significant nitric oxide (NO) inhibitory activities.

The substitutional effect in the selective synthesis of cis, trans stilbenes and 3-arylcoumarins has been described. The regio- and geometrical selectivity for synthesis of stilbene derivatives under the Perkin strategy strongly depends on the presence or absence of hydroxyl group as well as their positions in the phenyl ring. As a result, practical synthetic strategies were established for preparing various natural stilbenes including combretastatin A-4, pterostilbene, and resveratrol with satisfactory yields (49.2–63.7%).

A practical and green protocol for the synthesis of vasculardisrupting agent combretastatin A-4 (CA4) and its water soluble prodrugCA4P is described. Starting from the biomass-based compound anethole,which is abundantly and sustainably available from Chinese staranise ( ILLICIUM VERUM Hook. f.), thekey intermediate 3-hydroxy-4-methoxyphenylacetic acid can be obtainedwithin five steps. Perkin condensation between this acid and anothernaturally derived compound 3,4,5-trimethoxybenzaldehyde, followedby decarboxylation gives combretastatin A-4 in good overall yield.The phosphate produrg CA4P can be prepared under simple and mild conditionsin a sequential one-pot two-step reaction.

The practical synthesis of important natural polyphenolic stilbenes, including resveratrol, piceatannol and oxyresveratrol, through Perkin methodology is described. Starting from 3,5-dihydoxyacetophenone (1), the common intermediate 3,5-dimethoxyphenylacetic acid (3) can be obtained via methylation and Willgerodt-Kindler reaction. Perkin condensations between (3) and substituted phenylaldehydes 4 furnished E-2,3-diarylacrylic acids 5, followed by decarboxylation in Cu/quinoline giving stilbene intermediates 6 which bear the Z-configuration. Finally, through a simultaneous demethylation/isomerization process in AlI₃/CH₃CN system, the target compounds 7a-c can be obtained respectively in good to high overall yields. The synthetic method proved to be more concise, trans-specific, mild, economical and commonly applicable.

A concise route to two anti-tubulin natural products combretastatin A-4 and erianin has been developed. Combretastatin A-4 was obtained by a Perkin reaction between 3-bromo-4-methoxyphenyl acetic acid and 3,4,5-trimethoxybenzaldehyde, hydroxyl transformation, decarboxylation with a high level of cis-selectivity ( cis/trans = 95/5), and erianin was obtained by subsequent hydrogenation. The overall yields of combretastatin A-4 and erianin were 37.5 and 30.8%, respectively.

The Perkin condensation of acid (IV) with aldehyde (V) followed by a copper-promoted decarboxylation and subsequent demethylation-isomerization reaction gives rise to resveratrol (VIIIa).