Synthesis of a novel diarylheptanoid isolated from Zingiber officinale

Recent Advances in the Synthesis of Diarylheptanoids

In the quest for synthesizing biologically important natural products, medicinal chemists embark on an endless journey. This review focuses on the reports published towards the syntheses of diarylheptanoids, classifying them into linear, tetrahydropyran, diarylether, and biphenyl categories. The synthesis methods for each class from 2013 to 2023 are discussed, providing a comprehensive overview of the advancements in the field. Representative natural product examples are highlighted for each category. The review emphasizes the importance of diarylheptanoids in the realms of chemistry and medicine, showcasing their potential as valuable compounds for medicinal and synthetic chemists.

Diarylheptanoid glycosides from Zingiber officinale peel and their anti-apoptotic activity

Four new diarylheptanoid glycosides (1-4), (1S,3R,5S)-2-(4-hydroxy-3- methoxyphenyl)-6-[2-(4-hydroxyphenyl)ethyl]-tetrahydropyran-4-ol-4'-O-β-D-glucopyranoside (1), (1S,3R,5S)-2-(4,5-dihydroxy-3-methoxyphenyl)-6-[2-(4-hydroxyphenyl) ethyl]-tetrahydropyran-4-ol-4'-O-β-D-glucopyranoside (2), (1S,3R,5S)-2-(4-hydroxy- 3,5-dimethoxyphenyl)-6-[2-(4-hydroxy-3-methoxyphenyl)ethyl]-tetrahydropyran-4-ol-4'-O-β-D-glucopyranoside (3), and (1R,3R,5R)-2-(4-hydroxy-3,5-dimethoxyphenyl)- 6-[2-(4-hydroxy-3-methoxyphenyl)ethyl]-tetrahydropyran-4-ol-3-O-β-D-glucopyranoside (4) were isolated from the 50% ethanol extract of Zingiber officinale peel. The structures of the isolated compounds were determined by HR-ESI-MS and extensive spectroscopic techniques (UV, IR, 1D-NMR, and 2D-NMR). Compounds 1-4 significantly increased the survival rate of human normal lung bronchial epithelial cells (BEAS-2B) induced by lipopolysaccharide (LPS) at the concentration of 10 μM.

Diarylheptanoids from Rhizomes of Alpinia officinarum Inhibit Aggregation of α-Synuclein

Two new diarylheptanoids, alpinin A (1) and alpinin B (2), together with 18 known diarylheptanoids (3-20), were isolated from the rhizomes of Alpinia officinarum. Their structures were elucidated by comprehensive spectroscopic analysis, including high-resolution mass spectrometry, infrared spectroscopy, and one- and two-dimensional nuclear magnetic resonance spectroscopy. Structurally, alpinin A is a new member of the small family of oxa-bridged diarylheptanoids and contains the characteristic 2,6-cis-configured tetrahydropyran motif (C₁-C₅ oxa bridge). The absolute configuration of alpinin A was confirmed by asymmetric total synthesis of the enantiomer (ent-1), corroborating the assignment of the molecular structure. The absolute configuration of alpinin B was determined on the basis of the analysis of the circular dichroism exciton chirality spectrum. We evaluated the inhibitory activity of all isolated diarylheptanoids against α-synuclein aggregation at 10 μM. Alpinins A and B significantly inhibited α-synuclein aggregation by 66 and 67%, respectively.

A natural product inspired tetrahydropyran collection yields mitosis modulators that synergistically target CSE1L and tubulin

A Prins cyclization between a polymer-bound aldehyde and a homoallylic alcohol served as the key step in the synthesis of tetrahydropyran derivatives. A phenotypic screen led to the identification of compounds that inhibit mitosis (as seen by the accumulation of round cells with condensed DNA and membrane blebs). These compounds were termed tubulexins as they target the CSE1L protein and the vinca alkaloid binding site of tubulin.