Phenolic glycosides from the leaves of Alangium platanifolium var. platanifolium

Phenolic constituents from the branches of Viburnum chinshanense as potential α-amylase and α-glucosidase inhibitory agents

This paper reports the isolation of two undescribed phenolic glycosides (1 and 2), together with seven known compounds (3-9) from the branches of Viburnum chinshanense. The structures of undescribed compounds were elucidated by comprehensive spectroscopic methods (1D NMR, 2D NMR, and HRESIMS). The sugar units of compounds 1 and 2 were identified by acid hydrolysis and HPLC analysis of the chiral derivatives of the monosaccharides. Furthermore, the α‑amylase and α-glucosidase inhibitory activities of all isolates were evaluated and compounds 1, 5, and 8 displayed potential α‑amylase and α-glucosidase inhibitory activities. The molecular docking analyses of compounds 1 and 8 with the potent inhibition towards the target enzymes were also performed.

Genus Alangium - A review on its traditional uses, phytochemistry and pharmacological activities

The species from Alangium have been used as folk medicine to treat rheumatism, skin diseases, diabetes by the people of Southeast Asia. Previous phytochemical studies have shown this genus are rich sources of alkaloids, glycosides, and terpenoids, which have attracted considerable attention of many researchers due to their markedly diverse and complex architecture. The crude extracts as well as the monomeric compounds from the title genus possess anti-tumor, anti-inflammatory, antibacterial, anti-oxidant pharmacological activities. Besides, some isolates from Alangium exhibited the effects on skeletal, smooth muscle and the nervous system. As a large genus of medicinal plants, the medicinal value of Alangium has been widely reported, but there is no review that provide a systematic summary towards its chemical constituents and pharmacological activities, to our knowledge. This work aims to present a comprehensive overview on the traditional uses, phytochemistry, and pharmacological activities of medicinal plants in the genus Alangium, and to explore the evidence supporting its ethnopharmacological effectiveness.

Sesquiterpene glycosides from the roots of Codonopsis pilosula

Three new sesquiterpene glycosides, named codonopsesquilosides A−C (1−3), were isolated from an aqueous extract of the dried roots of Codonopsis pilosula. Their structures including absolute configurations were determined by spectroscopic and chemical methods. These glycosides are categorized as C₁₅ carotenoid (1), gymnomitrane (2), and eudesmane (3) types of sesquiterpenoids, respectively. Compound 1 is the first diglycoside of C₁₅ carotenoids to be reported. Compound 2 represents the second reported example of gymnomitrane-type sesquiterpenoids from higher plants. The absolute configurations were supported by comparison of the experimental circular dichroism (CD) spectra with the calculated electronic CD (ECD) spectra of 1−3, their aglycones, and model compounds based on quantum-mechanical time-dependent density functional theory. The influences of the glycosyls on the calculated ECD spectra of the glycosidic sesquiterpenoids, as well as some nomenclature and descriptive problems with gymnomitrane-type sesquiterpenoids are discussed.

Overview of Taiwan's indigenous ethnopharmacology in the perspective of traditional knowledge protection

Ethnopharmacology, the study of ethnic use of drugs, opens up the crucial gateway to understanding and promoting traditional medicine in the new age. Taiwan is a unique region where traditional medicine and herbal therapeutics have been benefiting its people of multiple races for centuries. This article overviews Taiwan's indigenous traditional medicine and the emerging status of ethnopharmacology study, and outlines the global scenario of the inheritance and development of traditional medicine. In such a scope of knowledge protection, this article particularly highlights the challenges with bioprospecting and biopiracy, and summarizes the current measures for protection of traditional knowledge in Taiwan. Finally, based upon these analyses, we propose rational strategies for promoting Taiwan's ethnopharmacology, from multiple angles of resource, economy, policy and law. We conclude that four measures, namely (1) protecting the natural environment of biodiversity, (2) avoiding unnecessary conflicts caused by bioprospecting and biopiracy, (3) strengthening the international collaboration, and (4) upgrading the legal system of traditional intelligence, would be the right paths for Taiwan to protect its invaluable heritage of traditional medicine and the knowledge of ethnopharmacology therein.

Enzymatic synthesis of two salicin analogues by reaction of salicyl alcohol with Bacillus macerans cyclomaltodextrin glucanyltransferase and Leuconostoc mesenteroides B-742CB dextransucrase

Beta-Salicin is a naturally occurring glycoside found in the bark of poplar and willow trees. Ancient man used it as an analgesic and antipyretic. It has a D-glucopyranose unit attached by a beta-linkage to the phenolic hydroxyl of salicyl alcohol. Two new salicin analogues have been enzymatically synthesized by transglycosylation reactions: (a) by the reaction of Bacillus macerans cyclomaltodextrin glucanyltransferase with cyclomaltohexaose and salicyl alcohol, followed by reactions with alpha amylase and glucoamylase to give D-glucopyranose attached by an alpha-linkage to the phenolic hydroxyl of salicyl alcohol as the major product, alpha-salicin; and (b) by the reaction of Leuconostoc mesenteroides B-742CB dextransucrase with sucrose and salicyl alcohol, followed by reactions with dextranase and glucoamylase to give alpha-d-glucopyranose attached to the primary alcohol hydroxyl of salicyl alcohol as the major product, alpha-isosalicin.

Platanionosides D-J: megastigmane glycosides from the leaves of Alangium platanifolium (Sieb. et Zucc.) Harms var. platanifolium Sieb. et Zucc

From the leaves of Alangium paltanifolium var. platanifolium, collected in Fukuoka Prefecture, twelve further megastigmane glycosides were isolated. Seven of them, named platanionosides D-J (1-7), were found to be new compounds. Their structures were elucidated from spectroscopic evidence and their absolute structures were determined from beta-D-glucosylation-induced shift trends of 13C-NMR and by application of a modified Mosher's method.