118627-52-4Relevant articles and documents
Large-scale purification of unstable, water-soluble secologanic acid using centrifugal partition chromatography
Yeon, Sung Hum,Jeon, Je-Seung,Um, Key An,Kim, Chul Young,Ahn, Young-Joon
, p. 487 - 492 (2018)
Introduction: Secologanic acid, a major secoiridoid in the flower buds of Lonicera japonica, is a fragile, highly polar compound that readily changes to epivogeloside or vogeloside after being dissolved in methanol. Thus, it is very difficult to obtain secologanic acid on a large-scale. Objective: To develop a centrifugal partition chromatography (CPC) method for large-scale purification of secologanic acid with high purity from the flower buds of L. japonica. Methods: After fractionation with Diaion HP-20 macroporous resin, 30% methanol eluent was purified by CPC with a ternary biphasic solvent system with ethyl acetate/isopropanol/water (6:4:10, v/v/v). CPC was performed separately twice with the same solvent system, first in descending mode and second in ascending mode. Results: After the first CPC operation, a secologanic acid enriched fraction (586?mg) was obtained from 3?g of crude extract, and secologanic acid (206?mg) was isolated with a purity over 93% in the subsequent ascending mode with the same solvent system from a 586?mg enriched fraction. In addition, it was confirmed that epivogeloside and vogeloside were reversely converted to secologanic acid in an aqueous acidic solution. Conclusion: These results demonstrate that CPC is a simple, effective, and rapid method for the purification of secologanic acid in the flower buds of L. japonica.
Iridoids, XXI. - Synthesis of Secologanin
Tietze, Lutz F.,Henke, Stephan,Remberg, Gerd
, p. 1413 - 1427 (2007/10/02)
Acid-catalyzed reaction of natural secologanin (1) with ethylene glycol to 5a, followed by acetylation gave the peracetylated acetal 5b in almost quantitative yield.Oxidation of 5b with equimolar or catalytic amounts of osmium tetraoxide afforded stereoselectively the diol 6 as main product (31percent resp. 28percent) besides recovered starting material. 5b was cleaved with lead tetraacetate to give 96percent of the aldehyde 10.Reaction of 10 with triphenylphosphonio-methanide led to the labelled secologanin derivative -5b and the pyran 12 in a 27percent and 52percent yield, respectively.Acid-catalyzed transacetalization of -5b to -5c, base-catalyzed solvolysis of the acetate groups to -5d and subsequent acid-catalyzed cleavage of the acetal gave secologanin (-1).To determine its configuration at C-9, 6 was transformed via 8a to the tricyclic system 8d, which was independently synthesized via a photocycloaddition of the galactose derivative 13 and diformylacetate 14.