neoline and napelline

A new denudatine-type C

Topics: Aconitine; Aconitum; Alkaloids; Diterpenes; Molecular Structure; Plant Extracts; Spectrum Analysis

Diterpene alkaloids neoline (1), napelline (2), isotalatizidine (3), karakoline (4), senbusine A (5), senbusine C (6), aconitine (7) and taurenine (8) were identified from Aconitum napellus L. subsp. firmum, four (2-4, 6) of which are reported for the first time from this plant. The structures were determined by means of LC-MS, 1D and 2D NMR spectroscopy, including (1)H-(1)H COSY, NOESY, HSQC and HMBC experiments. Electrophysiological effects of the isolated compounds, together with nine diterpene alkaloids previously obtained from Aconitum toxicum and Consolida orientalis were investigated on stable transfected HEK-hERG (Kv11.1) and HEK-GIRK1/4 (Kir3.1 and Kir3.4) cell lines using automated patch clamp equipment. Significant blocking activity on GIRK channel was exerted by aconitine (7) (45% at 10 μM), but no blocking activities of the other investigated compounds were detected. The tested compounds were inactive on hERG channel in the tested concentration. The comparison of the previously reported metabolites of A. napellus subsp. firmum and compounds identified in our experiment reveals substantial variability of the alkaloid profile of this taxon.

Topics: Aconitine; Aconitum; ERG1 Potassium Channel; Ether-A-Go-Go Potassium Channels; G Protein-Coupled Inwardly-Rectifying Potassium Channels; HEK293 Cells; Humans; Molecular Structure; Plant Extracts; Potassium Channel Blockers; Ranunculaceae

Aconitum jaluense Komar. (Ranunculaceae) is one of the Aconitum plants growing in Korean peninsula. An investigation of the alkaloidal constituents of this species led to the isolation of seven C19-norditerpenoid and a C20-diterpenoid alkaloid. Three of them have been identified as neoline, mesaconitine, and hypaconitine, which were isolated from this plant collected from Mt. Bultasan in the north part. The other five alkaloids were determined as lipomesaconitine, lipohypaconitine, 15alpha-hydroxyneoline, hokbusine A, and napelline, which have not been found in this plant. Structures of those alkaloids were determined on the basis of their spectral data. It is of interest to note that a comparison of the present work and the previous report showed some differences in the alkaloidal contents.

Topics: Aconitine; Aconitum; Alkaloids; Diterpenes; Korea; Plant Extracts; Plant Roots; Spectrophotometry, Infrared