Two new C20 hetisine-type diterpenoid alkaloids, spirafine III (1) and spirafine II (2), were isolated from the roots of Spiraea fritschiana var, parvifolia. Their structures were elucidated based on HRMS: IR and NMR ...Two new C20 hetisine-type diterpenoid alkaloids, spirafine III (1) and spirafine II (2), were isolated from the roots of Spiraea fritschiana var, parvifolia. Their structures were elucidated based on HRMS: IR and NMR spectral data, and chemical reaction.展开更多
Three new C20-diterpenoid alkaloids, designated as anthriscifolmines A-C （1-3）, together with two known alkaloids denudatine and delgramine, were isolated from the whole herb of Delphinium anthriscifolium var. savat...Three new C20-diterpenoid alkaloids, designated as anthriscifolmines A-C （1-3）, together with two known alkaloids denudatine and delgramine, were isolated from the whole herb of Delphinium anthriscifolium var. savatieri. The structures of these new alkaloids were elucidated on the basis of spectral data.展开更多
Three new napelline-type C20-diterpenoid alkaloids,named aconicarmichinium A and B trifluoroacetates（1 and 2） and aconicarmichinium C chloride（3）,were isolated from an aqueous extract of ＂fu zi＂,the lateral root...Three new napelline-type C20-diterpenoid alkaloids,named aconicarmichinium A and B trifluoroacetates（1 and 2） and aconicarmichinium C chloride（3）,were isolated from an aqueous extract of ＂fu zi＂,the lateral roots of Aconitum carmichaelii.Their structures were elucidated by extensive spectroscopic data analysis.Compounds 1-3 represent the first examples of napelline-type C20 diterpenoid alkaloid alcohol iminiums,of which the structures were fully characterized.In addition,transformation and equilibration between the alcohol iminiums（1-3） and the aza acetals la-3a were investigated by measurements of the NMR spectra in protic and aprotic deuterium solvents including alkali pyridine-d5,along with evaporation under reduced pressure and gradual additions of TFA,AcOH,and HC1.The results demonstrated that the transformation and equilibration were solvent-,base-,and acid-dependent.Especially,in aqueous biological fluid,these C20-diterpenoid alkaloids would more likely exist as the alcohol iminiums accompanied by anion counterparts in biosystems to increase their solubility, bioavailability, transportations, and functions.The absolute configurations of 1-3 were confirmed by X-ray crystallographic analysis of 2a.展开更多
Abstract: Two new hetisine-type C20-diterpenoid alkaloids named spiraqine (1) and 6-hydroxylspiraqine (2), and four known alkaloids, namely spiredine (3), spiradine A (4), spiradine B (5), and spirasine V/VI (6), were...Abstract: Two new hetisine-type C20-diterpenoid alkaloids named spiraqine (1) and 6-hydroxylspiraqine (2), and four known alkaloids, namely spiredine (3), spiradine A (4), spiradine B (5), and spirasine V/VI (6), were isolated from Spiraea japonica L. f. var. fortunei(Planchon) Rehd. The structures of the alkaloids were elucidated using nuclear magnetic resonance analysis (1H-NMR, 13C-NMR, DEPT, HMQC, and HMBC) and mass spectrometry data.展开更多
A bicyclo[2.2.2]octane C/D ring system, with a lactonic ring at C-8 and C-9, of the atisine-type C20-diterpenoid alkaloids, was successfully synthesized, using an oxidative dearomatization/intramolecular Diels-Alder r...A bicyclo[2.2.2]octane C/D ring system, with a lactonic ring at C-8 and C-9, of the atisine-type C20-diterpenoid alkaloids, was successfully synthesized, using an oxidative dearomatization/intramolecular Diels-Alder reaction.展开更多
文摘Two new C20 hetisine-type diterpenoid alkaloids, spirafine III (1) and spirafine II (2), were isolated from the roots of Spiraea fritschiana var, parvifolia. Their structures were elucidated based on HRMS: IR and NMR spectral data, and chemical reaction.
基金supported by the National Natural Science Foundation of China(No.30472075)the Excellent Ph.D.Dissertation Foundation of China(No.200367)
文摘Three new C20-diterpenoid alkaloids, designated as anthriscifolmines A-C （1-3）, together with two known alkaloids denudatine and delgramine, were isolated from the whole herb of Delphinium anthriscifolium var. savatieri. The structures of these new alkaloids were elucidated on the basis of spectral data.
基金Financial support from the National Natural Science Foundation of China (NNSFC Nos. 21132009, 30825044)the National Science and Technology Project of China (Nos. 2012ZX09301002002, 2011ZX0 9307-002-01)
文摘Three new napelline-type C20-diterpenoid alkaloids,named aconicarmichinium A and B trifluoroacetates（1 and 2） and aconicarmichinium C chloride（3）,were isolated from an aqueous extract of ＂fu zi＂,the lateral roots of Aconitum carmichaelii.Their structures were elucidated by extensive spectroscopic data analysis.Compounds 1-3 represent the first examples of napelline-type C20 diterpenoid alkaloid alcohol iminiums,of which the structures were fully characterized.In addition,transformation and equilibration between the alcohol iminiums（1-3） and the aza acetals la-3a were investigated by measurements of the NMR spectra in protic and aprotic deuterium solvents including alkali pyridine-d5,along with evaporation under reduced pressure and gradual additions of TFA,AcOH,and HC1.The results demonstrated that the transformation and equilibration were solvent-,base-,and acid-dependent.Especially,in aqueous biological fluid,these C20-diterpenoid alkaloids would more likely exist as the alcohol iminiums accompanied by anion counterparts in biosystems to increase their solubility, bioavailability, transportations, and functions.The absolute configurations of 1-3 were confirmed by X-ray crystallographic analysis of 2a.
文摘Abstract: Two new hetisine-type C20-diterpenoid alkaloids named spiraqine (1) and 6-hydroxylspiraqine (2), and four known alkaloids, namely spiredine (3), spiradine A (4), spiradine B (5), and spirasine V/VI (6), were isolated from Spiraea japonica L. f. var. fortunei(Planchon) Rehd. The structures of the alkaloids were elucidated using nuclear magnetic resonance analysis (1H-NMR, 13C-NMR, DEPT, HMQC, and HMBC) and mass spectrometry data.
基金the financial support provided by the National Science Foundation of China(No.81273387)
文摘A bicyclo[2.2.2]octane C/D ring system, with a lactonic ring at C-8 and C-9, of the atisine-type C20-diterpenoid alkaloids, was successfully synthesized, using an oxidative dearomatization/intramolecular Diels-Alder reaction.
