New Diterpenoid Alkaloids from Aconitum recemulosum Franch.

Two new diterpenoid alkaloids, racemulosines A ( 1 ) and B ( 2 ), were isolated from the roots of Aconitum racemulosum Franch . The structures of the new alkaloids were elucidated by analysis of physical and spectroscopic data, and the structure of 1 was further confirmed by a single‐crystal X‐ray diffraction analysis. Furthermore, compound 1 , at 2.25?10^?4 mol/l, showed moderate activity against platelet aggregation induced by PAF (platelet‐activation factor).     

A New Diterpenoid Alkaloid from the Roots of a White‐Flowering Aconitum orientale Sample

From the roots of a white‐flowering Aconitum orientale Miller sample, collected in Artvin‐?av?at, Turkey, a new diterpenoid alkaloid named aconitorientaline ( 1 ) was isolated, along with the known diterpenoid alkaloids septentiriodine, lappaconitine, finaconitine, ranaconitine, puberanidine and delstaphinine (Fig.). The structure of 1 was established on the basis of ¹H‐ and ¹³C‐NMR, DEPT, ¹H,¹H‐COSY, NOESY, HSQC, and HMBC studies. All the known compounds were identified by comparison of their ¹H‐ and ¹³C‐NMR data and co‐TLC behavior with those of authentic samples.     

Secokaraconitine, A New Diterpenoid Alkaloid from Aconitum karacolicum

The known diterpenoid alkaloids karacoline, karakanine, songorine, napelline, 12-acetylnapelline, cammaconine, and a new 7,17-secoalkaloid of the lycoctonine type, secokaraconitine, were isolated from tubers of Aconitum karacolicum. An x-ray structure analysis of the new alkaloid was performed.     

Four New Nor‐Diterpenoid Alkaloids from Aconitum brachypodum

Four new C₁₉‐nor‐diterpenoid alkaloids, named brachyaconitines A–D ( 1 – 4 ), were isolated from the roots of Aconitum brachypodum Diels. Their structures were elucidated as 3‐O‐acetyl‐20‐deethyl‐20‐formylaconitine ( 1 ), 3‐O‐acetyl‐19,20‐didehydro‐20‐deethylaconitine ( 2 ), 3‐O‐acetyl‐8‐de(acetyloxy)‐7,8,17,20‐tetradehydro‐20‐deethyl‐7,17‐secoaconitine ( 3 ), and 1‐O‐methylflavaconitine ( 4 ) by means of MS, IR, 1D‐ and 2D‐NMR analyses. The structure of compound 1 was confirmed by an X‐ray diffraction experiment.     

Diterpenoid Alkaloids from Aconitum Nagarum var. Lasiandrum

Aconitum species have been used as a traditional chinese medicine having analgesic activity. Several groups 1-3 have studied the components of the roots of Aconitum nagarum var. lasiandrum W.T. Wang. Further chemical investigation of this plant led to isolate two new diterpenoid alkaloids, nagadine 1 and 14-benzoylsachaconitine 2. This type of norditerpenoid alkaloid has not been reported before.Nagadine 1, +43.0 (c, 0.00273, CHCl3), was isolated as white amorphous powder. The HREIMS of …     

New Diterpenoid Alkaloids from Aconitum liangshanicum

One new C₁₉‐diterpenoid alkaloid, named liangshantine ( 1 ), and three new C₂₀‐diterpenoid alkaloids, liangshansines A–C ( 2 – 4 , resp.), as well as eight known compounds, were isolated from the roots of Aconitum liangshanicum. The structures of these new alkaloids were elucidated by spectroscopic methods.     

Two New C20‐Diterpenoid Alkaloids from the Tibetan Medicinal Plant Aconitum naviculare Stapf

Two new C₂₀‐diterpenoid alkaloids named naviculine A ( 1 ) and naviculine B ( 2 ), were isolated from Aconitum naviculare Stapf . Their structures were established by spectral methods, especially 2D‐NMR spectra (¹H,¹H‐COSY, HMQC, HMBC, and NOESY) and DFT methods (at the B3LYP/6‐311++G(2d,p)//B3LYP/6‐31G(d) level), respectively. They were assayed for their anti‐HIV‐1 activity.     

A New Diterpenoid Alkaloid from Aconitum episcopale

A new diterpenoid alkaloid with an epoxy ring between C(3) and C(17) was isolated from Aconitum episcopale. The structure was elucidated on the basis of spectral and chemical evidence.     

Bis‐Diterpenoid Alkaloids from Aconitum tanguticum var. trichocarpum

Phytochemical investigation of the whole herbs of Aconitum tanguticum (Maxim .) Stapf var. trichocarpum Hand.‐Mazz . led to the isolation of one heteratisine‐hetidine‐type bis‐diterpenoid alkaloid, trichocarpidine ( 1 ), three hetidine‐hetisine type bis‐diterpenoid alkaloids, trichocarpinine A–C ( 2 – 4 , resp.), together with nine known compounds. Their structures were elucidated by spectroscopic analyses.     

Structure and Antiarhythmic Activity of 12-Acetyl-12-epinapelline, a New Diterpenoid Alkaloid from Aconitum soongoricum

The structure of the new diterpenoid alkaloid 12-acetyl-12-epinapelline that was isolated from the mother liquor of Aconitum soongoricum was established. The conformational state of ring A was analyzed. Spectral properties and data for the antiarhythmic activity were presented.     

Piepunine,A Novel Bis‐diterpenoid Alkaloid from the Roots of Aconitum piepunense

Further investigation on the roots of Aconitum piepunense led to the isolation of a novel bis‐diterpenoid alkaloid designated as piepunine ( 1 ). Its structure was established by extensive interpretation of its 1D‐ and 2D‐NMR data, high‐resolution ESI‐MS, and IR spectra. Piepunine represents the first example of an atisine–denudatine‐type bis‐diterpenoid alkaloids.     

Habaenines A and B,Two New Norditerpenoid Alkaloids from Aconitum habaense

Two new norditerpenoid alkaloids, habaenine A and B ( 1 and 2 ), together with two known compounds, were isolated from Aconitum habaense. The structures of the new compounds were elucidated on the basis of spectral analyses as (1α,6α,16β)‐8‐(acetyloxy)‐20‐ethyl‐13‐hydroxy‐1,6,16‐trimethoxy‐4‐(methoxymethyl)‐19‐oxoaconitan‐14‐yl 4‐methoxybenzoate ( 1 ) and (1α,6α,16β)‐8‐(acetyloxy)‐13‐hydroxy‐1,6,16‐trimethoxy‐4‐(methoxymethyl)‐aconitan‐14‐yl 4‐methoxybenzoate ( 2 ).     

Three New C19‐Diterpenoid Alkaloids from Aconitum transsectum

Three new C₁₉‐diterpenoid alkaloids, named aconitramines A ( 1 ), B ( 2 ), and C ( 3 ), were isolated from Aconitum transsectum. By UV, IR, 1D‐ and 2D‐NMR, and MS analyses, their structures were elucidated as 18‐methoxyvilmoraconitine, 18‐demethoxydolichotine A, and 18‐demethoxydolichotine B. Compound 1 is the second known C₁₉‐diterpenoid alkaloid with a three‐membered ring formed by C(8), C(9), and C(10).     

Two New C20‐Diterpenoid Alkaloids from Aconitum carmichaelii

Two new C₂₀‐diterpenoid alkaloids, named aconicarchamines A and B ( 1 and 2 , resp.), were isolated from Aconitum carmichaelii. By UV, IR, MS, and 1D‐ and 2D‐NMR analyses, their structures were elucidated as 14,17‐dihydro‐14,17‐dihydroxyajabicine and 15‐O‐acetyllassiocarpine. Compound 1 is the third C₂₀‐diterpenoid alkaloid with the lycoctine skeleton bearing an exocyclic C‐atom at C(14).     

A New Alkaloid from the Roots of Aconitum carmichaeli Debx.

A new diterpene alkaloid, 12‐epi‐15‐O‐acetyl‐17‐benzoyl‐16‐hydroxy‐16,17‐dihydronapelline ( 1 ), along with nine known diterpene alkaloids including yunaconitine ( 2 ), neoline ( 3 ), mesaconitine ( 4 ), beiwutine ( 5 ), chasmanine ( 6 ), songorine ( 7 ), 12‐epi‐napelline ( 8 ), foresticine ( 9 ), and 15α‐hydroxyneoline ( 10 ) were isolated from the roots of Aconitum carmichaeli Debx. The structure of compound 1 was elucidated by comprehensive spectroscopic analysis.     

Two New C19‐Diterpenoid Alkaloids with Anti‐inflammatory Activity from Aconitum iochanicum

Two new C₁₉ ‐diterpenoid alkaloids, 7,8‐epoxy‐franchetine ( 1 ) and N(19)‐en‐austroconitine A ( 2 ), were isolated from Aconitum iochanicum . Compound 1 was a new C₁₉ ‐diterpenoid alkaloid with a 7,8‐epoxy unit. Their structures were elucidated by comprehensive spectroscopic analyses including UV , IR , MS , 1D and 2D NMR . Biological activity tests indicated that two new compounds exhibited inhibitory activity against nitric oxide (NO ) production in LPS ‐activated RAW264 .7 macrophages. Compared with positive control, the two new compounds showed weak anti‐inflammatory effects with the inhibition rate of 27.3% and 29.2%, respectively.     

Five New C19‐Diterpenoid Alkaloids from Aconitum hemsleyanum

Five new C₁₉‐diterpenoid alkaloids, named hemsleyaconitines A–E ( 1 – 5 , resp.), were isolated from Aconitum hemsleyanum Pritz. By UV, IR, MS, 1D‐ and 2D‐NMR analyses, their structures were elucidated as 18‐dehydroxygeniculatine D ( 1 ), 6‐hydroxy‐14‐O‐veratroylneoline ( 2 ), 14‐O‐acetyl‐8‐ethoxysachaconitine ( 3 ), 18‐veratroylkaracoline ( 4 ) and 8‐O‐ethylaustroconitine B ( 5 ).     

Hemsleyaconitines F and G,Two Novel C19‐Diterpenoid Alkaloids Possessing a Unique Skeleton from Aconitum hemsleyanum

Hemsleyaconitines F and G ( 1 and 2 , resp.) were isolated from the EtOH extract of Aconitum hemsleyanum. Their structures were elucidated by extensive analyses of the IR, 1D‐ and 2D‐NMR, and MS data. The two C₁₉‐diterpenoid alkaloids 1 and 2 possess a novel skeleton, featuring a five‐membered D‐ring between C(9), C(13), C(14), C(15), and C(16), which is quite different from the previously isolated six‐membered D‐ring analogs.