Norditerpenoid alkaloids from the processed tubers of Aconitum carmichaeli

Four new and five known norditerpenoid alkaloids were isolated from the processed tubers of Aconitum carmichaeli. The new alkaloids are 14-O-cinnamoylneoline (3), 14-O-anisoylneoline (4) 14-O-veratroylneoline (5), and lipo-14-O-anisoylbikhaconine (8). The known alkaloids are neoline (1), 14-O-acetylneoline (2), foresaconitine (6), crassicauline A (7), and lipohypaconitine (9). Alkaloids 2, 6, and 7 were isolated from this plant for the first time. The structures of the new alkaloids were established by spectroscopic and chemical methods.     

弯距翠雀花中二萜生物碱的结构鉴定

从弯距翠雀花(Delphinium campylocentrum Maxim.)全草中分离得到7种二萜生物碱, 其中弯翠生(1)和弯翠亭(2)为两个新的C₁₉-二萜生物碱, 其余5个为已知的二萜生物碱. 化合物1和2的结构通过现代波谱技术, 包括二维核磁共振谱和高分辨质谱, 予以了确证.     

New C18-diterpenoid alkaloids from Delphinium anthriscifolium var. savatieri

Five new C18-diterpenoid alkaloids, anthriscifolcines A (1), B (2), C (3), D (4), and E (5), together with a known C19-diterpenoid alkaloid delcorine (6), were isolated from the whole herb of Delphinium anthriscifolium var. savatieri. The structures of these new alkaloids were established on the basis of spectral data (1D- and 2D-NMR, HR-ESI-MS).     

Novel Alkaloids from Stemona sessilifolia

Two new alkaloids, sessilifolines A ( 1 ) and B ( 2a ), were isolated from the stems of Stemona sessilifolia, together with three known alkaloids, tuberstemonine ( 3 ), sessilifoliamide A ( 4 ), and stemoninoamide ( 5 ). Their structures were established by mass‐spectrometric and spectroscopic methods, especially 2D‐NMR techniques.     

Alkaloids from the Roots of Stemona tuberosa

Four new alkaloids, didehydrotuberostemonine A ( 1 ), stemoninone ( 2 ), tuberostemospiroline ( 3 ), and tuberostemonine L ( 4 ), together with seven known alkaloids, were isolated from the roots of Stemona tuberosa. Their structures were elucidated on the basis of spectroscopic analysis. The known alkaloids were identified as 2‐oxostenine ( 5 ), tuberostemonine ( 6 ), sessilifoliamide H ( 7 ), tuberostemonone ( 8 ), didehydrotuberostemonine ( 9 ), bisdehydrostemoninine ( 10 ), and tuberostemoamide ( 11 ).     

Diterpenoid Alkaloids from Delphinium tatsienense

Three new C₂₀‐diterpenoid alkaloids, along with twenty‐two known alkaloids, were isolated from the whole herbs of Delphinium tatsienense. The new alkaloids include a vakognavine‐type C₂₀‐diterpenoid alkaloid, designated as tatsienenseine A ( 1 ), and two hetisine‐type C₂₀‐diterpenoid alkaloids, designated as tatsienenseines B ( 2 ) and C ( 3 ). Their structures were elucidated by IR, HR‐ESI‐MS, 1D‐ and 2D‐NMR analyses.     

Two new diterpene alkaloids from Delphinium chrysotrichum

Chemical investigation on the ethanol extract from the whole plants of Delphinium chrysotrichum resulted in the isolation of two new diterpene alkaloids named delphatisine A (1) and delphatisine B (2), respectively. The structures of the new compounds were deduced on the basis of their spectral data (IR, HREIMS, EIMS, 1D, 2D-NMR). This is the first report on the isolation of diterpenoid alkaloids from the D. chrysotrichum.     

New proaporphines from the bark of Phoebe scortechinii

The phytochemical study of the bark of Malaysian Phoebe scortechinii (Lauraceae) has resulted in the isolation and identification of two new proaporphine alkaloids; (+)-scortechiniine A (1) and (+)-scortechiniine B (2) together with two known proaporphines; (-)-hexahydromecambrine A (3), (-)-norhexahydromecambrine A (4), and one aporphine; norboldine (5). Structural elucidations of these alkaloids were performed using spectroscopic methods especially 1D and 2D (1)H and (13)C NMR.     

Two new alkaloids from Miliusa cuneata

Two new isoquinoline alkaloids, 2,10-dimethoxy-3,11-dihydroxy-5,6-dihydroprotoberberine (1) and 1,9-dihydroxy-2,11 -dimethoxy-4,5-dihydro-7-oxoaporphine (2), together with thirteen known alkaloids, were isolated from the ethanolic extracts of the stem and leaves of Miliusa cuneata (Graib). Their structures were elucidated predominantly by spectral evidence.     

N-cyanomethylnorboldine: a new aporphine isolated from Alseodaphne perakensis (Lauraceae)

A phytochemical study of the bark of Alseodaphne perakensis has yielded three aporphine alkaloids: the new compound N-cyanomethylnorboldine (1), and the two known alkaloids N-methyllaurotetanine (2) and norboldine (3). The isolation was achieved by chromatographic techniques and the structural elucidation was performed via spectral methods, notably 1D- and 2D-NMR, UV, IR, and HRFABMS. The vasorelaxation activity of compound 1 has been studied.     

Neonaucline, a new indole alkaloid from the leaves of Ochreinauclea maingayii (Hook. f.) Ridsd. (Rubiaceae)

A new indole alkaloid; neonaucline (1), along with six known compounds-Cadamine (2), naucledine (3), harmane, benzamide, cinnamide and blumenol A-were isolated from the leaves of Ochreinauclea maingayii (Rubiaceae). In addition to that of compound 1, (13)C-NMR data of cadamine (2) and naucledine (3) were also reported. Structural elucidations of these alkaloids were performed using spectroscopic methods especially 1D- and 2D-NMR, IR, UV and LCMS-IT-TOF. The excellent vasorelaxant activity on isolated rat aorta was observed for the alkaloids 1-3 after injection of each sample at 1 × 10(-5) M.     

Alkaloidal constituents of Tinospora crispa

Phytochemical investigations of the stems of Tinospora crispa led to the isolation of one new aporphine alkaloid, N-formylasimilobine 2-O-beta-D-glucopyranoside (1), along with six known alkaloids, N-formylasimilobine 2-O-beta-D-glucopyranosyl-(1 --> 2)-beta-D-glucopyranoside (2) (tinoscorside A), N-formylanonaine (3), N-formyldehydroanonaine (4), N-formylnomuciferine (5), N-demethyl-N-formyldehydronornuciferine (6), magnoflorine (7), paprazine (8), N-trans-feruloyltyramine (9), and cytidine (10). The structure of new compound 1 was deduced on the basis of spectroscopic data.     

直缘乌头中新的C19—二萜生物碱的结构研究

从直缘乌头（Aconitum transsectum Diels.）根中分离得到4个新的乌头碱型 C_(19)-二萜生物碱。由光谱法（IR, ~1H NMR, ~(13)C NMR, 2D-NMR, MS）确定其 结构为:8-O-乙基滇乌碱（8-O-ethylyunaconitine） (1)、去氮乙基查斯曼宁（N- deethyl chasmanine）(2)、直缘乌碱丁（transconitine D）(3)和直缘乌碱戊（ transconitine E）(4)。     

New bisbenzylisoquinoline alkaloids from Cocculus laurifolius

Two new bisbenzylisoquinoline alkaloids, alpha, alpha'-dioxo-7'-O-demethylstebisimine (1) and 7'-O-demethylstebisimine (2), along with 14 known alkaloids, were isolated from the roots of Cocculus laurifolius. These alkaloids were characterized mainly by spectroscopic methods.     

Three new diterpenoid alkaloids from roots of Aconitum ouvrardianum HAND.-MAZZ

A new C(19)-diterpenoid alkaloid, ouvrardiantine (1) and two new C(20)-diterpenoid alkaloids, ouvrardiandines A (2) and B (3) were isolated from the root of Aconitum ouvrardianum HAND.-MAZZ. The structure of the new alkaloids was established on the basis of spectral data (1D- and 2D-NMR, HR-MS).     

New cholinesterase inhibiting bisbenzylisoquinoline alkaloids from Cocculus pendulus

Phytochemical investigation on Cocculus pendulus (J. R. & G. FORST.) resulted in the isolation of two new and three known bisbenzylisoquinoline alkaloids. The structures of the new alkaloids, kurramine-2'-beta-N-oxide (1) and kurramine-2'-alpha-N-oxide (2), were elucidated with the help of spectroscopic techniques. The cholinesterase inhibitory activities of these bisbenzylisoquinoline alkaloids are reported here for the first time.     

Daphnoldines A and B,Two New Yuzurine Alkaloids with a Four‐Ring System,from the Fruits of Daphniphyllum oldhami

Two new yuzurine alkaloids, daphnoldines A ( 1 ) and B ( 2 ), possessing a rare four‐ring system, were isolated from the fruits of Daphniphyllum oldhami. Their structures were established on the basis of extensive spectroscopic analyses. Daphnoldine A ( 1 ) is the first example of Daphniphyllum alkaloids bearing a hydroxymethyl group at C(14).     

Puberunine and puberudine, two new C18-diterpenoid alkaloids from Aconitum barbatum var. puberulum

Two C(18)-diterpenoid alkaloids, puberunine (1) and puberudine (2), together with four other new alkaloids, including the first examples having β-oriented substitution at C-3 and a rare chloro-substituent were isolated from Aconitum barbatum var. puberulum. Their structures were elucidated by spectroscopic methods. Puberunine and puberudine, which possess a unique rearranged E ring and an opened A ring, respectively, represent new subtypes of the C(18)-diterpenoid alkaloids. A plausible biosynthetic pathway of 1 and 2 was proposed.     

New Hydroxylated Spermidine Alkaloids from Pleurostylia opposita(WALL.) MERILL-METCALF

The leaves of a New Caledonian celastraceae, Pleurostylia opposita (WALL .) MERRILL -METCALF , have yielded three new spermidine alkaloids, 7-hydroxypleurostyline ( 1 ), 7-hydroxycelacinnine ( 2 ), and 7′-hydroxy-7′,8′-dihydropleurostyline ( 3 ), as minor basic constituents, together with three related alkaloids pleurostyline ( 4 ), celacinnine ( 5 ), and celallocinine ( 6 ).     

Three new C19-diterpenoid alkaloids from Delphinium giraldii

Further investigation of the roots of Delphinium giraldii DIELS led to the isolation of three new C(19)-diterpenoid alkaloids, giraldines G (1), H (2), and I (3). The structures of 1-3 were established based on spectroscopic evidence.