Concerning the alkaloid eripine from Hunteria umbellata

Eripine, a new indole alkaloid, was isolated from the leaves of Hunteria umbellata. The spectral data of the alkaloid, of eripinic acid and the O-acetyl and 19, 20-dihydro derivatives of the alkaloid led to the structure II. Heating of II gave a mixture (ratio 3,5:1) of the known alkaloid erinine (I) and its stereoisomer, isoerinine (VII), which is not found in nature. The same mixture was obtained on heating either erinine or isoerinine.     

Indolalkaloids of Pleiocarpa talbotii Wernham. 145. Alkaloids

Besides talbotine ( 1 ) three new indole alkaloids, talpinine ( 2 ), talcarpine ( 3 ) and 16-epi-affinine ( 4 ) were isolated from the stem bark of Pleiocarpa talbotii Wernham. The structure of 2 was deduced by chemical degradation and by analyses of the spectra of the alkaloid and its derivatives. One of these derivatives is identical with talcarpine ( 3 ). The structures 2 and 3 are similar to that of macroline ( 14 ), a splitting product of the bisindole alkaloid villalstonine from Alstonia species. 16-epi-Affinine ( 4 ) was chemically correlated with the known alkaloid vobasine ( 19 ). Talpinine ( 2 ) and 16-epi-affinine ( 4 ) were also isolated from the root bark of Pleiocarpa talbotii.     

Two Novel Monoterpene Alkaloid Dimers from Incarvillea arguta

Two novel monoterpene alkaloid dimers, named argutanes A and B ( 1 and 2 , resp.), together with the known alkaloid boschniakine ( 3 ), were isolated from the roots of Incarvillea arguta. The structures were elucidated on the basis of 1D‐ and 2D‐NMR, as well as HR‐ESI‐MS data.     

Secondary Metabolites from Magnolia kachirachirai

Investigation of the root bark of Magnolia kachirachirai led to the isolation of a new sesquiterpene, kachirachirain ( 1 ), and a new aporphine alkaloid, kachirachiranine ( 2 ), together with 20 known compounds, of which dimethyl 4,4′‐methylenebis(4,1‐phenylene)diurethane ( 3 ) was isolated for the first time from a natural source. Their structures were elucidated by spectroscopic analysis.     

Peduncularistin,Triabunnin und Aristolarin,drei neue Indolalkaloide aus Aristotelia peduncularis (LABILL.) HOOK. F., 191. Mitteilung über organische Naturstoffe

Peduncularistine, Triabunnine and Aristolarine, Three Ne Indole Alkaloids from Aristotelia peduncularis (L_LABILL.) H_OOK, F. Peduncularistine ( 1 ), triabunnine ( 2 ) and aristolarine ( 3 ), three new indole alkaloids, have been isolated from Aristotelia peduncularis (L_ABILL.) H_OOK. F.; the structure and absolute configuration of 1 were elucidated on the basis of spectroscopic data and confirmed byt transformation of 1 into aristeserratine ( 4 ), a known alkaloid isolated from the same plant. The proposed structure 2 for the second alkaloid and its absolute configuration were established but spectroscopic means and by partial synthesis from 4 . The relative configuration of 3 was postulated on the basis of spectroscopic and biogenetic arguments.     

Isoquinoline alkaloids from Asimina triloba

A new aporphine glycoside, (-)-anolobine-9-O-β-D-glucopyranoside was isolated from the twigs of pawpaw (Asimina triloba) along with 7 known alkaloids including five aporphine alkaloids (anolobine, nornuciferine, norushinsunine, liriodenine, and lysicamine), a proaporhine alkaloid (stepharine), and a tetrahydrobenzylisoquinoline alkaloid (coclaurine). Among these compounds, nornuciferine, lysicamine, stepharine, and coclaurine are reported for the first time from this plant. The structure of the new compound was elucidated by spectroscopic methods, including 1?D, 2?D NMR, and HRESI-MS. The absolute configuration of compounds 1, 2, 7 and 8 was determined by CD experiment.     

Structure and Dynamic of Three Indole Alkaloids from the Campylospermum Genus (Ochnaceae)

A new indole alkaloid, calanthumindole ( 4 ), and three known biflavonoids, amentoflavone, sequoiaflavone, and podoscarpusflavone B, were isolated from Campylospermum calanthum (Ochnaceae). Calanthumindole is a new indole alkaloid of the serotobenine family characterized by the presence of a C?C bond between atoms C(7′) and C(8′) of the furan ring. This is the first compound to have a fully unsaturated furan ring among the members of this family. The combination of NMR and DFT allowed the determination and comparison of the 3D structures and relevant conformational characteristics of serotobenine ( 1 ), flavumindole ( 2 ), and calanthumindole ( 4 ).     

Alkaloids from Daphniphyllum longeracemosum

A new alkaloid, daphnilongeridine ( 1 ), together with six known alkaloids, daphmacropodine ( 2 ), daphmacrine ( 3 ), codaphniphylline ( 4 ), daphniyunnine A ( 5 ), daphniyunnine C ( 6 ), and daphniyunnine E ( 7 ), were isolated from the leaves and stems of Daphniphyllum longeracemosum. The so far elusive configuration at C(25) of daphmacropodine ( 2 ) was assigned on the basis of ROESY correlations.     

Chemical Constituents from the Stems of Mahonia Japonica

A new dihydroberberine alkaloid, 7,8‐dihydro‐8‐methoxyberberine ( 1 ), along with six known compounds including two dihydroberberine alkaloids, 7,8‐dihydro‐8‐hydroxyberberine ( 2 ) and oxyberberine ( 3 ) and four protoberberine alkaloids, berberine ( 4 ), palmatine ( 5 ), jatrorrhizine ( 6 ) and columbamine ( 7 ), were isolated from the stems of Mahonia japonica. These compounds were characterized and identified by physical and spectral evidence.     

A New Alkaloid from Lycopodium japonicum Thunb.

A new alkaloid, miyoshianine C ( 1 ), was isolated from the whole plants of Lycopodium japonicum Thunb. , together with the known four compounds α‐obscurine ( 2 ), lycodoline ( 3 ), miyoshianine A ( 4 ), and lucidioline ( 5 ). Their structures were elucidated on the basis of in‐depth spectroscopic analysis.     

Alkaloids of Arundo donax L. 13. The structure of a new dimeric indole alkaloid,arundanine

The structure of a new dimeric indole alkaloid, named arundanine, isolated from the roots of Arundo donax L. (Poaceae), was elucidated. Arundanine was identified as 3-(N,N-dimethylaminoethyl)-4-[3-(N,N-dimethylaminoethyl)indole-1-yl]-5-hydroxyindole on the basis of spectroscopic data and the transformation into the known alkaloid, arundamine.     

Macrocarpamin,ein neues Bisindolalkaloid aus Alstonia macrophylla WALL. 167. Mittelung über organische Naturstoffe

Macrocarpamine, a new bisindole alkaloid from Alstonia macrophylla WALL . A new bisindole alkaloid give the name (?)-macrocarpamine ( 3 ) was isolated from the bark of Alstonia macrophylla WALL . Under pyrolytic conditions 3 is cleaved into the two known bases (+)-pleiocarpamine ( 2 ) and (?)-anhydro macrosalhin-methin ( 5 ) (Scheme 1). The structure of 3 (including relative configuration) was deduced on the basis of chemical evidence and from its UV.-, IR.-, NMR.- and mass spectroscopic data.     

A New Coumarin and Carbazole Alkaloid from Clausena vestita D. D. Tao

Phytochemical investigation of the EtOH extract of Clausena vestita D. D. Tao led to the isolation of one new coumarin, clauslactone U ( 1 ), and one new carbazole alkaloid, clauszoline N ( 2 ), together with 28 known compounds. The structures of these compounds were established by using MS and 1D‐ and 2D‐NMR techniques, and by comparison with known analogues.     

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.     

Chingazumianine,a Novel Dichlorinated Alkaloid from Corydalis koidzumiana

A dichlorinated alkaloid with a novel skeleton, chingazumianine ( 1 ), was isolated from the herb Corydalis koidzumiana, and its structure elucidated by spectroscopic data and X‐ray crystallographic analysis. In citrate‐treated human platelet‐rich plasma (PRP), known compounds, i.e., protopine ( 2 ), (±)‐tetrahydropalmatine ( 3 ), and palmatine ( 4 ), isolated from this plant, showed significant inhibition of secondary aggregation induced by adrenaline in a concentration‐dependent manner, suggesting that the antiplatelet effects of these compounds is mainly due to an inhibitory effect on thromboxane formation.     

Two New Lycopodium Alkaloids from Lycopodium obscurum

Two new Lycopodium alkaloids, (+)‐cermizine D N‐oxide ( 1 ) and (8β)‐8‐(acetyloxy)obscurumine A ( 2 ), along with five known compounds, were isolated from the crude alkaloid portion of Lycopodium obscurum. Their structures were elucidated on the basis of spectroscopic data and chemical correlation. All of these alkaloids were tested in an assay for acetylcholine esterase (AChE) inhibitory activity.     

Alkaloids from Fritillaria Hupehensis

Phytochemical investigation of the bulbs of Fritillaria hupehensis resulted in the isolation and structural elucidation of a new highly conjugated alkaloid of veratramine type identified as 3β,23β-dihydroxy-7,12（14）-dien-5α- veratramin-6-one （1）, together with two known alkaloids, ebeinine （2） and zhebeinine （3）, which were isolated for the first time from F. hupehensis. The structures of alkaloids 1-3 were established by extensive 1D and 2D NMR spectral analyses.     

Alkaloid and Anthraquinone Derivatives Produced by the Marine‐Derived Endophytic Fungus Eurotium rubrum

Cultivation of the fungal strain Eurotium rubrum, an endophytic fungus that was isolated from the inner tissue of the semi‐mangrove plant Hibiscus tiliaceus, resulted in the isolation of one new dioxopiperazine alkaloid, 12‐demethyl‐12‐oxo‐eurotechinulin B ( 1 ), and one new anthraquinone derivative, 9‐dehydroxyeurotinone ( 2 ), together with ten known compounds including variecolorin J ( 3 ), eurotechinulin B ( 4 ), variecolorin G ( 5 ), alkaloid E‐7 ( 6 ), cryptoechinuline G ( 7 ), isoechinulin B ( 8 ), 7‐isopentenylcryptoechinuline D ( 9 ), 2‐O‐methyl‐9‐dehydroxyeurotinone ( 10 ), emodin ( 11 ), and emodic acid ( 12 ). The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data as well as by comparison with literature reports. Some of the purified compounds were evaluated for antibacterial, antifungal, and cytotoxic activities.     

Indolalkaloide aus den Blättern von Hedranthera barteri (Hook. f.) Pichon. 146. Mitteilung über Alkaloide

From the leaves of the West African plant (Apocynaceae Hedranthera barteri) has been isolated the phenolic (?)-desmethyl-vobtusine ( 3 ), alongside the already known bisindole alkaloids (?)-goziline ( 1 ) and (?)-vobtusine ( 2 ). The new alkaloid 3 has been spectroscopically characterised and correlated with (?)-vobtusine ( 2 ). Furthermore, the ‘monomeric’ alkaloids (?)-hedrantherine ( 4 ) and (?)-17-hydroxy-hedran-therine ( 5 ) were found in the leaves of H. barteri. Both of these alkaloids contain a cyclic semiacetal group. These bases and their derivatives possessing an unchanged β-anilinoacrylester group show, in the mass spectrometer, the same characteristic fragmentation as vincadifformine ( 11 ), whilst their 2,3-dihydroderivatives bear more of a resemblance to aspidospermine. From the strongly negative Cotton effect of 4 and 22 at 300–350 nm follows the absolute configuration in these bases of centre 12. Hedrantherine ( 4 ) represents the lower half of the bisindole type of vobtusine bases. The upper half has previously been encountered in form of the alkaloid beninine in the rootbark of H. barteri.     

Alkaloids from the Stems of Glycosmis pentaphylla

A new simple carbazole alkaloid, 4‐(7‐hydroxy‐3‐methoxy‐6‐methyl‐9H‐carbazol‐4‐yl)but‐3‐en‐2‐one ( 1 ), and two new dimeric carbazole alkaloids, bisglybomine B ( 2 ) and biscarbalexine A ( 3 ), together with seven known alkaloids, were isolated from the stems of Glycosmis pentaphylla. Their structures were elucidated by spectroscopic methods, especially 2D‐NMR techniques.