Cytotoxic Evaluation of Pungencine: A New Tropane Alkaloid from the Roots of Erythroxylum pungens O. E. Schulz

A new tropane alkaloid as well as a new substitution group, (3‐endo,8‐anti)‐8‐methyl‐8‐azabicyclo[3.2.1]oct‐3‐yl 4‐hydroxy‐3,5‐dimethoxybenzoate, called pungencine ( 1 ), was isolated from the roots of Erythroxylum pungens O. E. Schulz . The structure was elucidated by spectral analyses, including ¹H‐ and ¹³C‐NMR and 2D‐NMR techniques (¹H,¹H‐COSY, NOESY, DEPT, HMQC, and HMBC) and HR‐ESI‐MS. Furthermore, compound 1 was tested for cytotoxicity against several cell lines (Jurkat, HL‐60, U937, K562, KG‐1, and U266) and was determined not to inhibit cell viability at 10 μM .     

Chirality and numbering of substituted tropane alkaloids

The strict application of IUPAC rules for the numbering of tropane alkaloids is not always applied by authors and there is hence a lot of confusion in the literature. In most cases, the notation of 3, 6/7-disubstituted derivatives has been chosen arbitrarily, based on NMR and MS data, without taking into account the absolute configuration of these two carbons. This paper discusses the problem and the relevance of CD and NMR to determine molecular configurations. We report on the use of (1)H-NMR anisochrony (Δδ) induced by the Mosher's chiral auxiliary reagents (R)-(-)- and (S)-(+)-α-methoxy-α-trifluoromethyl-phenylacetyl chlorides (MTPA-Cl), to determine the absolute configuration of (3R,6R)-3α-hydroxy-6β-senecioyloxytropane, a disubstituted tropane alkaloid isolated from the aerial parts of Schizanthus grahamii (Solanaceae). These analytical tools should help future works in correctly assigning the configuration of additional 3, 6/7 disubstituted tropane derivatives.     

Micellar electrokinetic capillary chromatography for selected tropane alkaloid analysis in plant extract

Summary Micellar electrokinetic capillary chromatography was applied to the simultaneous analysis of six tropane alkaloids, including hyoscyamine and scopolamine. Successful results were obtained using a 30 mM boratephosphate buffer at basic pH (8.5) in the presence of 50 mM sodium dodecyl sulfate. The operating conditions, such as buffer concentration and pH, micelle concentration and organic modifier type and percentage were also discussed on the basis of the results given with a tropane alkaloid mixture. Addition of organic modifiers showed an improvement in separation efficiency and resolution. Moreover, hyoscyamine and littorine, two positional isomers, were only resolved by the addition of organic solvents such as methanol or acetonitrile. The optimized conditions were finally applied to the analysis of tropane alkaloids found in genetically transformed root cultures ofDatura candida x D. aurea. Dedicated to Professor Werner Haerdi on the occasion of his 70^th birthday.     

Organometallic enantiomeric scaffolding: organometallic chirons. Total synthesis of (-)-Bao Gong Teng A by a molybdenum-mediated [5 + 2] cycloaddition

Bao Gong Teng A, an optically active tropane alkaloid with hypotensive and miotic activity isolated from the Chinese herb Erycibe obtusifolia Benth, was synthesized by an "organometallic chiron" strategy in which single enantiomers of TpMo(CO)(2)(eta(3)-pyridinyl) complexes are produced in quantity and then elaborated easily and efficiently to generate, after demetalation, highly enantiopure advanced synthetic intermediates possessing the tropane core.     

石杉碱O的结构鉴定

蛇足石杉[Huperziaserrata(Thunb.)Trev.]中,R~f与石杉碱甲相近部位分离得到一个新生物碱,经IR,MS,1D和2DNMR确定了其化学结构,为一个有内氢键烯醇型新的lycopodine类生物碱,命名为石杉碱O(HuperzineO)。     

Cohirsine - a novel isoquinolone alkaloid from

A novel alkaloid, cohirsine (1) was isolated from . Its structure has been investigated by extensive NMR studies including 2D NMR experiments. Its stereochemistry has been determined by 2D NOESY and NOE difference measurements.     

A cage-monoterpene indole alkaloid from Alstonia scholaris

An unprecedented cage-like alkaloid, scholarisine A was isolated from the leaves of Alstonia scholaris and its structure determined on the basis of 1D and 2D NMR, FTIR, UV, and high-resolution mass spectroscopic data. This alkaloid might be derived from picrinine via oxygenation, rearrangement, and lactonization.     

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.     

Lihouidine, a novel spiro polycyclic aromatic alkaloid from the marine sponge Suberea n. sp. (Aplysinellidae, Verongida)

An investigation of a new species of sponge from the genus Suberea collected at Lihou Reef in the Coral Sea afforded lihouidine, an unprecedented cytotoxic spiro nonacyclic polyaromatic alkaloid. The structure of the alkaloid, which was racemic, was determined by a combination of 1D and 2D NMR techniques and single-crystal X-ray structural analysis.     

Confolidine, a New Alkaloid from the Aerial Part of Convolvulus subhirsutus

A new tropane alkaloid was isolated from the aerial part of Convolvulus subhirsutus (Convolvulaceae, morning-glory). The structure was established as (±)3-vanillyl-N-formylnortropane based on spectral data.     

C19-二萜生物碱贡乌生的结构研究

毛茛科植物贡嘎乌头 ( Aconitum liljestrandii)具有镇痛、镇静、祛风湿等功效 ,产于我国西藏东部及四川西部 [1] .我们从其块根中分得 1 8个单体 ,其中 1 6个为已知生物碱 [2 ,3] ,2个为新生物碱 [3] .本文报道新的 C19-二萜生物碱贡乌生 ( Liljestrandisine) 1的结构 .1　实验部分1 .1　仪器与试剂　 Boetius微量熔点测定仪 ;Nicolet FTIR2 0 0 SXV型红外光谱仪 ,KBr压片 ;BrukerAC- E2 0 0和 Varian Unity INOVA40 0 /5 4核磁共振仪 ,溶剂为 CDCl3,TMS为内标 ;VG Autospec30 0 0型和 VG70 A型质谱仪 ;Pekin Polarimete…     

Vilmoraconitine, a novel skeleton C19-diterpenoid alkaloid from Aconitum vilmorinianum

A novel C₁₉-diterpenoid alkaloid vilmoraconitine (1) was isolated from the roots of Aconitun vilmorinianum. Its structure was mainly determined by MS, 2D NMR, and X-ray methods. This is the first aconitine-type C₁₉-diterpenoid alkaloid with one three-membered ring at C-8, C-9, and C-10.     

A Novel 19,21‐Secohetisan Diterpenoid Alkaloid from Aconitum tanguticum

A novel 19,21‐secohetisan diterpenoid alkaloid, tangutisine A ( 1 ), was isolated from Aconitum tanguticum (Maxim .) Stapf . Its structure was determined by HR‐EI‐MS and 1D‐ and 2D‐NMR spectroscopy and by comparison with the data of known 19,21‐secohetisan derivatives.     

A New Quinolizidine Alkaloid from Boehmeria siamensis

Boehmeria siamensis Craib is distributed in China, Vietnam, Laos and Thailand1. The whole plants of B. siamensis were used in folk medicine2,3. Previous studies on the plants of this genus led to the isolation of different compounds such as alkaloids, flavones, lignans, triterpenoids and its glycosides4-9. Some antimicrobial alkaloids were obtained from B. cylindrical4. In the investigation of the whole plant of B. siamensis, a new alkaloid, 3-(4-hydroxyphenyl)-4-(3-methoxy -4-hydroxypheny…     

Characterization of tropane and cinnamamide alkaloids from Scopolia tangutica by high‐performance liquid chromatography with quadrupole time‐of‐flight tandem mass spectrometry

Scopolia tangutica is a traditional Chinese medicine used for antispasmodic, anesthesia, analgesia, and sedation. Its medicinal activity is associated to alkaloid constituents, including tropane and cinnamamide types. Low content of alkaloids in plant makes them difficult to be isolated and identified. The present work developed an effective method to quickly characterize alkaloids from Scopolia tangutica by high‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry. Thirteen reference compounds were studied for their fragmentation pathways, including five tropane alkaloids and eight cinnamamide ones. Alkaloid constituent was analyzed by an optimized high‐performance liquid chromatography method and mass spectrometry analysis to achieve systematic characterization of alkaloids from Scopolia tangutica. As a result, 53 compounds were identified, including 21 tropane alkaloids (eight new ones), 18 caffeoyl ones (ten new ones) and 14 dicaffeoyl ones (seven new ones). It was important to provide rich information in phytochemical study and structure‐guided isolation of important compounds from this plant.     

Unusual reactions of a 7,17-seco-type C19-diterpenoid alkaloid derived from deltaline

Treatment of a 7,17-seco-type C19-diterpenoid alkaloid (3), prepared from deltaline (8), with triethylamine in either DMF or TEG (triethylene glycol) at 120 degrees C provided two interesting compounds 6 and 7. The structures of compounds 3, 6, and 7 were established based on extensive interpretations of their 1D and 2D NMR data. Compound 6, a lycoctonine-type C19-diterpenoid alkaloid, can be transformed from alkaloid 3 via Grob fragmentation, Prins reaction, and intramolecular disproportionation. The mechanism of the formation of compound 6 was confirmed by deuteration experiments. Product 7 was formed through a pinacol-like rearrangement of alkaloid 3.     

Succinic acid as a precursor of the tropane alkaloids

Summary The succinic acid used for the biosynthesis of the tropane alkaloids is probably included in their molecule as a whole, and forms the fragment of the alkaloid molecule consisting of carbon atoms 1, 7, 6, and 5.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 6, pp. 395–397, 1967     

Characterization of Atropa belladonna L. compounds by capillary electrophoresis-electrospray ionization-time of flight-mass spectrometry and capillary electrophoresis-electrospray ionization-ion trap-mass spectrometry

This short communication describes the characterization of seven tropane alkaloid compounds in Atropa belladonna L. Thus a rapid and easy CE-electrospray interface (ESI)-TOF-MS procedure is developed to analyze these compounds in a pharmaceutical preparations of A. belladonna L. leaf extract. Optimum electrophoretic separation is obtained using an alkaline solution of 60 mM ammonium acetate at pH 8.5 containing 5% isopropanol. Under the optimum CE-ESI-TOF-MS conditions several important compounds such as tropine, belladonnine, norhyoscyamine, apoatropine, hyoscyamine, 6beta-hydroxyhyoscyamine, and scopolamine have been simultaneously identified from A. belladonna L. CE-ESI-IT-MS has been used to discriminate the putative presence of littorine. The sensitivity, together with mass accuracy and true isotopic pattern of the TOF-MS, allowed the identification of a broad series of tropane alkaloid compounds present in pharmaceutical preparations of A. belladonna L. leaf extract.     

(+)‐(14β)‐14‐Ethylmatridin‐15‐one,a New Quinolizidine Alkaloid from the Poisonous Plant Oxytropis ochrocephala Bunge

A new matrine alkaloid derivative (+)‐(14β)‐14‐ethylmatridin‐15‐one ( 1 ) was isolated from the poisonous plant Oxytropis ochrocephala Bunge . The structure was established by spectroscopic methods, including extensive 1D‐ and 2D‐NMR experiments.     

Violatinctamine, a new heterocyclic compound from the marine tunicate Cystodytes cf. violatinctus

A new alkaloid designated violatinctamine and four known metabolites were isolated from the tunicate Cystodytes cf. violatinctus collected in Kenya. Violatinctamine has a unique heterocyclic skeleton, which combines a benzothiazole unit and a dihydroisoquinoline unit. The structure of violatinctamine was elucidated by interpretation of MS results as well as 1D and 2D NMR spectra of the alkaloid and of its O,O′-dimethyl derivative. Analysis of the spectral information also implies that violatinctamine exists as a mixture of two tautomers—the imino-phenol and the amino quinone-methide.