A (−)‐norephedrine‐based molecularly imprinted polymer for the solid‐phase extraction of psychoactive phenylpropylamino alkaloids from Khat (Catha edulis Vahl. Endl.) chewing leaves

A molecularly imprinted polymer (MIP) was prepared using (?)‐norephedrine as the template, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross‐linker and chloroform as the porogen. The MIP was used as a selective sorbent in the molecularly imprinted solid‐phase extraction (MIP‐SPE) of the psychoactive phenylpropylamino alkaloids, norephedrine and its analogs, cathinone and cathine, from Khat (Catha edulis Vahl. Endl.) leaf extracts prior to HPLC‐DAD analysis. The MIP was able to selectively extract the alkaloids from the aqueous extracts of Khat. Loading, washing and elution of the alkaloids bound to the MIP were evaluated under different conditions. The clean baseline of the Khat extract obtained after MIP‐SPE confirmed that a selective and efficient sample clean‐up was achieved. Good recoveries (90.0–107%) and precision (RSDs 2.3–3.2%) were obtained in the validation of the MIP‐SPE‐HPLC procedure. The content of the three alkaloids in Khat samples determined after treatment with MIP‐SPE and a commercial Isolute C₁₈ (EC) SPE cartridge were in good agreement. These findings indicate that MIP‐SPE is a reliable method that can be used for sample pre‐treatment for the determination of Khat alkaloids in plant extracts or similar matrices and could be applicable in pharmaceutical, forensic and biomedical laboratories. Copyright © 2015 John Wiley & Sons, Ltd.     

Constituents of Catha edulis: Isolation and structure of cathidine D

Work which has recently appeared on the structures of Celastraceae alkaloids in addition to physical and chemical evidence adduced with respect to cathidine D permits formulation of structure 7a or 7b for this component of Catha edulis.     

Synthese und Strukturaufklärung von Merucathinon und Synthese von Cathinon. Inhaltsstoffe von Catha edulis FORSK

Synthesis and Structure Elucidation of Merucathinone and Synthesis of Cathinone. Constituents of Catha edulis FORSK . Starting from L-alanine, two constituents of Catha edulis FORSK ., (S)-4-amino-1-phenylpent-1-en-3-on ((S)- 3 ; merucathinone) and (S)-2-amino-1-phenylpropan-1-on ((S)- 1 ; cathinone) were synthesized.     

Synthese und Strukturaufklärung von Merucathin und Pseudomerucathin. Zwei Inhaltstoffe von Catha edulis FORSK

Synthesis and Structure Elucidation of Merucathine and Pseudomerucathine. Two Constituents of Catha edulis FORSK . Starting from L-alanine, two constituents of Catha edulis FORSK . (3R,4S)-4-amino-1-phenyl-1-penten-3-ol ((3R,4S)- 4 , merucathine) and (3S,4S)-4-amino-1-phenyl-1-penten-3-ol ((3S,4S)- 4 , pseudomerucathine) were synthesized.     

The Constituents of the Leaves of Chamaecyparis Formosensis Matsum

Forty one terpenoidal compounds were isolated from the essential oil of Chamaecyparis formosensis Matsum. The dominant component is α-pinene. Other major components include β-pinene, 3-carene, α-terpineol, γ-muurolene, and kaurene.     

Matrix Solid-Phase Dispersion for the HPLC–DAD Determination of Psychoactive Phenylpropylamino Alkaloids from Khat (Catha edulis Forsk) Chewing Leaves

A fast and simple procedure based on matrix solid-phase dispersion was developed for the extraction of psychoactive phenylpropylamino alkaloids; cathinone, cathine and norephedrine, from khat (Catha edulis Forsk) chewing leaves, a stimulant and drug of abuse plant. Determination of the alkaloids was carried out by high performance liquid chromatography with diode array detection. Several extraction parameters, such as type of dispersant, type and volume of elution solvent and the ratio of sample to sorbent material were evaluated and optimized. Mean recoveries ranging from 89 to 92 % with relative SD of less than 6 % were obtained. A marked diversity in the phenylpropylamino alkaloid content and composition was found in seventeen different cultivars of Ethiopian khat. ANOVA results showed the existence of significant differences between the alkaloids profiles among samples of different varieties from different geographical locations in Ethiopia. The proposed method is simpler, faster and comparably more efficient than the frequently reported maceration followed by liquid–liquid extraction but as good and efficient as ultrasonic assisted extraction followed by solid-phase extraction.     

Chemical composition of Helietta parvifolia and its in vitro anticholinesterase activity

The chemical composition of the essential oil and the n-hexane (Hex), Ethyl Acetate (EtOAc) and butanol (BuOH) extracts from the leaves of Helietta parvifolia were determined by detailed GC-MS analysis, spectroscopic and spectrometric data. Eighty-four compounds were identified, revealing a furoquinoline alkaloid-rich composition. The phytochemical analysis of the extracts allowed the isolation of eigth furoquinoline alkaloids. Retention indices in GC-MS for six of this alkaloids are reported for the first time. Furoquinoline alkaloids are acethylcholinesterase inhibitors. Thus, the essential oil and extracts were submitted to this in vitro assay. The EtOAc and BuOH extracts showed potent activity, with IC₅₀ of 9.7 and 12.9 μg mL^?1, respectively. Additionaly, a correlation of their chemical constituents, established by principal component analysis (PCA) demostrated a similar profile and a high content of alkaloids. It is for these reasons that we can assume that the alkaloid content in these extracts could be responsible for their anticholinesterase activity.     

Two Novel ent‐Kaurene Diterpenoids from Isodon rubescens

A novel 20‐nor‐ent‐kaurene diterpenoid, rubescensin N ( 1 ), and a new 7,20‐epoxy‐ent‐kaurene diterpenoid, rubescensin O ( 2 ), along with the seven known diterpenoids rabdoternins A–F and xerophilusin N, were isolated from Isodon rubescens collected in Jiyuan prefecture, Henan Province, China. Their structures were established by extensive spectroscopic analysis. Compound 1 is the first example of a naturally occurring 20‐nor‐ent‐kaurene diterpenoid from the Isodon genus plants.     

2-Phenyl-4-quinolinone Alkaloids from Casimiroa edulis Llave et Lex (Rutaceae)

 Three new 4-quinolinone alkaloids (5,6-dimethoxy-2-(3-methoxyphenyl)-1H-quinolin-4-one, 5,6-dimethoxy-2-(3,4-dimethoxyphenyl)-1H-quinolin-4-one, 5,6-dimethoxy-2-(2,5,6-trimethoxyphenyl)-1H-quinolin-4-one) were isolated from the leaves of Casimiroa edulis Llave et Lex (Rutaceae) cultivated in Egypt. Their structures were determined by UV/Vis, IR, ¹H and ¹³C NMR, and EI mass spectroscopy. The alkaloids were also detected in the kernels of the seeds.     

Chemical composition and evaluation of the antimicrobial activity of the essential oil from leaves of Eugenia platysema

This study describes the qualitative and quantitative chemical composition and evaluates the antibacterial activity of essential oil from Eugenia platysema leaves. Analysis by GC–FID and GC–MS allowed the identification of 22 compounds. Different from the other species of the Eugenia genus, the major compound found in the essential oil was the diterpene phytol (66.05%), being this the first report of the presence of this compound in the essential oils from Eugenia genus. The sesquiterpene elixene was the second most concentrated compound in the studied essential oil (9.16%). The essential oil from E. platysema was tested for its antibacterial activity against cell-walled bacteria and mollicute strains of clinical interest using the microdilution broth assay. The results showed that the essential oil of E. platysema was inactive until 1000 μg mL^?1 against tested bacteria.     

Evaluation of climatic factors on the yield and chemical composition of the essential oil of Myrocarpus frondosus

The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is a large tree, and its wood is used as a reservoir for distilled spirits, especially Cachaça. In this pioneering work, the essential oil was extracted monthly from the leaves of M. frondosus, for a period of 1 year. The essential oil was extracted by using hydrodistillation and the determination of the chemical composition of essential oil was performed by using the chromatographic techniques GC-FID and GC–MS. Thirty-three compounds were identified in the essential oil and bicyclogermacrene was the major compound. Through multivariate analysis, it was determined that β-caryophyllene, limonene and terpinen-4-ol were directly proportional to climatic factors. The yield of the oil was directly proportional to temperature and radiation.     

2-Phenyl-4-quinolinone Alkaloids from Casimiroa edulis Llave et Lex (Rutaceae)

Summary.  Three new 4-quinolinone alkaloids (5,6-dimethoxy-2-(3-methoxyphenyl)-1H-quinolin-4-one, 5,6-dimethoxy-2-(3,4-dimethoxyphenyl)-1H-quinolin-4-one, 5,6-dimethoxy-2-(2,5,6-trimethoxyphenyl)-1H-quinolin-4-one) were isolated from the leaves of Casimiroa edulis Llave et Lex (Rutaceae) cultivated in Egypt. Their structures were determined by UV/Vis, IR, ¹H and ¹³C NMR, and EI mass spectroscopy. The alkaloids were also detected in the kernels of the seeds. Received May 28, 2001. Accepted (revised) July 24, 2001     

Chemical evaluation and thermal analysis of the essential oil from the fruits of the vegetable species <Emphasis Type="Italic">Pimenta dioica</Emphasis> Lindl

The vegetal species Pimenta dioica Lindl, popularly known as Jamaican pepper, is a 6–15 m tall tree, which belongs to the Mirtaceae family. Its fruits have an essential oil of great economic value in the international market, due to its high level of eugenol (its major compound), which is largely used in chemical and pharmaceutical industries. In this work, the extraction of the essential oil from the fruits of Pimenta dioica Lindl was carried out by the hydrodistillation method, using a modified Clevenger system. It was observed that the volume of the extracted oil reaches a maximum at 4 h, with a yield of 2.7% (m/m). The essential oil was characterized by physico-chemical analyses, such as density, refraction index, ethanol solubility, color, and appearance, besides UV–vis and infrared spectroscopy and gas chromatography/mass spectrometry. Thus, eugenol was confirmed as the major component of the essential oil of Pimenta dioica Lindl (77%). The technique of differential scanning calorimetry (DSC) was used for the determination of boiling point of the sample of essential oil from the fruits of Pimenta dioica (L.).     

New alkaloids from <Emphasis Type="Italic">Casimiroa edulis</Emphasis> fruits and their pharmacological activity

The extract of Casimiroa edulis was investigated for antihypertensive activity. The ethanol and total alkaloids (in chloroform) extracts were found to have antihypertensive properties at doses of 500 and 200 mg/kg, respectively. Four quinolinone alkaloids were isolated and identified as: 2-(2′-hydroxy-4′-methoxyphenyl)-5,8-dimethoxy-3-propyl-1H-quinolin-4-one (1), 5,8-dimethoxy-2-(3′-methoxyphenyl)-3-propyl-1H-quinolin-4-one (2), 5,8-dimethoxy-2-(3′,4′-dimethoxyphenyl)-3-propyl-1H-quinolin-4-one (3), and 5,6-dimethoxy-2-(2′,5′,6′-trimethoxyphenyl)-1H-quinolin-4-one (4). Interestingly, compounds 1, 2, and 3 were found to be new alkaloids. The four isolated alkaloids showed antihypertensive activity at doses of 50, 100, 200, and 300 mg/kg, respectively. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 473–476, September–October, 2007.     

In vitro interactions of Peucedanum officinale essential oil with antibiotics

The chemical composition and antibacterial activity of Peucedanum officinale L. (Apiaceae) essential oil were examined, as well as the association between it and antibiotics: tetracycline, streptomycin and chloramphenicol. The interactions of the essential oil with antibiotics were evaluated using the microdilution checkerboard assay. Monoterpene hydrocarbons, with α-phellandrene as the dominant constituent, were the most abundant compound class of the essential oil of P. officinale. The researched essential oil exhibited slight antibacterial activity against the tested bacterial strains in vitro. On the contrary, essential oil of P. officinale possesses a great synergistic potential with chloramphenicol and tetracycline. Their combinations reduced the minimum effective dose of the antibiotic and, consequently, minimised its adverse side effects. In addition, investigated interactions are especially successful against Gram-negative bacteria, the pharmacological treatment of which is very difficult nowadays.     

Cocaethylene,the in vivo product of cocaine and ethanol,is a narcotic more potent than its precursors

The molecular conformation and supramolecular architecture of cocaethylene [systematic name: ethyl (1R ,2R ,3S ,5S )‐3‐benzoyloxy‐8‐methyl‐8‐azabicyclo[3.2.1]octane‐2‐carboxylate], C₁₈H₂₃NO₄, have been determined for the first time. Cocaethylene is a narcotic produced in vivo when cocaine and ethanol are administered concomitantly. The intra‐ and intermolecular features of cocaethylene and its less potent narcotic precursor cocaine are very similar. The only molecular difference is in the conformation of the methyl group of the ethoxycarbonyl group. Similar to cocaine, the carboxylate atoms and the α‐C atom are coplanar in cocaethylene, but the methyl C atom of the ethyl group is bent by ca 90° away from this plane in the narcotic reported here. The main supramolecular motif is a one‐dimensional chain stabilized by weak C—H…O contacts.     

Isolation and Identification of the Major Chemical Components Found in the Upper Parts of Teucrium Pofium Plants Grown in Khuzestan Province of Iran

Teucrium polium is a dwarf sub-shrub usually 30-60 cm high with many branches, which is fairly distributed throughout Iran, with its flowering being season mainly from April to July. The plant was collected during its flowering season in Baghmalek region in the North-East of Khuzestan province, Iran. After the identification of the genus, species and variety of the plant, the dried whole plant （flowers, fruits and the leaves） was steam distilled with different methods. The isolated essential oil was dried over anhydrous sodium sulphate and stored at 4-6 ℃. Analysis of the essential oil was carried out by GC-MS technique. At least 10 major components were identified （3-carene/α-pinene, β-phellandrene, limonene, germacrene, β-bourbonene, β-caryophylene, γ-muurolene, γ-elemene, spathulenol, β-eudesmol） （totally 97.02%）. Also, successive TLC and column chromatography of the essential oil resulted in the separation of four fractions. Based upon 1^H NMR, IR and mass spectra, the fractions with Rf=0.12 and 0.93 were determined as gualol and a mixture of α-pinene, β-phellandrene and limonene, respectively.     

Activity antifungal of the essential oils; aqueous and ethanol extracts from Citrus aurantium L.

Our study is about the essential oil of Citrus aurantium L. in Tunisia and its plant extract. The yield of this essential oil is 0, 56% but the yield of the extract of plant was 17.1% for the aqueous extract ant 18.3% for the ethanolic extract. The analysis of chemical composition by using GC and GC/MS showed the essential oil of C. aurantium L. species to be rich in monoterpenes such as α-terpineol, lianolyl acetate, linalool and limonene. The antifungal activity of this oil showed us an inhibition of the germination of mushrooms, in the same way we could note that the biologic activities are generally assigned to the chemotypes high content in oxygenated monoterpene.     

The Double‐Bond Configuration of Corynanthean Alkaloids and Its Impact on Monoterpenoid Indole Alkaloid Biosynthesis

Experimental evidence is provided for the coherence of the double‐bond geometry and the occurrence of “secondary cyclizations” in the biosynthesis of monoterpenoid indole alkaloids. Biosynthetically, akuammiline, C‐mavacurine, and Strychnos alkaloids are proposed to be derived from the corynanthean alkaloid geissoschizine, a key intermediate in the biosynthetic pathway of these monoterpenoid indole alkaloids. This process occurs by so‐called “secondary cyclizations” from geissoschizine or its derivatives. Although corynanthean alkaloids like geissoschizine incorporate E or Z double bonds located at C19–C20, the alkaloids downstream in the biosynthesis exclusively exhibit the E double bond. This study shows that secondary cyclizations preferentially occur with the E isomer of geissoschizine or its derivatives. This is attributed to the flexibility of the quinolizidine system of the corynanthean alkaloids, which can adopt a cis or trans conformation. For the secondary cyclization to take place, the cis‐quinolizidine conformation is required. Experimental evidence supports the hypothesis that the E double bond of geissoschizine induces the cis conformation, whereas the Z double bond induces the trans conformation, which prohibits secondary cyclization of the Z compounds.     

Chromatographic analysis,antimicrobial and insecticidal activities of the essential oil of Phlomis floccosa D. Don.

The present study was conducted to investigate for the first time the chemical composition and insecticidal and antimicrobial properties of Phlomis floccosa D. Don. essential oil isolated by hydro‐distillation of its aerial parts. Qualitative and quantitative analyses of the essential oil on the basis of gas chromatography and mass spectrometry (GC/FID and GC/MS) revealed the presence of 59 organic volatiles representing 86.9% of the total constituents. The major compounds were germacrene‐D (19.7%) followed by β‐caryophyllene (15.5%), caryophyllene oxide (8.3%), hexadecenoic acid (7.9%) and carvacrol (6.1%). The broth microdilution method was conducted to test the antimicrobial activity of the essential oil against five pathogens: Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Staphylococcus aureus, Bacillus subtilis and the yeast Candida albicans. The oil of P. floccosa D. Don. shows promising activity against the Gram‐positive bacteria S. aureus and B. subtilis and the yeast C. albicans (minimum inhibitory concentration = 625 μg.mL^?1). The effectiveness of the essential oil was assessed on both Tribolium confusum and Sitophilus zeamais pest insects and it was more pronounced against T. confusum, showing a moderate mortality of 47.5%.