Leptopyrine,new alkaloid from Leptopyrum fumarioides L. (Ranunculaceae)

A new type of isoquinoline alkaloid leptopyrine was isolated from the aerial parts of Leptopyrum fumarioides L. (Ranunculaceae) of Mongolian origin. The known alkaloids protopine and thalifoline were isolated for the first time from this the species. All structures were established by physical and spectral analyses.     

Phenolic Compounds from Scorzonera tomentosa L.

From the subaerial parts of S. tomentosa L. (Asteraceae), two new dihydroisocoumarins, compounds 1 and 2 , a new phthalide, 3 , and a new stilbene derivative, 4 , were isolated, together with four known compounds, (±)‐hydrangenol ( 5 ), (?)‐hydrangenol 4′‐O‐β‐glucoside ( 6 ), (±)‐hydramacrophyllol A ( 7 ), and (±)‐hydramacrophyllol B ( 8 ). All secondary metabolites were identified on the basis of physicochemical, spectroscopic, and mass‐spectrometric data. The known compounds 5 – 8 were isolated for the first time from this species.     

Phenolic Compounds in the Flowers of Lavatera trimestris L. (Malvaceae)

JPC – Journal of Planar Chromatography – Modern TLC - Plants of the Malvaceae family are very rich in phenolic compounds. TLC, 2D TLC, and RP HPLC have been used for qualitative...     

Withanolide Compounds from the Flower of Datura metel L.

Three new withanolide compounds named baimantuoluoline A ( 1 ), B ( 2 ), and C ( 3 ) and the two known withanolides withafastuosin E ( 4 ) and withametelin C ( 5 ) were isolated from the fraction exhibiting activity for psoriasis in the flower of Datura metel L. The three new structures were determined as (5α,6α,7α,12β,15β,22R)‐6,7‐epoxy‐5,12,15‐trihydroxy‐1‐oxowitha‐2,24‐dienolide ( 1 ), (5α,6β,15β,22R)‐ 5,6,15,21‐tetrahydroxy‐1‐oxowith‐24‐enolide ( 2 ), and (5α,6β,12β,22R)‐5,6,12,21‐tetrahydroxy‐27‐methoxy‐1‐oxowitha‐2,24‐dienolide ( 3 ) on the basis of extensive spectroscopic data (HR‐ESI‐MS, ¹H‐ and ¹³C‐NMR, ¹H,¹H‐COSY, HSQC, HMBC, and NOESY) (withanolide=22‐hydroxyergostan‐26‐oic acid δ‐lactone).     

New Spirostanol Sulfonate from the Rhizomes of Helleborus thibetanus(Ranunculaceae)

A new spirostanol sulfonate, spirost-5,25(27)-dien-1β,3β-diol 1-sulfonate(1), was isolated from the rhi-zomes of Helleborus thibetanus(Ranunculaceae), and the structure was identified on the basis of a detailed spectros-copic analyses, including 2D NMR spectrometry, IR and HRESI-MS.     

Flavonoid Glycosides from Ranunculus chinensis Bge.

Four new flavonoid glycosides, 3‐O‐[α‐L ‐arabinopyranosyl‐(1→2)‐β‐D ‐galactopyranosyl]‐7‐O‐β‐D ‐glucopyranosylkaempferol ( 1 ), 3‐O‐(α‐L ‐arabinopyranosyl‐(1→2)‐{4‐O‐[(E)‐caffeoyl]‐β‐D ‐galactopyranosyl})‐7‐O‐β‐D ‐glucopyranosylquercetin ( 2 ), 3‐O‐{2‐O‐[(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→2)‐β‐D ‐galactopyranosyl}‐7‐O‐β‐D ‐glucopyranosylkaemperfol ( 3 ), and 3‐O‐{2‐O‐[(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→2)‐β‐D ‐galactopyranosyl}kaempferol ( 4 ), together with two known compounds were isolated from the aerial parts of Ranunculus chinensis Bge . The structures of the new glycosides were determined on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR, and ESI‐MS techniques, and chemical methods.     

Synthesis of Heterocyclic Compounds from Metallated Unsaturated Compounds and Isothiocyanates. (Review)

Novel syntheses of heterocyclic compounds resulting from reactions of metallated acetylenes, allenes, and conjugated dienes with isothiocyanates and from reactions of the latter with strong bases are reviewed.     

Diterpenoid and Phenolic Compounds from Juncus effusus L.

A novel diterpene, named effusenone A ( 1a ), which is the first reported rosane‐type diterpene from a Juncaceae plant, and three novel phenolic compounds, 5‐(hydroxymethyl)‐1‐methylphenanthrene‐2,7‐diol ( 4 ), 1‐methylpyrene‐2,7‐diol ( 5 ), and 7‐methoxy‐8‐methylpyren‐2‐ol ( 6 ) were isolated from the stem of Juncus effusus L. by normal‐phase and reversed‐phase silica gel column chromatography. Their structures were identified by spectroscopic methods, especially 2D‐NMR techniques.     

Oxygen-containing Heterocyclic Compounds from 1,5-Diketones. (Review)

Literature and characteristic experimental data correlated in the review concern the intramolecular cyclization by various means of substituted 1,5-diketones of the acyclic, semi-, and bicyclic series, proceeding to the formation of oxygen-containing heterocycles, such as pyrans, pyrylium salts, di- and tetrahydrofurans, and their condensed analogs, aroylfurans etc.     

One Alkenylphenol and Steroids from the Aquatic Plant Monochoria Vaginalis

Two new compounds have been isolated from the whole plant of Monochoria vaginalis and characterized as: (10Z)‐1‐(2,6‐dihydroxyphenyl)octadec‐10‐en‐1‐one ( 1 ) (20R, 24R)‐campest‐5‐ene‐3β, 4β‐diol ( 2 ) together with nine known ones. The structures of these compounds were elucidated on the basis of spectral data and chemical evidence.     

Optimization Method for Phenolic Compounds Extraction from Medicinal Plant (Juniperus procera) and Phytochemicals Screening

Juniperus procera is a natural source of bioactive compounds with the potential of antitumor, antimicrobial, insecticidal, antifungal, and antioxidant activities. An optimization method was developed for total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) in leaf and seed extract of Juniperus procera. Organic solvents (methanol (99.8%), ethanol (99%), and acetone (99.5%)), and deionized water (DI) were used for extraction. The estimation of TPC, TFC, and TTC in plant materials was carried out using UV-spectrophotometer and HPLC with the standards gallic acid, quercetin, and tannic acid. Recovery of TPC in leaf extract ranged from 2.9 to 9.7 mg GAE/g DW, TFC from 0.9 to 5.9 mg QE/g DW, and TTC ranged from 1.5 to 4.3 mg TA/g DW while the TPC value in the seed extract ranged from 0.53 to 2.6 mg GAE/g DW, TFC from 0.5 to 1.6 mg QE/g DW, and TTC ranged from 0.5 to 1.4 mg TA/g DW. This result revealed that methanol is the best solvent for recovery of the TPC value (9.7 mg) from leaf extract in comparison to other solvents. Ethanol recorded the highest result of TFC (5.9 mg) in leaf extract among the solvents whereas acetone was the best for TTC yield recovery from leaf extract (4.3 mg). In the case of the seed extract, ethanol was the best solvent for both TPC (2.6 mg), and TFC (1.6 mg) recovery in comparison to other solvents. Total tannin content in methanol resulted in significant recovery from seed extract (1.4 mg). Separation and quantification of gallic acid, quercetin, and tannic acid in plant materials were undertaken using HPLC. Gallic acid in leaf and seed of J. procera ranged from 6.6 to 9.2, 6.5 to 7.2 µg/g DW, quercetin from 6.3 to 18.2, 0.9 to 4.2 µg/g DW, and tannic acid from 16.2 to 29.3, 6.6 to 9.3 µg/g DW, respectively. Solvents have shown a significant effect in the extraction of phenolic compounds. Moreover, phytochemicals in plant materials were identified using GC-MS and resulted in very important bioactive compounds, which include anti-inflammatory, antibacterial, and antitumor agents such as ferruginol, phenanthrene, and n-hexadecanoic acid. In conclusion, the optimal solvent for extraction depends on the part of the plant material and the compounds that are to be isolated.     

New Dithiocarbamate Compounds from Organotin(IV)

Abstract

A series of new organotin(IV) dithiocarbamate compounds of type R_nSn (S₂CNR′R″)_4-n (n = 2, 3; R = dimethyl, dibutyl, diphenyl, triphenyl and tert-butyl; R′ = methyl, ethyl, benzyl; R″ = isopropyl, ethyl, ethanol) have been successfully synthesized. Elemental analysis showed that the percentage of the elements conformed to the general formula of these compounds. The important peaks of the infrared spectra for the stretching mode ν(C?N), ν(C?S), and v(Sn-S) for the compounds were observed in the area of 1440–1480 cm^?1, 940–1000 cm^?1, and 340–90 cm^?1, respectively. The ¹³C NMR spectra showed the most important peak for N¹³CS₂ chemical shifts were observed in the range 190–210 ppm. X-ray single crystal studies for several structures of these compounds showed that the chelating mode of the dithiocarbamate groups to the central tin atoms were either bidentate or anisobidentate.

GRAPHICAL ABSTRACT     

Characterization of Bioactive Compounds of Opuntia ficus-indica (L.) Mill. Seeds from Spanish Cultivars

Opuntia ficus-indica (L.) Mill. is the Cactaceae plant with the greatest economic relevance in the world. It can be used for medicinal purposes, animal nutrition, production of biofuels and phytoremediation of soils. Due to its high content of bioactive compounds, the prickly pear has antioxidant, antimicrobial and anticancer properties. The aim of this study was to determine the polyphenolic, fatty acid and amino acid profile and characterize the antioxidant capacity of seeds of seven Spanish prickly pear cultivars. A total of 21 metabolites, mainly phenolic acids and flavonols, were identified using ultraperformance liquid chromatography photodiode detector quadrupole/time-of-flight mass spectrometry (UPLC-PDA-Q/TOF-MS). Significant differences were found in the phenolic concentrations of the investigated varieties. The highest amount of phenolic compounds (266.67 mg/kg dry matter) were found in the “Nopal espinoso” variety, while the “Fresa” variety was characterized by the lowest content (34.07 mg/kg DM) of these compounds. In vitro antioxidant capacity was positively correlated with the amount of polyphenols. The amino acid composition of protein contained in prickly pear seeds was influenced by the variety. Glutamic acid was the predominant amino acid followed by arginine, aspartic acid and leucine, independent of prickly pear variety. Overall, 13 different fatty acids were identified and assessed in prickly pear seeds. The dominant fatty acid was linoleic acid, with content varying between 57.72% “Nopal ovalado” and 63.11% “Nopal espinoso”.     

Comparison of Volatile Organic Compounds of Sideritis romana L. and Sideritis montana L. from Croatia

A study on the headspace volatile organic compounds (VOCs) profile of native populations of Sideritis romana L. and Sidertis montana L., Lamiaceae, from Croatia is reported herein, to elucidate the phytochemical composition of taxa from this plant genus, well-known for traditional use in countries of the Mediterranean and the Balkan region. Headspace solid-phase microextraction (HS-SPME), using divinylbenzene/carboxene/polydimethylsiloxane (DVB/CAR/PDMS) or polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber, coupled with gas chromatography-mass spectrometry (GC-MS) was applied to analyze the dried aerial parts of six native populations in total. Furthermore, principal component analysis (PCA) was conducted on the volatile constituents with an average relative percentage ≥1.0% in at least one of the samples. Clear separation between the two species was obtained using both fiber types. The VOCs profile for all investigated populations was characterized by sesquiterpene hydrocarbons, followed by monoterpene hydrocarbons, except for one population of S. romana, in which monoterpene hydrocarbons predominated. To our knowledge, this is the first report on the VOCs composition of natural populations of S. romana and S. montana from Croatia as well as the first reported HS-SPME/GC-MS analysis of S. romana and S. montana worldwide.     

A bis-bithiophene from Tridax procumbens L. (Asteraceae)

The ethyl acetate soluble part of hexane extract of Tridax procumbens yielded a new bis-bithiophene named tridbisbithiophene along with four known terpenoids: taraxasteryl acetate, beta-amyrenone, lupeol and oleanolic acid, which have never been reported so far from Tridax procumbens. The structures of all the isolated constituents were elucidated with the aid of 1D-NMR spectroscopy whereas, the structure of new constituent tridbisbithiophene was confirmed via COSY and HMBC interactions.     

Anticoagulant, Antiherpetic and Antibacterial Activities of Sulphated Polysaccharide from Indian Medicinal Plant Tridax procumbens L. (Asteraceae)

The sulphated polysaccharide from the widespread Tridax procumbens plant was studied for the anticoagulant, antiherpetic and antibacterial activity. The anticoagulant activity was determined by the activated partial thromboplastin time assay. The sulphated polysaccharide from T. procumbens represented potent anticoagulant reaching the efficacy to heparin and chondroitin sulphate. Moreover, the sulphated polysaccharide extracted from T. procumbens was found non-toxic on Vero cell lines up to the concentration of 200 μg/ml. Sulphated polysaccharide exhibited detectable antiviral effect towards HSV-1 with IC(50) value 100-150 μg/ml. Furthermore, sulphated polysaccharide from T. procumbens was highly inhibitory against the bacterial strains Vibrio alginolyticus and Vibrio harveyi isolated from oil sardine.