bluuebunny/crossref_metadata_2025 huggingface dataset:
Modification of Valencene by Bio- and Chemical Transformation
Authors: Asakawa Yoshinori , Hashimoto Toshihiro , Noma Yoshiaki , Furusawa Mai
Published: March 2019

Highly efficient production is discussed of nootkatone, the most important fragrant component of grapefruit and which possesses anti-obesity activity, from valencene, obtained from Valencia orange, by the green alga, Chlorella, and the fungi, Mucor, Botryospaeria and Botryodiplodia. The microorganisms introduce an oxygen atom at an allylic position to give secondary hydroxyl and keto groups. The presented methods are a cheap one step reaction, non-hazardous and very useful for the production of fragrant components from commercially available natural sesquiterpene hydrocarbons.
Enantioselective Synthesis of Natural Trinorsesquiterpene Tetralones by Chemo-enzymatic Approaches
Authors: Serra Stefano
Published: March 2019

The enantioselective syntheses of both the enantiomeric forms of the four natural tetralones 1a-d are here described. The aforementioned trinorsesquiterpenes were prepared starting either from substituted ( S)-3-arylbutanols 5a-c or from substituted ( S)-2-arylpropanols 7a-c. The latter chiral building blocks were in turn obtained through two different kinds of enzymatic transformations consisting of the baker's yeast mediated reduction of substituted ( E)-3-aryl-but-2-enals 4a-c and the lipase-mediated resolution of racemic 2-arylpropanols 7a-c, respectively. Further key steps of the presented syntheses were C1 and C2 homologation procedures as well as the ring closure of the substituted 4-aryl-pentanoic acids 3a-c. By these means the target compounds were obtained in good yields and with very high stereoisomeric purity. In addition, the trinorsesquiterpene schiffnerone-B was synthesized for the first time and its absolute configuration was unambiguously assigned.
Second Generation Synthesis of the Neo-Clerodane Diterpenoid Methyl Barbascoate
Authors: Hagiwara Hisahiro , Honma Naomi , Kinugawa Kimihiko , Sato Shota , Hoshi Takashi , Suzuki Toshio
Published: March 2019

The second generation total synthesis of the neo-clerodane diterpenoid, methyl barbascoate, was accomplished in seven or nine linear steps via double enol triflation and subsequent palladium catalyzed double carbonylation, followed by regioselective samarium diiodide mediated conjugate reduction.
Synthesis of a Key Intermediate, 10-Acetyl-7-(t-butyldiphenylsilyloxymethyl)-4-methylbicyclo[5.3.0]dec-4-en-1-ol, in the Synthesis of Pseudolaric Acid A
Authors: Nakashima Katsuyuki , Kikuchi Naoki , Takehara Tasuku , Shiozawa Takayuki , Takaoka Shigeru , Tori Motoo
Published: March 2019

10-Acetyl-7-( t-butyldiphenylsilyloxymethyl)-4-methylbicyclo[5.3.0]dec-4-en-1-ol was synthesized by aldol cyclization to a five-membered ring, epoxidation, samarium diiodide-induced ring opening, and the RCM reaction to the seven-membered carbocycle. This method has succeeded in constructing the desired stereochemistry in the synthesis of pseudolaric acid A.
Use of RCM Reactions for Construction of Eight-Membered Carbocycles and Introduction of a Hydroxy Group at the Juncture between Five- and Eight-Membered Carbocycles
Authors: Morimitsu Takahiro , Mizutani Reiko , Nakashima Katsuyuki , Saito Yoshinori , Tori Motoo
Published: March 2019

Model studies for total synthesis of YW3699 were carried out in order to introduce a hydroxy group at the ring juncture between 5- and 8-membered carbocycles. The five-membered ring part hydrazone and aldehyde with a cyclohexane ring were connected by the Shapiro reaction followed by conversion to diketones which were treated with IBX to afford hydroxylated models.
Synthetic Approach toward α-Aminomethyl-γ-butyrolactones from β-Lactam Synthons Elaborated by SmI2-mediated Reductive Coupling Reactions
Authors: Takahashi Masaki , Sudo Takahiro , Murata Yusuke , Sengoku Tetsuya , Yoda Hidemi
Published: March 2019

A simple and straightforward synthetic approach was developed to access a biologically important class of α-aminomethyl-γ-butyrolactones via a β-lactam synthon strategy involving successive ring-opening and lactonization processes from α-hydroxyethyl-substituted β-lactams that were elaborated by SmI2-mediated reductive coupling reaction.
Glucosylation of Taxifolin with Cultured Plant Cells
Authors: Shimoda Kei , Kubota Naoji , Hamada Manabu , Sugamoto Masahiro , Ishihara Kohji , Hamada Hatsuyuki , Hamada Hiroki
Published: March 2019

Cultured plant cells of Eucalyptus perriniana glucosylated taxifolin to its 3′- and 7- O-β-D-glucosides and 3′,7- O-β-D-diglucoside. On the other hand taxifolin was converted into 3′- and 7- O-β-D-glucosides by cultured cells of Nicotiana tabacum and Catharanthus roseus.
Synthesis of Resveratrol Glycosides by Cultured Plant Cells
Authors: Shimoda Kei , Hamada Manabu , Hamada Hatsuyuki , Takemoto Mai , Hamada Hiroki
Published: March 2019

Incubation of cultured cells of Glycine max with trans-resveratrol gave its 3-O-β-D- and 4′- O-β-D-glucosides. Cultured Gossypium hrsutum cells glycosylated trans-resveratrol to its 3-O-β-D-, 4′- O-β-D- and 3,4′- O-β-D-diglucosides. On the other hand trans-resveratrol was converted into cis-resveratrol 4′- O-β-D-glucoside together with trans-resveratrol 3- O-β-D-glucoside and trans-resveratrol 4′- O-β-D-glucoside by Eucalyptus perriniana.
A New Variant of Fused Cyclic Ether Synthesis Based on Ireland-Claisen Rearrangement and RCM
Authors: Domon Daisuke , Fujiwara Kenshu , Kawamura Natsumi , Katoono Ryo , Kawai Hidetoshi , Suzuki Takanori
Published: March 2019

A new variant of fused cyclic ether synthesis based on Ireland-Claisen rearrangement and ring-closing olefin metathesis (RCM) was developed. The Ireland-Claisen rearrangement and ring-closing olefin metathesis (RCM) was developed. The Ireland-Claisen rearrangement of a ( Z)-3-alkoxyprop-2-en-1-yl glycolate ester having a cyclic ether on the oxygen at C3 of the ( Z)-prop-2-en-1-yl group stereoselectively produced an anti-α,β-dialkoxyester which was successfully transformed to a fused bicyclic ether via a reaction sequence including RCM.
Synthetic Approaches to Tetracyclic Pyrrole Imidazole Marine Alkaloids
Authors: Imaoka Takuya , Iwata Makoto , Akimoto Takafumi , Nagasawa Kazuo
Published: March 2019

Oroidin derived pyrrole imidazole marine alkaloids (PIAs) are attractive targets for synthetic organic chemists because of their structural complexity and diversity as well as their interesting biological activities. A number of efforts have been carried out to develop strategies for the synthesis of these natural products. Members of PIAs ( eg., 2-7) which contain tetracyclic ring systems possessing characteristic cyclic guanidine or urea moieties show significant biological activities including anticancer activity and agonistic activity against the adrenoceptor. In this review investigations of the total synthesis of the representative tetracyclic PIAs dibromophakellin (2) and dibromophakellstatin (3) are described.
Lyngbouilloside and Related Macrolides from Marine Cyanobacteria
Authors: ElMarrouni Abdelatif , Kolleth Amandine , Lebeuf Raphael , Gebauer Julian , Prevost Sébastien , Heras Montserrat , Arseniyadis Stellios , Cossy Janine
Published: March 2019

Lyngbouilloside and the related macrolides lyngbyaloside lyngbyaloside B and lyngbyaloside C have attracted a lot of attention over the past decade due to their intriguing architecture their natural scarcity and their potential biological activities. This review aims to showcase the various strategies that have been used to access these natural products.
Enantioselective Total Synthesis of Otteliones A and B, Novel and Powerful Antitumor Agents from the Freshwater Plant Ottelia alismoides
Authors: Katoh Tadashi
Published: March 2019

Otteliones A and B isolated from the freshwater plant Ottelia alismoides have attracted significant attention because of their potential as novel anticancer agents. In this review four independent enantioselective total syntheses and one formal synthesis of these natural products are presented with particular focus on their methodology and strategy.
A New Approach to the Synthesis of Chiral Blocks for Cyclopentanoids
Authors: Gimazetdinov Airat M. , Ivanova Nadezhda A. , Miftakhov Mansur S.
Published: March 2019

A microreview is presented of the development by the authors of the original preparation of enantiomerically pure cyclopentane blocks from the racemic [2+2]-cycloadducts of 1,3-cyclopentadiene and its derivatives with dichloroketene.
Recent Applications and Developments of Organic Azides in Total Synthesis of Natural Products
Authors: Tanimoto Hiroki , Kakiuchi Kiyomi
Published: March 2019

Organic azides have been exploited since their discovery because of their high reactivities. Various organic reactions using azides have been synthetically applied in chemical biology pharmaceuticals medicinal and agricultural areas. In this review we present some recent applications and developments of organic azides in the total synthesis of natural products (mostly within five years) especially alkaloids. We focus not only on application examples of organic azides but also show their preparation methods including recently reported procedures concerning their decomposing and reducing methods in the syntheses of bioactive molecules.
Microbial Biotransformation of 16α,17-Epoxy-Ent-kaurane-19-oic acid by Beauveria Sulfurescens ATCC 7159-F
Authors: Furtado Ricardo A. , Gunaherath G. M. Kamal B. , Bastos Jairo K. , Gunatilaka A. A. Leslie
Published: March 2019

Biotransformation of 16α,17-epoxy- ent-kaurane-19-oic acid (1) by Beauveria sulfurescens ATCC 7159-F led to the production of a new ent-kaurane diterpenoid, 7β,17-dihydroxy- ent-kaur-15-en-19-oic acid (7), and four other ent-kauranes (8 - 11), all of which were identified as their methyl esters. Compounds 9 and 10 were found to be new stereoisomers. Structures of these were established by the extensive usage of their spectroscopic characteristics.
TLC-Image Analysis of Non-Chromophoric Tuberostemonine Alkaloid Derivatives in Stemona Species
Authors: Kongkiatpaiboon Sumet , Keeratinijakal Vichien , Gritsanapan Wandee
Published: March 2019

A simple, selective, precise, and accurate thin-layer chromatographic (TLC) image analytical method was developed and validated for simultaneous quantification of the major components in the root extracts of Stemona. tuberosa (tuberostemonine, tuberostemonine N and neotuberostemonine)), and S. phyllantha (tuberostemonine and tuberostemonine A). The analysis was performed by TLC on silica gel 60 F254 aluminum plates using a mixture of dichloromethane: ethyl acetate: methanol: ammonium hydroxide (50:45:4:1) as mobile phase. Post-derivatization was employed by dipping the TLC plate into Dragendorff's reagent to visualize the spots. Image analysis of the scanned TLC plate was performed to detect the contents of tuberostemonine derivatives. The polynomial regression data for the calibration plots showed good linear relationships within the concentration range of 2–7 μg/spot. The method gave satisfactory precision, accuracy, selectivity and could simultaneously quantify tuberostemonine, tuberostemonine A, tuberostemonine N and neotuberostemonine. Dried powdered roots of S. tuberosa grown in Thailand contained 1.31 + 0.28, 1.63 + 0.18 and 1.24 + 0.27% tuberostemonine, tuberostemonine N, and neotuberostemonine (dry weight), respectively, while S. phyllantha roots contained 1.39 + 0.14% tuberostemonine and 0.39 + 0.08 % tuberostemonine A (dry weight). The proposed method was simple, inexpensive, and more accessible to apply for many local authorities and small laboratories.
Two New Compounds from Gorgonian-associated Fungus Aspergillus sp
Authors: Xu Xin-Ya , Zhang Xiao-Yong , He Fei , Peng Jiang , Nong Xu-Hua , Qi Shu-Hua
Published: March 2019

One new γ-lactone derivative 5-hydroxy-3-isopropyl-4-methoxyfuranone (1) and one new lactam derivative dehydrated-marinamide (2), along with two known compounds marinamide (3) and marinamide methyl ester (4) were isolated from the fermentation broth of the marine gorgonian-associated fungus Aspergillus sp. SCSGAF0093. Their structures were elucidated on the basis of spectroscopic and spectrometric analysis. Compound 1 showed significant toxicity to brine shrimp (Artemia salina) with a median lethal concentration (LC50) of 1.25 μM, and 3 inhibited protein tyrosine phosphatase 1B (PTPlB) with a half maximal inhibitory concentration (IC50) of 23.3 μg/mL.
In Vitro Anti-proliferative Effect of Naturally Occurring Oxyprenylated Chalcones
Authors: Fiorito Serena , Epifano Francesco , Bruyère Celine , Kiss Robert , Genovese Salvatore
Published: March 2019

As a continuation of our ongoing studies aimed to depict the effects and mechanism of action of naturally occurring oxyprenylated phenylpropanoids and polyketides, in this paper we describe the synthesis and in vitro anti-proliferative effects of selected compounds belonging to the above cited classes of secondary metabolites on six cancer cell lines using the MTT colorimetric assay. Our study revealed that among the natural products tested, only oxyprenylated chalcones exhibited an appreciable effect (mean IC50 = 32 - 64 μM), while substituted alcohols, phenylpropenes, naphthoquinones, and aminoacid derivatives were by far less active or inactive.
7-O-Methylpelargonidin Glycosides from the Pale Red Flowers of Catharanthus Roseus
Authors: Tatsuzawa Fumi
Published: March 2019

Two new anthocyanidin glycosides were isolated from the pale red flowers of Catharanthus roseus ‘Equator Apricot with Red Eye’, and identified as 7- O-methylpelargonidin 3- O-[6- O-(α-rhamnopyranosyl)-β-galactopyranoside] and 7- O-methylpelargonidin 3- O-(β-galactopyranoside) by chemical and spectroscopic methods.
A Concise and Efficient Total Synthesis of α-Mangostin and β-Mangostin from Garcinia Mangostana
Authors: Xu Dandan , Nie Ying , Liang Xizhou , Ji Ling , Hu Songyuan , You Qidong , Wang Fan , Ye Hongchun , Wang Jinxin
Published: March 2019

The concise, efficient synthesis of α-mangostin is described in eight simple steps with 8.3% overall yield. Highlights include a practical approach to construct the isopentene groups and other diverse groups at C–2 and C–8 of the xanthene skeleton through Claisen rearrangement and Wittig reaction. Meanwhile the first total synthesis of β-mangostin is presented with a similar approach.
Biologically Active Secondary Metabolites from Asphodelus Microcarpus
Authors: Ghoneim Mohammed M. , Ma Guoyi , El-Hela Atef A. , Mohammad Abd-Elsalam I. , Kottob Saeid , El-Ghaly Sayed , Cutler Stephen J. , Ross Samir A.
Published: March 2019

Bioassay guided fractionation of the ethanolic extract of Asphodelus microcarpus Salzm.et Vivi (Asphodelaceae) resulted in the isolation of one new metabolite, 1,6-dimethoxy-3-methyl-2-naphthoic acid (1) as well as nine known compounds: asphodelin (2), chrysophanol (3), 8-methoxychrysophanol (4), emodin (5), 2-acetyl-1,8-dimethoxy-3-methylnaphthalene (6), 10-(chrysophanol-7’-yl)-10-hydroxychrysophanol-9-anthrone (7), aloesaponol-III-8-methyl ether (8), ramosin (9) and aestivin (10). The compounds were identified by 1D and 2D NMR and HRESIMS. Compounds 3, 6 and 10 were isolated for the first time from this species. Compounds 3 and 4 showed moderate to weak antileishmanial activity with IC50 values of 14.3 and 35.1 μg/mL, respectively. Compound 4 exhibited moderate antifungal activity against Cryptococcus neoformans with an IC50 value of 15.0 μg/mL, while compounds 5, 7 and 10 showed good to potent activity against methicillin resistant Staphylococcus aureus (MRSA) with IC50 values of 6.6, 9.4 μg/mL and 1.4 μg/mL respectively. Compounds 5, 8 and 9 displayed good activity against S. aureus with IC50 values of 3.2, 7.3 and 8.5 μg/mL, respectively. Compounds 7 and 9 exhibited a potent cytotoxic activity against leukemia LH60 and K562 cell lines. Compound 10 showed potent antimalarial activities against both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum with IC50 values in the range of 0.8-0.7 μg/mL without showing any cytotoxicity to mammalian cells.
A New Macrolide from a Marine-derived Fungus Aspergillus sp
Authors: Bao Jie , Xu Xin-Ya , Zhang Xiao-Yong , Qi Shu-Hua
Published: March 2019

A new 16-membered macrolide named aspergillide D (1), along with six known compounds, including two polyketones (2–3) and four alkaloids (4–7), were isolated from the culture broth of a marine-derived fungus Aspergillus sp. SCSGAF 0076. The structure of 1 was elucidated on the basis of NMR and mass spectra. Compound 5 showed an obvious inhibitory effect on influenza virus strains H1N1 and H3N2.
HPLC-MS and GC-MS Analyses Combined with Orthogonal Partial Least Squares to Identify Cytotoxic Constituents from Turmeric (Curcuma Longa L.)
Authors: Jiang Jianlan , Zhang Huan , Li Zidan , Zhang Xiaohang , Su Xin , Li Yan , Qiao Bin , Yuan Yingjin
Published: March 2019

We investigated the fingerprints of 48 batches of turmeric total extracts (TTE) by HPLC-MS-MS and GC-MS analyses and 43 characteristic peaks (22 constituents from HPLC-MS-MS; 21 from GC-MS) were analyzed qualitatively and quantitatively. An MTT {3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide} assay was implemented to measure the cytotoxicity of the TTE against HeLa cells. Then we utilized orthogonal partial least squares analysis, which correlated the chemical composition of the TTE to its cytotoxic activity, to identify potential cytotoxic constituents from turmeric. The result showed that 19 constituents contributed significantly to the cytotoxicity. The obtained result was verified by canonical correlation analysis. Comparison with previous reports also indicated some interaction between the curcuminoids and sesquiterpenoids in turmeric.
Determination of Antiplasmodial Activity and Binding Affinity of Selected Natural Products towards PfTrxR and PfGR
Authors: Munigunti Ranjith , Becker Katja , Brun Reto , Calderón Angela I.
Published: March 2019

In our study, the binding affinities of selected natural products towards PfTrxR, PfGR, human TrxR and human GR were determined using a mass spectrometry based ligand binding assay. The in vitro antimalarial activity and cytotoxicity of these ligands were also determined. Catharanthine, 11-(OH)-coronaridine, hernagine, vobasine and hispolone displayed antiplasmodial activity against PfK1 (IC50 = 0.996–3.63 μg/mL).
Wild Thymbra Capitata from Western Rif (Morocco): Essential Oil Composition, Chemical Homogeneity and Yield Variability
Authors: Bakhy Khadija , Benlhabib Ouafae , Faiz Chaouki Al , Bighelli Ange , Casanova Joseph , Tomi Felix
Published: March 2019

Essential oils (EO, 15 collective samples and 47 individual samples) of Thymbra capitata collected from Moroccan Western Rif were analyzed using gas chromatography (GC) in combination with retention indices (RI), gas chromatography-mass spectrometry (GC-SM) and 13C NMR spectroscopy. Twenty components were identified. Carvacrol (68.2%–85.9 %) was by far the major component of all the samples, while the content of thymol (0.1-0.3%) was very low. Other components present in appreciable amounts were γ-terpinene (up to 8.9%), p-cymene (up to 7.1%), linalool (up to 4.4%) and ( E)- β-caryophyllene (up to 4.1%). In contrast, the yield of EO varied drastically from sample to sample (0.5–3.7%). No correlation could be established between yield of EO and altitude, pH, chemical composition and granularity of the soil. Cultivation under controlled conditions is suggested to improve the quantitative characteristics of carvacrol-rich Moroccan T. capitata.
Chemical Compositions, Phytotoxicity, and Biological Activities of Acorus Calamus Essential Oils from Nepal
Authors: Satyal Prabodh , Paudel Prajwal , Poudel Ambika , Dosoky Noura S. , Moriarity Debra M. , Vogler Bernhard , Setzer William N.
Published: March 2019

Four essential oils from the leaf (P23) and rhizomes (P19, P22, P24) of Acorus calamus L., collected from various parts of Nepal, were obtained by hydrodistillation and analyzed by GC-MS. From a total of 61 peaks, 57 compounds were identified among the four essential oils accounting for 94.3%, 96.2%, 97.6%, and 94.1% of the oils, respectively. All of the essential oils were dominated by ( Z)-asarone (78.1%–86.9%). The essential oils also contained ( E)-asarone (1.9%–9.9%) and small amounts of γ-asarone (2.0–2.3%), ( Z)-methyl isoeugenol (1.5–2.0%), and linalool (0.2–4.3%). Allelopathic testing of the rhizome oil showed inhibition of seed germination of Lactuca sativa and Lolium perenne with IC50 values of 450 and 737 μg/mL, respectively. The rhizome essential oil demonstrated stronger seedling growth inhibition of L. perenne than of L. sativa, however. The rhizome oil also showed notable brine shrimp lethality ( LC50 = 9.48 μg/mL), cytotoxic activity (92.2% kill on MCF-7 cells at 100 μg/mL), and antifungal activity against Aspergillus niger (MIC = 19.5 μg/mL).
Review on Research of Suppression Male Fertility and Male Contraceptive Drug Development by Natural Products
Authors: Bajaj Vijay Kumar , Gupta Radhey S
Published: March 2019

Male contraceptive development in the present scenario is most viable aspect of research due to uncontrolled population growth in the world. In this respect investigators are busy to find out a safe male contraceptive drug. Researchers have started their finding for a suitable drug from natural sources because these are safe and easily acceptable for common man, most of natural sources are plants and their products. In this review 137 plants and their effects on reproduction and reproductive physiology are summarized. Some of them have intense effect on male reproductive system and do not produce any side effects. Reproductive toxicological studies are also important aspects of these kinds of researches, so it is important that drugs are safe and widely acceptable. An ideal male contraceptive can influence semen, testes, hormone level, accessory reproductive organs and general physiology of animals and produced some alterations. Many plants in this review are showing antifertility as well as antispermatogenic effects, so these may be used for further study for contraceptives development but it is important to find out the mechanism of reaction and further laboratory and clinical research on some plants are needed for final male contraceptive drug development. In conclusion this review will help for finding suitable plant products for male contraceptive clinical and laboratory studies.
Biscembranoids from the Marine Sponge Petrosia Nigricans
Authors: Nhiem Nguyen Xuan , Van Quang Ngo , Van Minh Chau , Thuy Hang Dan Thi , Le Tuan Anh Hoang , Tai Bui Huu , Yen Pham Hai , Hoai Nguyen Thi , Thung Do Cong , Van Kiem Phan
Published: March 2019

One new biscembranoid, petronigrione (1), and five known compounds, methyl tortuoate B (2), lobophytone U (3), lobophytone H (4), (24 S)-ergostane 3β,5α,6β,25tetraol-25-monoacetate (5), and (24 S)-ergostane-1β,3β,5α,6β,25-pentaol-25-monoacetate (6), were isolated from the methanol extract of the marine sponge Petrosia nigricans. Their structures were established on the basis of spectral and chemical evidence. The cytotoxicity of all compounds was evaluated by MTT assay on four human cancer cell lines, HepG2, KB, LU-1, and MCF-7. Compounds 1 and 2 exhibited moderate cytotoxic activities on the four human cancer cell lines with IC50 values ranging of 20.7 - 28.9 μg/mL.
Isolation of Cycloeucalenol from Boophone Disticha and Evaluation of its Cytotoxicity
Authors: Adewusi Emmanuel Adekanmi , Steenkamp Paul , Fouche Gerda , Steenkamp Vanessa
Published: March 2019

Boophone disticha (Amaryllidaceae) is widely used in traditional medicine in southern Africa. Several alkaloids, volatile oils and fatty acids have been isolated from the plant. However, there has been no literature report of a triterpene from B. disticha. Cycloeucalenol, a cycloartane triterpene, together with its regio-isomer, was isolated from the ethyl acetate extract of the bulbs using column chromatography and preparative thin layer chromatography. Structural elucidation was carried out using 1D and 2D NMR and mass spectroscopy. The MTT and neutral red assays were used to assess the cytotoxicity of the compound in human neuroblastoma (SH-SY5Y) cells. The compound was obtained as a mixture of two regio-isomers, which were separated for the first time by chromatographic optimization. Integration of the 1H NMR spectrum showed that cycloeucalenol and its regio-isomer were present in a ratio of 1.04:1. A dose-dependent decrease in cell viability was observed using both cytotoxicity assays. IC50 values of 173.0 ± 5.1 μM and 223.0 ± 6.4 μM were obtained for the MTT and neutral red assays, respectively, indicative of the low toxicity of the compound. This work describes for the first time, the presence of triterpene compounds from the genus Boophone.
Determination of C-23 Configuration in (20R)-23-Hydroxycholestane Side Chain of Steroid Compounds by 1H and 13C NMR Spectroscopy
Authors: Kicha Alla A. , Kalinovsky Anatoly I. , Antonov Alexander S. , Radchenko Oleg S. , Ivanchina Natalia V. , Malyarenko Timofey V. , Savchenko Alexander M. , Stonik Valentin A.
Published: March 2019

Epimeric (20 R,23 R)- and (20 R,23 S)-23-hydroxycholestane steroids were synthesized. Their structures were elucidated by extensive 1H and 13C NMR spectroscopy and application of the Mosher's method. All proton and carbon signals of the side chains were assigned. Based on these assignments spectral data allow the determination of the C-23 stereochemistry of (20 R)-23-hydroxycholestane side chains of the new natural steroids by comparison with spectra of the obtained model compounds. As a result, the C-23 configuration of two steroid compounds from the starfishes Lethasterias nanimensis chelifera and Lethasterias fusca was established.
Oxasetin from Lophiostoma sp. of the Baltic Sea: Identification, in silico Binding Mode Prediction and Antibacterial Evaluation against Fish Pathogenic Bacteria
Authors: Shushni Muftah Ali M. , Azam Faizul , Lindequist Ulrike
Published: March 2019

Because of the evolving resistance of microorganisms against existing antibiotics, there is an increasing need for new ones, not only in human, but also in veterinary medicine. The dichloromethane extract of a fungal strain of the genus Lophiostoma, isolated from driftwood collected from the coast of the Baltic Sea, displayed antibacterial activity against some fish pathogenic bacteria. Ergosterol epoxide (1), cerebroside C (2) and oxasetin (3) were isolated from the extract and structurally elucidated on the basis of spectroscopic data and chemical evidence. Compound 3 exhibited in vitro activity against Vibrio anguillarum, Flexibacter maritimus and Pseudomonas anguilliseptica with minimal inhibitory concentrations of 12.5, 12.5 and 6.25 μg/mL, respectively. Molecular docking studies were performed to understand the interaction of compound 3 with different macromolecular targets. Analysis of in silico results, together with experimental findings, validates the antimicrobial activity associated with compound 3. These results may be exploited in lead optimization and development of potent antibacterial agents.
Phytochemical Evaluation of Lythrum Salicaria Extracts and Their Effects on Guinea-Pig Ileum
Authors: Bencsik Tímea , Barthó Loránd , Sándor Viktor , Papp Nóra , Benkó Rita , Felinger Attila , Kilár Ferenc , Horváth Györgyi
Published: March 2019

n-Hexane, chloroform, ethyl acetate and 50% ethanol in water extracts prepared from the air-dried flowering parts of Lythrum salicaria L. were tested for in vitro pharmacological properties on Guinea-pig ileum, which is suitable for detecting a whole range of neuronal and smooth muscle effects. UHPLC-MS was used to evaluate polyphenol components of the extracts. In the ileum, the most prominent response (46.4% related to 0.5 μM histamine) of the extracts causing smooth muscle contractions were triggered by the 50% ethanol in water extract in a concentration-dependent manner. Atropine, indomethacin and PPADS plus suramin significantly reduced the contractile response caused by this extract. The strongest inhibition was due to atropine. The results suggest that L. salicaria extracts have a moderate muscarinic receptor agonist effect in Guinea-pig ileum and that prostanoids and purinoceptor mechanisms are involved to some extent. Therefore diluted extracts of L. salicaria p.o. could be used as a mild stimulant of gastrointestinal motility. The 50% ethanol in water extract was rich in polyphenols. n-Hexane, chloroform and ethyl acetate extracts failed to contain catechin, caffeic acid, quercetin-3-D-galactoside and rutin, but they all showed spasmogenic effects, and, therefore we do not think that these compounds could be involved in the spasmogenic activity.
Immunomodulatory Activities of α-Mangostin on Peripheral Blood Mononuclear Cells
Authors: Kasemwattanaroj Pimolkan , Moongkarndi Primchanien , Pattanapanyasat Kovit , Mangmool Supachoke , Rodpai Ekkarat , Samer Jutima , Konlata Julaporn , Sukapirom Kasama
Published: March 2019

Mangosteen ( Garcinia mangostana L.) a tropical fruit, has been used in traditional medicine. A frequently used part of mangosteen is the pericarp, containing a high content of xanthones. α-Mangostin, one of the major xanthone derivatives, exhibits a variety of actions, including antimicrobial, antioxidant, cytotoxic and antitumor; however, its function on the immune system is still equivocal. This study aimed to examine the immunomodulatory activities of α-mangostin on lymphocyte lineage and cytokine production in human peripheral blood mononuclear cells (PBMCs). The cytotoxic activity of α-mangostin was measured by MTT assay. The concentration of α-mangostin at 5.55 μg/mL resulted in a 50% survival of PBMCs, which was as potent a cytotoxic activity as that of paclitaxel. After 24 h of PBMCs culture, the percentages of T cells (CD3+), B cells (CD19+) and NK cells (CD3-CD16+CD56+) were not significantly changed by treatment with 1, 2 and 4 μg/mL of α-mangostin compared with untreated-PBMCs; in addition, the percentages of these lymphocytes treated with the combination of α-mangostin (1, 2 and 4 μg/mL) and the mitogen concanavalin A (ConA) was not significantly different from that of ConA-treated PBMCs. For cytokine secretion, α-mangostin (1, 2 and 4 μg/mL) did not significantly induce either proinflammatory cytokines (i.e., TNF-α and IL-1β) or cytokine of adaptive immunity (i.e., IL-2). The combination of α-mangostin (1, 2 and 4 μg/mL) and ConA did not significantly alter the relative difference of TNF-α and IL-1β compared with ConA-treated PBMCs; however, these combinations could significantly decrease the relative difference of IL-2 compared with ConA-treated PBMCs. These data indicated that α-mangostin was able to inhibit IL-2 release without interfering with human immune cells; therefore, further studies are necessary to investigate its effect on IL-2 production.
Antiplasmodial Quinones from the Rhizomes of Kniphofia Foliosa
Authors: Induli Martha , Gebru Meron , Abdissa Negera , Akala Hosea , Wekesa Ingrid , Byamukama Robert , Heydenreich Matthias , Murunga Sylvia , Dagne Ermias , Yenesew Abiy
Published: March 2019

Extracts of the rhizomes of Kniphofia foliosa exhibited antiplasmodial activities against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 3–5 μg/mL. A phenyloxanthrone, named 10-acetonylknipholone cyclooxanthrone (1) and an anthraquinone-anthrone dimer, chryslandicin 10-methyl ether (2), were isolated from the rhizomes, along with known quinones, including the rare phenylanthraquinone dimers, joziknipholones A and B. The structures of these compounds were determined based on spectroscopic data. This is the second report on the occurrence of the dimeric phenylanthraquinones in nature. In an in vitro antiplasmodial assay of the isolated compounds, activity was observed for phenylanthraquinones, anthraquinone-anthrone dimers and dimeric phenylanthraquinones, with joziknipholone A being the most active. The new compound, 10-acetonylknipholone cyclooxanthrone, also showed anti-plasmodial activity. In an in vivo assay, knipholone anthrone displayed marginal antimalarial activity.
In Vitro Anti-diabetic Activity of Sclerocarya Birrea and Ziziphus Mucronata
Authors: Da Costa Mousinho Nuno M.H. , van Tonder Jacob J. , Steenkamp Vanessa
Published: March 2019

Type 2 diabetes mellitus is on the increase worldwide. Current treatments possess undesirable side-effects and therefore investigations into alternative remedies, which may be cost-effective and devoid of such side-effects, are on-going. Aqueous and methanol extracts of the bark of Sclerocarya birrea (A. Rich.) Hochst. subsp. caffra (Sond.) Kokwaro (Anacardiaceae) and Ziziphus mucronata Willd. subsp. mucronata (Rhamnaceae) were subjected to testing in order to assess their in vitro anti-diabetic activity. Total polyphenolic content and antioxidant activity, as well as the effect on α-amylase, α-glucosidase and cytotoxicity, were measured. Furthermore, glucose uptake was evaluated in C2C12 myotubes, 3T3-L1 adipocytes and HepG2 hepatocarcinoma cells, and insulin secretion in RIN-m5F rat pancreatic β-cells. The extracts of both plants inhibited the activities of α-amylase and α-glucosidase in a concentration dependent manner, with results being comparable with the positive control, acarbose. All the extracts contained antioxidant activity, with the methanol extracts of S. birrea displaying the strongest free radical scavenging capacity (IC50 = 2.16 μg/mL). Most of the extracts were not cytotoxic to the cell lines with IC50 values > 100 μg/mL. Extracts of both plants significantly increased glucose uptake in C2C12, 3T3-L1 and HepG2 cells. However, insulin secretion from RIN-m5F cells was not altered. This study provides evidence that the plants possess in vitro anti-diabetic properties.
Secondary Metabolites from the Fungus Emericella Nidulans
Authors: Tarawneh Amer H. , León Francisco , Radwan Mohamed M. , Rosa Luiz H. , Cutler Stephen J.
Published: March 2019

A new polyketide derivative koninginin H (1), has been isolated from the fungus Emericella nidulans, together with koninginin E (2), koninginin A (3), trichodermatide B (4), citrantifidiol (5), (4 S,5 R)-4-hydroxy-5-methylfuran-2-one (6), the glycerol derivatives gingerglycolipid B (7), (2 S)-bis[9 Z,12 Z]-1- O, 2- O-dilinoleoyl-3- O-[α-D-galactopyranosyl-(1″→6′)β-D-galactopyranosyl]glycerol (8), (2 S)-bis[9 Z,12 Z]-1- O, 2- O-dilinoleoyl-3- O-β-D-galactopyranosylglycerol (9), the cerebroside flavuside B (10), and the known sterols β-sitosterol glucoside and ergosta-5,7,22-trien-3-ol. Their structures were established by extensive NMR studies (1H NMR, 13C NMR, DEPT, 1H–1H COSY, HSQC, HMBC) and mass spectrometry. The antibacterial, antimalarial, antifungal and antileishmanial activities of compounds 1–10 were examined and the results indicated that compound 4 showed good antifungal activity against Cryptococcus neoformans with an IC50 value of 4.9 μg/mL.
A New Glucuronolactone Glycoside Phoenixoside B from the Seeds of Phoenix Dactylifera
Authors: Azmat Sumbul , Ifzal Rehana , Mohammad Faryal Vali , Ahmad Viqar Uddin , Zahoor Aqib
Published: March 2019

A new glucuronolactone glycoside, phoenixoside B (1), has been isolated from the n-butanol soluble fraction of seeds of Phoenix dactylifera. The structure was characterized as 1-(1-ethyl-β-D-glucosyl)-4,5-diethyl-[α-D-glucofuranourono-6,3-lactone] on the basis of 1D and 2D-NMR spectroscopy and high-resolution mass spectrometry.
Antibacterial Activity of the Essential Oil of Heracleum Sibiricum
Authors: Miladinović Dragoljub L. , Ilić Budimir S. , Mihajilov-Krstev Tatjana M. , Nikolić Dejan M. , Cvetković Olga G. , Marković Marija S. , Miladinović Ljiljana C.
Published: March 2019

The composition and antimicrobial activity of the essential oil of Heracleum sibiricum L. (Apiaceae) was studied. The aerial part of plant was hydro-distilled and chemical composition of the essential oil was analyzed by GC and GC-MS. Forty-six compounds, corresponding to 95.12% of the total oil, were identified. Esters represented the major chemical class (69.55%) while the main constituents were octyl butanoate (36.82%), hexyl butanoate (16.08%), 1-octanol (13.62%) and octyl hexanoate (8.10%). Antibacterial activity of the essential oil and reference antibiotics against nine bacterial strains was tested by the broth microdilution method. The results of the bioassays showed that essential oil had slight antimicrobial activities against all tested microorganisms (MIC and MBC values were in the range of 2431.2 to 9724.8 μg/mL). Reference antibiotics were active in concentrations between 0.5 and 16.0 μg/mL. The results confirm that Gram-positive bacteria were more susceptible to the essential oil of H. sibiricum, in comparison with Gram-negative bacteria.
Essential Oils of Alpinia Rafflesiana and Their Antimicrobial Activities
Authors: Jusoh Shariha , Sirat Hasnah Mohd , Ahmad Farediah
Published: March 2019

The essential oils from the leaves, pseudostems, rhizomes and fruits of Alpinia rafflesiana were isolated by hydrodistillation. The oils were analysed by capillary GC and GC-MS. The most abundant components in the leaf oil were trans-caryophyllene (32.61%), caryophyllene oxide (8.67%), (2 E,6 Z)-farnesol (4.91%) and α-terpineol (4.25%), while 1,8-cineole (32.25%), myrcene (13.63%), α-terpineol (9.90%) and trans-caryophyllene (9.80%) were the main constituents in the pseudostem oil. The rhizome constituted of tetracosane (42.61%), τ-cadinol (7.46%), α-terpineol (6.71%) were the major components, whereas tetracosane (13.39%), (2 E,6 E)-farnesol (7.31%), α-terpineol (8.51%) and caryophyllene oxide (8.05%) were the main components in the fruit oil. Antimicrobial assay revealed that all the essential oils showed moderate to weak inhibition against the tested microorganisms. The leaf oil was the most active and inhibited both S. aureus and E. coli with MIC values of 7.81 μg/mL and 15.6 μg/mL, respectively.
Chemical Analysis and Antioxidant Activity of the Essential Oils of Three Piperaceae Species Growing in the Central Region of Cuba
Authors: Rodríguez Elisa Jorge , Saucedo-Hernández Yanelis , Heyden Yvan Vander , Simó-Alfonso Ernesto F. , Ramis-Ramos Guillermo , Lerma-García María Jesús , Monteagudo Urbano , Bravo Luis , Medinilla Mildred , de Armas Yuriam , Herrero-Martínez José Manuel
Published: March 2019

The present study describes the phytochemical profile and antioxidant activity of the essential oils of three Piperaceae species collected in the central region of Cuba. The essential oils of Piper aduncum, P. auritum and P. umbellatum leaves, obtained by hydrodistillation, were analyzed by gas chromatography-mass spectrometry. The main components of P. aduncum oil were piperitone (34%), camphor (17.1%), camphene (10.9%), 1,8-cineol (8.7%) and viridiflorol (7.4%), whereas that of P. auritum and P. umbellatum was safrole (71.8 and 26.4%, respectively). The antioxidant properties of the essential oils were also evaluated using several assays for radical scavenging ability (DPPH test and reducing power) and inhibition of lipid oxidation (ferric thiocyanate method and evaluation against Cucurbita seed oil by peroxide, thiobarbituric acid and p-anisidine methods). P. auritum showed the strongest antioxidant activity among the Piper species investigated, but lower than those of butylated hydroxyanisol and propyl gallate.
Alkaloids of the South African Amaryllidaceae: A Review
Authors: Nair Jerald J. , Bastida Jaume , Codina Carles , Viladomat Francesc , van Staden Johannes
Published: March 2019

The plant family Amaryllidaceae is known for its horticultural and ornamental appeal as well as its medicinal value. In relation to these characteristics, trade in Amaryllid flower varieties (especially daffodils) is a multi-million dollar revenue generator for the floriculture industry. Of greater significance are the medicinal attributes of the family, which has already spawned the Alzheimer's prescription drug galanthamine, a potent and selective inhibitor of the enzyme acetylcholinesterase, of significance in the progression of neurodegeneration associated with motor neuron diseases, with annual global sales of around $150 million. Furthermore, it is anticipated that an anticancer drug target related to the Amaryllidaceae alkaloid pancratistatin, presently under advanced clinical evaluation, will enter commercial circulation within the next decade. Members of the Amaryllidaceae are distributed through both tropical and subtropical regions of the globe, but are of prominence within three distinct geographical locations, including Andean South America, the Mediterranean basin, and southern Africa. The southern African zone is known to harbor at least a third of the worldwide complement of around 1000 species, many of which are widely utilized in the traditional medicinal practices of the indigenous people of the region. Given its therapeutic and economic value, its natural abundance in the southern African region, coupled to its widespread usage in ethnic medicine, the family Amaryllidaceae provides a diverse and accessible platform for phytochemical based drug discovery. A consolidation of its traditional usage as well as its chemical and pharmacological profiles will thus guide efforts aimed at maximizing this potential. In undertaking this survey of the Amaryllidaceae of southern African, we aimed to achieve these goals.
Guaiol - A Naturally Occurring Insecticidal Sesquiterpene
Authors: Liu Tao , Wang Chun-Juan , Xie Hui-Qin , Mu Qing
Published: March 2019

The dichloromethane fraction of Ferula ferulaeoides was analyzed by GC and GC-MS, and thirty-four compounds were identified. The main component in the fraction, guaiol (37.0%) was separated by chromatographic methods and identified from spectroscopic data, including 1H and 13C NMR, and X-ray crystallographic diffraction. Guaiol showed significant inhibition of aphids at a concentration of 70 mg/L. It also showed good contact activities against the 4th instar larvae of Mythimna separate and 3rd instar larvae of Plutella xylostella, with LD50 values of 0.07 and 8.9 mg/larva, as well as fumigation activity against the 4th instar larvae of M. separata and adult Musca domestica, with LC50 values of 3.5 μL/L and 16.9 μL/L, respectively.
Cembranoids from the Cultured Soft Coral Sinularia Gibberosa
Authors: Lin Hsiu-Fen , Su Huey-Jen , Lee Nai-Lun , Su Jui-Hsin
Published: March 2019

An EtOAc extract of the cultured soft coral Sinularia gibberosa yielded a new cembrane-based diterpenoid, cugibberosene A (1), together with the previously reported three cembranoids (2–4). The structure determination was based on extensive NMR studies. The cytotoxic and antibacterial activities of these isolated metabolites 1–4 were evaluated in vitro.
A New Taraxerol Derivative from the Roots of Microcos Tomentosa
Authors: Kaennakam Sutin , Sichaem Jirapast , Khumkratok Suttira , Siripong Pongpun , Tip-pyang Santi
Published: March 2019

A new 3β- O-vanilloyl-taraxerol, microcisin (1) and eight known compounds, 3β-taraxerol acetate (2), 3β-taraxerol (3), cholest-4-en-3-one (4), cholest-4-en-6β-ol-3-one (5), β-sitosterol (6), 7-hydroxycadalene (7), mellein (8) and vanillin (9), were isolated from the roots of Microcos tomentosa. The structures were determined by extensive analysis of their spectroscopic data. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cells.
Two New Triterpenoids from Gelsemium Elegans and Aglaia odorata
Authors: Liu Bing , Yang Lin , Xu You-Kai , Liao Shang-Gao , Luo Huai-Rong , Na Zhi
Published: March 2019

Eleganoside A (1) and odoratanone A (15), a triterpenoid trisaccharide glycoside and a nortriterpenoid, together with twelve known compounds (2–13) and a mixture of cerebrosides (14) were isolated from Gelsemium elegans and Aglaia odorata. Their structures were elucidated by extensive spectroscopic and spectrometric analysis. Eleganoside A (1) features a 3- O-α-L-rhamnopyranosyl (1→4)-β-D-glucopyranosyl (1→4)-β-D-glucopyranoside of a peculiar 3,16-dihydroxyl-lanosta-8,24-dien-26-oic acid triterpenoid skeleton, and odoratanone A (15) is a 29-norcycloartane-type triterpenoid bearing an unusual five-membered methyl acetal ring. Anti-acetylcholinesterase/butyrylcholinesterase (AChE/BChE) assay indicated that at 50 μM, ethyl caffeate (5) was promising as a dual inhibitor of AChE and BChE, and paeonol (3) and 24-hydroperoxy-24-vinylcholesterol (9) exhibited BChE-selective inhibition.
Inhibition of Tumor Cells Multidrug Resistance by Cucumarioside A2-2, Frondoside A and their Complexes with Cholesterol
Authors: Menchinskaya Ekaterina S. , Aminin Dmitry L. , Avilov Sergey A. , Silchenko Aleksandra S. , Andryjashchenko Pelageya V. , Kalinin Vladimir I. , Stonik Valentin A.
Published: March 2019

In non-cytotoxic concentrations, frondoside A (1) from the sea cucumber Cucumaria okhotensis and cucumarioside A2-2 (2) from C. japonica, as well as their complexes with cholesterol block the activity of membrane transport P-glycoprotein in cells of the ascite form of mouse Ehrlich carcinoma. They prevent in this way an efflux of fluorescent probe Calcein from the cells. Since the blocking of P-glycoprotein activity results in decrease of multidrug resistance, these glycosides and their complexes with cholesterol may be considered as potential inhibitors of multidrug resistance of tumor cells.
Anticholinesterase and Antioxidant Activities of Fucoxanthin Purified from the Microalga Phaeodactylum Tricornutum
Authors: Kawee-ai Arthitaya , Kuntiya Ampin , Kim Sang Moo
Published: March 2019

Hot extraction with acetone was the most efficient method for the extraction of fucoxanthin from Phaeodactylum tricornutum. The purified compound resulted in three main peaks consisted of the trans form along with two isomers. The structure of microalgal fucoxanthin was similar to that of brown seaweed, but the ratio of trans- to cis-form was different. The ratio of the cis-form increased as the extraction temperature increased. Fucoxanthin was unstable at high temperature, in acidic condition, and after long period of storage. Fucoxanthin exhibited strong activity against BChE, with an IC50 value of 1.97 mM and mixed inhibition type, whereas it had weak activity against AChE. The IC50 value on reducing power was 0.01 mM, which was much stronger than those of the positive controls. When the amount of cis-isomer increased by 2%, the scavenging activity against DPPH, hydrogen peroxide, superoxide anion, and reducing power decreased by 21.0, 10.3, 16.0, and 19.7%, respectively. Therefore, fucoxanthin could be a useful approach for Alzheimer's disease treatment.
Novel Decaturin Alkaloids from the Marine-Derived Fungus Penicillium Oxalicum
Authors: Wang Pei-le , Li Dan-yi , Xie Lei-rui , Wu Xin , Hua Hui-ming , Li Zhan-lin
Published: March 2019

From the mycelia of Penicillium oxalicum two new compounds, decaturins E (1) and F (2), have been isolated, along with four known analogues, decaturin A (3), decaturin C (4), decaturin D (5), and oxalicine B (6). The structures were determined by HR-ESI-MS and 1D and 2D NMR analysis.
Flavone C-Glycosides from Lychnis senno and their Antioxidative Activity
Authors: Devkota Hari Prasad , Fukusako Kumiko , Ishiguro Koji , Yahara Shoji
Published: March 2019

A new flavone C-glycoside, 5- O-acetyl-2″-α-rhamnopyranosylisovitexin (1), was isolated from the aerial parts of Lychnis senno Siebold et Zucc. (Family Caryophyllaceae), along with 2″-α-rhamnopyranosylisovitexin (2), 2″-α-rhamnopyranosylisoorientin (3) and isoorientin 3′-mehyl ether (4). All these compounds were isolated for the first time from L. senno and their antioxidative activity was analyzed by the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical-scavenging method. Compound 3 showed moderate antioxidative activity.