Molecules

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Open AccessReview

Potential Antivirals: Natural Products Targeting Replication Enzymes of Dengue and Chikungunya Viruses

by Ana Flávia Costa da Silveira Oliveira, Róbson Ricardo Teixeira, André Silva de Oliveira, Ana Paula Martins de Souza, Milene Lopes da Silva and Sérgio Oliveira de Paula

Molecules 2017, 22(3), 505; https://doi.org/10.3390/molecules22030505 - 22 Mar 2017

Cited by 62 | Viewed by 10450

Abstract

Dengue virus (DENV) and chikungunya virus (CHIKV) are reemergent arboviruses that are transmitted by mosquitoes of the Aedes genus. During the last several decades, these viruses have been responsible for millions of cases of infection and thousands of deaths worldwide. Therefore, several investigations [...] Read more.

Dengue virus (DENV) and chikungunya virus (CHIKV) are reemergent arboviruses that are transmitted by mosquitoes of the Aedes genus. During the last several decades, these viruses have been responsible for millions of cases of infection and thousands of deaths worldwide. Therefore, several investigations were conducted over the past few years to find antiviral compounds for the treatment of DENV and CHIKV infections. One attractive strategy is the screening of compounds that target enzymes involved in the replication of both DENV and CHIKV. In this review, we describe advances in the evaluation of natural products targeting the enzymes involved in the replication of these viruses. Full article

(This article belongs to the Collection Natural Products as Leads or Drugs against Neglected Tropical Diseases)

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2671 KiB

Open AccessArticle

The Anti-Allergic Rhinitis Effect of Traditional Chinese Medicine of Shenqi by Regulating Mast Cell Degranulation and Th1/Th2 Cytokine Balance

by Yang-Yang Shao, Yi-Ming Zhou, Min Hu, Jin-Ze Li, Cheng-Juan Chen, Yong-Jiang Wang, Xiao-Yun Shi, Wen-Jie Wang and Tian-Tai Zhang

Molecules 2017, 22(3), 504; https://doi.org/10.3390/molecules22030504 - 22 Mar 2017

Cited by 46 | Viewed by 7959

Abstract

Shenqi is a traditional Chinese polyherbal medicine has been widely used for the treatment of allergic rhinitis (AR). The aim of this study was to investigate the anti-allergic rhinitis activity of Shenqi and explore its underlying molecular mechanism. Ovalbumin (OVA)-induced allergic rhinitis rat [...] Read more.

Shenqi is a traditional Chinese polyherbal medicine has been widely used for the treatment of allergic rhinitis (AR). The aim of this study was to investigate the anti-allergic rhinitis activity of Shenqi and explore its underlying molecular mechanism. Ovalbumin (OVA)-induced allergic rhinitis rat model was used to evaluate the anti-allergic rhinitis effect of Shenqi. The effect of Shenqi on IgE-mediated degranulation was measured using rat basophilic leukemia (RBL-2H3) cells. Primary spleen lymphocytes were isolated to investigate the anti-allergic mechanism of Shenqi by detecting the expression of transcription factors via Western blot and the level of cytokines (IL-4 and IFN-γ) via ELISA. In OVA-induced AR rat models, Shenqi relieved the allergic rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and reduced the levels of IL-4 and IgE. The results from the in vitro study certified that Shenqi inhibited mast cell degranulation. Furthermore, the results of GATA3, T-bet, p-STAT6, and SOCS1 expression and production of IFN-γ and IL-4 demonstrated that Shenqi balanced the ratio of Th1/Th2 (IFN-γ/IL-4) in OVA-stimulated spleen lymphocytes. In conclusion, these results suggest that Shenqi exhibits an obvious anti-allergic effect by suppressing the mast cell-mediated allergic response and by improving the imbalance of Th1/Th2 ratio in allergic rhinitis. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Consecutive One-Pot versus Domino Multicomponent Approaches to 3-(Diarylmethylene)oxindoles

by Sunhwa Park, Jiyun Lee, Kye Jung Shin, Euichaul Oh and Jae Hong Seo

Molecules 2017, 22(3), 503; https://doi.org/10.3390/molecules22030503 - 22 Mar 2017

Cited by 13 | Viewed by 5273

Abstract

Based on consecutive one-pot conditions combining three palladium-catalyzed reactions (Sonogashira, Heck and Suzuki-Miyaura reactions), a more efficient domino multicomponent method has been successfully developed to access a wide variety of 3-(diarylmethylene)oxindoles. Microwave irradiation and use of a silver salt were the most important [...] Read more.

Based on consecutive one-pot conditions combining three palladium-catalyzed reactions (Sonogashira, Heck and Suzuki-Miyaura reactions), a more efficient domino multicomponent method has been successfully developed to access a wide variety of 3-(diarylmethylene)oxindoles. Microwave irradiation and use of a silver salt were the most important factors to achieve high yields and stereoselectivity. Full article

(This article belongs to the Collection Heterocyclic Compounds)

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Graphical abstract

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Open AccessArticle

Carapanosins A–C from Seeds of Andiroba (Carapa guianensis, Meliaceae) and Their Effects on LPS-Activated NO Production

by Keiichiro Higuchi, Teppei Miyake, Shoko Ohmori, Yoshimi Tani, Katsuhiko Minoura, Takashi Kikuchi, Takeshi Yamada and Reiko Tanaka

Molecules 2017, 22(3), 502; https://doi.org/10.3390/molecules22030502 - 22 Mar 2017

Cited by 12 | Viewed by 4684

Abstract

Two new phragmalin-type limonoids, Carapanosins A and B (1 and 2), and a new gedunin-type limonoid, Carapansin C (3), together with five known limonoids (4–8) were isolated from the oil of Carapa guianensis A_UBLET [...] Read more.

Two new phragmalin-type limonoids, Carapanosins A and B (1 and 2), and a new gedunin-type limonoid, Carapansin C (3), together with five known limonoids (4–8) were isolated from the oil of Carapa guianensis A_UBLET (Meliaceae) seeds, a traditional medicine in Brazil and Latin American countries. Their structures were elucidated on the basis of spectroscopic analyses using 1D and 2D NMR techniques and HRFABMS. Compounds 1–8 were evaluated for their effects on the production of NO in LPS-activated mouse peritoneal macrophages. The NO inhibitory assay suggested that Compounds 3, 6, and 8 may be valuable as potential inhibitors of macrophage activation. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Synthesis, Characterization, and the Antioxidant Activity of Double Quaternized Chitosan Derivatives

by Lijie Wei, Qing Li, Wenqiang Tan, Fang Dong, Fang Luan and Zhanyong Guo

Molecules 2017, 22(3), 501; https://doi.org/10.3390/molecules22030501 - 22 Mar 2017

Cited by 37 | Viewed by 5891

Abstract

With the specialty of improving the water solubility of chitosan, quaternary ammonium salts have broadened the application of this polysaccharide in food, medicine and pesticides. To identify the effect of quaternary ammonium salts’ quantity, single quaternized chitosan N-phenmethyl-N,N-dimethyl [...] Read more.

With the specialty of improving the water solubility of chitosan, quaternary ammonium salts have broadened the application of this polysaccharide in food, medicine and pesticides. To identify the effect of quaternary ammonium salts’ quantity, single quaternized chitosan N-phenmethyl-N,N-dimethyl chitosan (PDCS), double quaternized chitosan N-(1-pyridylmethyl-2-ylmethyl)-N,N-dimethyl chitosan (MP2MDCS), N-(1-pyridylmethyl-3-ylmethyl)-N,N-dimethyl chitosan (MP3MDCS), and N-(1-pyridylmethyl-4-ylmethyl)-N,N-dimethyl chitosan (MP4MDCS) were designed and synthesized successfully through chemical modification of chitosan. Besides, three kinds of antioxidant activities, including hydroxyl radicals, superoxide radicals, and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radicals were tested in vitro. As shown in this paper, the scavenging ability was ranking in order of MP3MDC > MP4MDCS > MP2MDCS > PDCS > chitosan at 1.6 mg/mL in all assays. All double quaternary ammonium salts were better than chitosan or the single quaternary ammonium salt. In addition, MP3MDCS could scavenge hydroxyl radicals totally at 1.6 mg/mL. MP2MDCS and MP4MDCS with more than 90% scavenging indices both had great scavenging ability on hydroxyl radicals or DPPH radicals. Furthermore, these data demonstrated that the increasing number of the positive charge would improve the antioxidant property of chitosan derivatives, and the N-pyridinium position would influence the scavenging radical ability. Full article

(This article belongs to the Section Medicinal Chemistry)

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Open AccessArticle

Physicochemical Properties and Microbial Quality of Tremella aurantialba Packed in Antimicrobial Composite Films

by Jian Fan, Zhuangzhuang Chu, Lin Li, Tianrui Zhao, Min Yin and Yuyue Qin

Molecules 2017, 22(3), 500; https://doi.org/10.3390/molecules22030500 - 22 Mar 2017

Cited by 7 | Viewed by 5212

Abstract

The effects of poly(lactic acid) (PLA)-based film with inorganic antimicrobial nano-TiO₂ and nano-Ag on the physicochemical and microbial quality of Tremella aurantialba stored at 4 ± 1 °C for 16 days was investigated. Rosemary essential oil (REO, 9 wt %) was added [...] Read more.

The effects of poly(lactic acid) (PLA)-based film with inorganic antimicrobial nano-TiO₂ and nano-Ag on the physicochemical and microbial quality of Tremella aurantialba stored at 4 ± 1 °C for 16 days was investigated. Rosemary essential oil (REO, 9 wt %) was added into PLA film as plasticizer. Low-density polyethylene (LDPE) and PLA film was used as the controls. The experiment measured physicochemical properties and microbial levels, such as weight loss, firmness, vitamin C, color, microbiological quality, and sensory quality. Although Tremella aurantialba packed by nano-composite films had the highest weight loss (4.96% and 5.17%) at the end of storage, it was still in the vicinity of 5%. Tremella aurantialba packed with nano-composite films were significantly (p < 0.05) firmer than those packed by LDPE, PLA, and PLA/REO films. The nano-composite films were more effective in reducing vitamin C and microbial counts and preserving the color of Tremella aurantialba than the other three groups. The overall acceptability of Tremella aurantialba packed by the nano-composite films still remained good and within the limits of marketability after 12 days of storage. The results suggested that the proposed nano-composite films could maintain the quality of Tremella aurantialba and extend its postharvest life. Full article

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Open AccessArticle

Exploring the Antitumor Mechanism of High-Dose Cytarabine through the Metabolic Perturbations of Ribonucleotide and Deoxyribonucleotide in Human Promyelocytic Leukemia HL-60 Cells

by Zheng Li, Jian-Ru Guo, Qian-Qian Chen, Cai-Yun Wang, Wei-Jia Zhang, Mei-Cun Yao and Wei Zhang

Molecules 2017, 22(3), 499; https://doi.org/10.3390/molecules22030499 - 21 Mar 2017

Cited by 29 | Viewed by 11513

Abstract

Despite the apparent clinical benefits of high-dose cytarabine (Ara-C) over lower dose Ara-C in acute myeloid leukemia (AML) therapy, the mechanism behind high-dose Ara-C therapy remains uncertain. In this study, a LC-MS-based method was carried out to investigate the metabolic alteration of ribonucleotide [...] Read more.

Despite the apparent clinical benefits of high-dose cytarabine (Ara-C) over lower dose Ara-C in acute myeloid leukemia (AML) therapy, the mechanism behind high-dose Ara-C therapy remains uncertain. In this study, a LC-MS-based method was carried out to investigate the metabolic alteration of ribonucleotide and deoxyribonucleotide in human promyelocytic leukemia cells (HL-60) after treatment with Ara-C to reveal its antitumor mechanism. The metabolic results revealed that four nucleotides (ATP, ADP, CDP, and dCTP) could be used as potential biomarkers indicating the benefit of high-dose Ara-C over lower dose Ara-C treatment. Combining metabolic perturbation and cell cycle analysis, we conjectured that, apart from the acknowledged mechanism of Ara-C on tumor inhibition, high-dose Ara-C could present a specific action pathway. It was suggested that the pronounced rise in AMP/ATP ratio induced by high-dose Ara-C can trigger AMP-activated protein kinase (AMPK) and subsequently Forkhead Box, class O (FoxO), to promote cell cycle arrest. Moreover, the significant decrease in CDP pool induced by high-dose Ara-C might further accelerate the reduction of dCTP, which then aggravates DNA synthesis disturbance. As a result, all of these alterations led to heightened tumor inhibition. This study provides new insight in the investigation of potential mechanisms in the clinical benefits of high-dose Ara-C in therapy for AML. Full article

(This article belongs to the Special Issue Nucleoside and Nucleotide Analogues)

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Open AccessArticle

The Effects of Sweet Foods on the Pharmacokinetics of Glycyrrhizic Acid by icELISA

by Bingqian Jiang, Huihua Qu, Hui Kong, Yue Zhang, Shuchen Liu, Jinjun Cheng, Xin Yan and Yan Zhao

Molecules 2017, 22(3), 498; https://doi.org/10.3390/molecules22030498 - 21 Mar 2017

Cited by 7 | Viewed by 4343

Abstract

The effect of sweet foods, such as honey, was investigated from the perspective of pharmacokinetics on the absorption of glycyrrhizic acid (GA). Due to the unique properties of indirect competitive enzyme-linked immunosorbent assay (icELISA), namely, its: specificity, sensitivity, repeatability, simple pretreatment of samples, [...] Read more.

The effect of sweet foods, such as honey, was investigated from the perspective of pharmacokinetics on the absorption of glycyrrhizic acid (GA). Due to the unique properties of indirect competitive enzyme-linked immunosorbent assay (icELISA), namely, its: specificity, sensitivity, repeatability, simple pretreatment of samples, fast and simple operation, and because it is economic and non-polluting, it has received increased attention. In this study, we used the advantages of this method to see how honey affected the pharmacokinetics of GA. The effects of honey on the pharmacokinetics of GA by ELISA were investigated for the first time. The results indicate that honey can postpone the peak concentration of GA in mouse blood, and this effect correlates well with fructose. As a representative of sweet foods, the result provides the valuable information that honey, or fructose, may act as sustained-releasing drugs in clinical scenarios; and that sweet foods may have some influences on drugs when taken together. Full article

(This article belongs to the Special Issue New Methodologies in Natural Product Analytics and Structure Elucidation)

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Open AccessArticle

Biosynthesis of Oligomeric Anthocyanins from Grape Skin Extracts

by Jin-Woo Hwang, Sithranga Boopathy Natarajan, Yon-Suk Kim, Eun-Kyung Kim, Jae Woong Lee, Sang-Ho Moon, Byong-Tae Jeon and Pyo-Jam Park

Molecules 2017, 22(3), 497; https://doi.org/10.3390/molecules22030497 - 21 Mar 2017

Cited by 8 | Viewed by 6154

Abstract

We synthesized oligomeric anthocyanins from grape skin-derived monomeric anthocyanins such as anthocyanidin and proanthocyanidin by a fermentation technique using Aspergillus niger, crude enzymes and glucosidase. The biosyntheses of the oligomeric anthocyanins carried out by the conventional method using Aspergillus niger and crude [...] Read more.

We synthesized oligomeric anthocyanins from grape skin-derived monomeric anthocyanins such as anthocyanidin and proanthocyanidin by a fermentation technique using Aspergillus niger, crude enzymes and glucosidase. The biosyntheses of the oligomeric anthocyanins carried out by the conventional method using Aspergillus niger and crude enzymes were confirmed by ESI-MS. The molecular weight of the synthesized anthocyanin oligomers was determined using MALDI-MS. The yield of anthocyanin oligomers using crude enzymes was higher than that of the synthesis using Aspergillus fermentation. Several studies have been demonstrated that oligomeric anthocyanins have higher antioxidant activity than monomeric anthocyanins. Fermentation-based synthesis of oligomeric anthocyanins is an alternative way of producing useful anthocyanins that could support the food industry. Full article

(This article belongs to the Special Issue Green Production of Bioactive Natural Products)

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Open AccessArticle

GC-MS Metabolomic Analysis to Reveal the Metabolites and Biological Pathways Involved in the Developmental Stages and Tissue Response of Panax ginseng

by Jia Liu, Yang Liu, Yu Wang, Ann Abozeid, Yuan-Gang Zu, Xiao-Ning Zhang and Zhong-Hua Tang

Molecules 2017, 22(3), 496; https://doi.org/10.3390/molecules22030496 - 21 Mar 2017

Cited by 33 | Viewed by 7044

Abstract

Ginsenosides, the major compounds present in ginseng, are known to have numerous physiological and pharmacological effects. The physiological processes, enzymes and genes involved in ginsenoside synthesis in P. ginseng have been well characterized. However, relatively little information is known about the dynamic metabolic [...] Read more.

Ginsenosides, the major compounds present in ginseng, are known to have numerous physiological and pharmacological effects. The physiological processes, enzymes and genes involved in ginsenoside synthesis in P. ginseng have been well characterized. However, relatively little information is known about the dynamic metabolic changes that occur during ginsenoside accumulation in ginseng. To explore this topic, we isolated metabolites from different tissues at different growth stages, and identified and characterized them by using gas chromatography coupled with mass spectrometry (GC-MS). The results showed that a total of 30, 16, 20, 36 and 31 metabolites were identified and involved in different developmental stages in leaf, stem, petiole, lateral root and main root, respectively. To investigate the contribution of tissue to the biosynthesis of ginsenosides, we examined the metabolic changes of leaf, stem, petiole, lateral root and main root during five development stages: 1-, 2-, 3-, 4- and 5-years. The score plots of partial least squares-discriminate analysis (PLS-DA) showed clear discrimination between growth stages and tissue samples. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis in the same tissue at different growth stages indicated profound biochemical changes in several pathways, including carbohydrate metabolism and pentose phosphate metabolism, in addition, the tissues displayed significant variations in amino acid metabolism, sugar metabolism and energy metabolism. These results should facilitate further dissection of the metabolic flux regulation of ginsenoside accumulation in different developmental stages or different tissues of ginseng. Full article

(This article belongs to the Special Issue New Methodologies in Natural Product Analytics and Structure Elucidation)

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Open AccessArticle

3-Substituted N-Benzylpyrazine-2-carboxamide Derivatives: Synthesis, Antimycobacterial and Antibacterial Evaluation

by Lucia Semelková, Ondřej Janďourek, Klára Konečná, Pavla Paterová, Lucie Navrátilová, František Trejtnar, Vladimír Kubíček, Jiří Kuneš, Martin Doležal and Jan Zitko

Molecules 2017, 22(3), 495; https://doi.org/10.3390/molecules22030495 - 21 Mar 2017

Cited by 9 | Viewed by 4422

Abstract

A series of substituted N-benzyl-3-chloropyrazine-2-carboxamides were prepared as positional isomers of 5-chloro and 6-chloro derivatives, prepared previously. During the aminolysis of the acyl chloride, the simultaneous substitution of chlorine with benzylamino moiety gave rise to N-benzyl-3-(benzylamino)pyrazine-2-carboxamides as side products, in some [...] Read more.

A series of substituted N-benzyl-3-chloropyrazine-2-carboxamides were prepared as positional isomers of 5-chloro and 6-chloro derivatives, prepared previously. During the aminolysis of the acyl chloride, the simultaneous substitution of chlorine with benzylamino moiety gave rise to N-benzyl-3-(benzylamino)pyrazine-2-carboxamides as side products, in some cases. Although not initially planned, the reaction conditions were modified to populate this double substituted series. The final compounds were tested against four mycobacterial strains. N-(2-methylbenzyl)-3-((2-methylbenzyl)amino)pyrazine-2-carboxamide (1a) and N-(3,4-dichlorobenzyl)-3-((3,4-dichlorobenzyl)amino)pyrazine-2-carboxamide (9a) proved to be the most effective against Mycobacterium tuberculosis H37Rv, with MIC = 12.5 μg·mL⁻¹. Compounds were screened for antibacterial activity. The most active compound was 3-chloro-N-(2-chlorobenzyl)pyrazine-2-carboxamide (5) against Staphylococcus aureus with MIC = 7.81 μM, and Staphylococcus epidermidis with MIC = 15.62 μM. HepG2 in vitro cytotoxicity was evaluated for the most active compounds; however, no significant toxicity was detected. Compound 9a was docked to several conformations of the enoyl-ACP-reductase of Mycobacterium tuberculosis. In some cases, it was capable of H-bond interactions, typical for most of the known inhibitors. Full article

(This article belongs to the Section Medicinal Chemistry)

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Open AccessArticle

Profiling and Preparation of Metabolites from Pyragrel in Human Urine by Online Solid-Phase Extraction Coupled with High Performance Liquid Chromatography Tandem Mass Spectrometry Followed by a Macroporous Resin-Based Purification Approach

by Xin Zhao, Jingjing Jiang, Guang Yang, Jie Huang, Guoping Yang, Guangwei He, Zhaoxing Chu, Taijun Hang and Guorong Fan

Molecules 2017, 22(3), 494; https://doi.org/10.3390/molecules22030494 - 21 Mar 2017

Cited by 7 | Viewed by 5656

Abstract

Pyragrel, a new anticoagulant drug, is derived from the molecular combination of ligustrazine and ferulic acid. Pyragrel showed significant inhibitory activity against platelet aggregation induced by adenosine diphosphate (ADP), and had been approved for a phase I clinical trial by CFDA. To characterize [...] Read more.

Pyragrel, a new anticoagulant drug, is derived from the molecular combination of ligustrazine and ferulic acid. Pyragrel showed significant inhibitory activity against platelet aggregation induced by adenosine diphosphate (ADP), and had been approved for a phase I clinical trial by CFDA. To characterize the metabolites of Pyragrel in human urine after intravenous administration, a reliable online solid-phase extraction couple with high performance liquid chromatography tandem mass spectrometry (online SPE-HPLC-MSⁿ) method was conceived and applied. Five metabolites were detected and tentatively identified, which suggested that the major metabolic pathways of Pyragrel in human were double-bond reduction, double-bond oxidation, and then followed by glucuronide conjugation. Two main metabolites were then prepared using β-glucuronide hydrolysis and macroporous resin purification approach followed by preparative high-performance liquid chromatography (PHPLC) method, with their structures confirmed on the basis of nuclear magnetic resonance (NMR) data. This study provided information for the further study of the metabolism and excretion of Pyragrel. Full article

(This article belongs to the Section Metabolites)

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Open AccessArticle

Nonradiative Relaxation Mechanisms of UV Excited Phenylalanine Residues: A Comparative Computational Study

by Momir Mališ and Nađa Došlić

Molecules 2017, 22(3), 493; https://doi.org/10.3390/molecules22030493 - 21 Mar 2017

Cited by 8 | Viewed by 5292

Abstract

The present work is directed toward understanding the mechanisms of excited state deactivation in three neutral model peptides containing the phenylalanine residue. The excited state dynamics of the

γ_{L} (g +)

folded form of N-acetylphenylalaninylamide (NAPA B) and its [...] Read more.

The present work is directed toward understanding the mechanisms of excited state deactivation in three neutral model peptides containing the phenylalanine residue. The excited state dynamics of the

γ_{L} (g +)

folded form of N-acetylphenylalaninylamide (NAPA B) and its amide-N-methylated derivative (NAPMA B) is reviewed and compared to the dynamics of the monohydrated structure of NAPA (NAPAH). The goal is to unravel how the environment, and in particular solvation, impacts the photodynamics of peptides. The systems are investigated using reaction path calculations and surface hopping nonadiabatic dynamics based on the coupled cluster doubles (CC2) method and time-dependent density functional theory. The work emphasizes the role that excitation transfer from the phenyl

π π^{*}

to amide

n π^{*}

state plays in the deactivation of the three systems and shows how the ease of out-of-plane distortions of the amide group determines the rate of population transfer between the two electronic states. The subsequent dynamics on the

n π^{*}

state is barrierless along several pathways and leads to fast deactivation to the ground electronic state. Full article

(This article belongs to the Special Issue Experimental and Computational Photochemistry of Bioorganic Molecules)

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Open AccessArticle

New Chiral Ebselen Analogues with Antioxidant and Cytotoxic Potential

by Agata J. Pacuła, Katarzyna B. Kaczor, Jędrzej Antosiewicz, Anna Janecka, Angelika Długosz, Tomasz Janecki, Andrzej Wojtczak and Jacek Ścianowski

Molecules 2017, 22(3), 492; https://doi.org/10.3390/molecules22030492 - 20 Mar 2017

Cited by 41 | Viewed by 7521

Abstract

New chiral camphane-derived benzisoselenazol-3(2H)-ones and corresponding diselenides have been synthetized using a convenient one-pot procedure. Se-N bond was efficiently converted to an Se-Se bond, which could also be easily re-oxidized to the initial benzisoselenazolone moiety. The antioxidant activity of camphor derivatives [...] Read more.

New chiral camphane-derived benzisoselenazol-3(2H)-ones and corresponding diselenides have been synthetized using a convenient one-pot procedure. Se-N bond was efficiently converted to an Se-Se bond, which could also be easily re-oxidized to the initial benzisoselenazolone moiety. The antioxidant activity of camphor derivatives was evaluated and compared to the reactivity of a series of N-amino acid benzisoselenazol-3(2H)-ones obtained by a modified procedure involving the improved synthesis and isolation of the diseleno bis(dibenzoic) acid. The most efficient peroxide scavengers, N-bornyl and N-leucine methyl ester benzisoselenazol-3(2H)-ones, were further evaluated as cytotoxic agents on four cancer cell lines (MCF-7, HEP G2, HL 6, and DU 145) and normal cell line PNT1A. The highest antiproliferative potential was evaluated for two compounds bearing a 3-methylbutyl carbon chain, N-leucine methyl ester and N-3-methylbutyl benzisoselenazol-3(2H)-ones. Full article

(This article belongs to the Special Issue Celebrating Two Centuries of Research in Selenium Chemistry: State of the Art and New Prospectives)

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Open AccessArticle

[2 + 2] Photodimerization of Naphthylvinylpyridines through Cation-π Interactions in Acidic Solution

by Shinji Yamada and Yuka Nojiri

Molecules 2017, 22(3), 491; https://doi.org/10.3390/molecules22030491 - 20 Mar 2017

Cited by 12 | Viewed by 4816

Abstract

Irradiation of (E)-4-(2-(2-naphthyl)vinyl)pyridine (1a) and (E)-4-(2-(1-naphthyl)vinyl)pyridine (1b) with a 250 W high-pressure mercury lamp in acidic solution afforded synHT dimers in high stereoselectivities. Similar results were obtained by visible light irradiation. On the other [...] Read more.

Irradiation of (E)-4-(2-(2-naphthyl)vinyl)pyridine (1a) and (E)-4-(2-(1-naphthyl)vinyl)pyridine (1b) with a 250 W high-pressure mercury lamp in acidic solution afforded synHT dimers in high stereoselectivities. Similar results were obtained by visible light irradiation. On the other hand, when the reactions were carried out under neutral conditions, the stereoselectivities were very low, and the yields were decreased by visible light irradiation. Comparison of the UV-vis spectra between the acidic and the neutral conditions elucidated that the red shift was observed in acidic solutions. These results show that HCl plays essential roles not only in the preorientation of substrates through cation-π interactions, but also in the changes in the absorption properties of substrates that enable visible light reactions. Full article

(This article belongs to the Special Issue Cutting-Edge Organic Chemistry in Japan)

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Open AccessReview

Pretreatment of Lignocellulosic Biomass with Ionic Liquids and Ionic Liquid-Based Solvent Systems

by Qidong Hou, Meiting Ju, Weizun Li, Le Liu, Yu Chen and Qian Yang

Molecules 2017, 22(3), 490; https://doi.org/10.3390/molecules22030490 - 20 Mar 2017

Cited by 132 | Viewed by 13162

Abstract

Pretreatment is very important for the efficient production of value-added products from lignocellulosic biomass. However, traditional pretreatment methods have several disadvantages, including low efficiency and high pollution. This article gives an overview on the applications of ionic liquids (ILs) and IL-based solvent systems [...] Read more.

Pretreatment is very important for the efficient production of value-added products from lignocellulosic biomass. However, traditional pretreatment methods have several disadvantages, including low efficiency and high pollution. This article gives an overview on the applications of ionic liquids (ILs) and IL-based solvent systems in the pretreatment of lignocellulosic biomass. It is divided into three parts: the first deals with the dissolution of biomass in ILs and IL-based solvent systems; the second focuses on the fractionation of biomass using ILs and IL-based solvent systems as solvents; the third emphasizes the enzymatic saccharification of biomass after pretreatment with ILs and IL-based solvent systems. Full article

(This article belongs to the Special Issue Ionic Liquids and Deep Eutectic Solvents for Synthesis, Materials and Energy)

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Open AccessArticle

Effects of Momordica charantia (Bitter Melon) on Ischemic Diabetic Myocardium

by Attila Czompa, Alexandra Gyongyosi, Kitti Szoke, Istvan Bak, Evelin Csepanyi, David D. Haines, Arpad Tosaki and Istvan Lekli

Molecules 2017, 22(3), 488; https://doi.org/10.3390/molecules22030488 - 20 Mar 2017

Cited by 14 | Viewed by 6844

Abstract

Objective: A rat model is here used to test a hypothesis that Momordica charantia (Bitter melon (BM)) extract favorably alters processes in cardiovascular tissue and is systemically relevant to the pathophysiology of type 2 diabetes (T2DM) and related cardiovascular disease. Methods: [...] Read more.

Objective: A rat model is here used to test a hypothesis that Momordica charantia (Bitter melon (BM)) extract favorably alters processes in cardiovascular tissue and is systemically relevant to the pathophysiology of type 2 diabetes (T2DM) and related cardiovascular disease. Methods: Male Lean and Zucker Obese (ZO) rats were gavage-treated for six weeks with 400 mg/kg body weight bitter melon (BM) extract suspended in mucin–water vehicle, or with vehicle (Control). Animals were segregated into four treatment groups, 10 animals in each group, according to strain (Lean or ZO) and treatment (Control or BM). Following six-week treatment periods, peripheral blood was collected from selected animals, followed by sacrifice, thoracotomy and mounting of isolated working heart setup. Results: Body mass of both Lean and ZO rats was unaffected by treatment, likewise, peripheral blood fasting glucose levels showed no significant treatment-related effects. However, some BM treatment-related improvement was noted in postischemic cardiac functions when Lean, BM-treated animals were compared to vehicle treated Lean control rats. Treatment of Lean, but not ZO, rats significantly reduced the magnitude of infarcted zone in isolated hearts subjected to 30 min of ischemia followed by 2 h of working mode reperfusion. Immunohistochemical demonstration of caspase-3 expression by isolated heart tissues subjected to 30 min of ischemia followed by 2 h of reperfusion, revealed significant correlation between BM treatment and reduced expression of this enzyme in hearts obtained from both Lean and ZO animals. The hierarchy and order of caspase-3 expression from highest to lowest was as follows: ZO rats receiving vehicle > ZO rats receiving BM extract > Lean rats treated receiving vehicle > Lean rats administered BM extract. Outcomes of analyses of peripheral blood content of cardiac-related analytics: with particular relevance to clinical application was a significant elevation in blood of ZO and ZO BM-treated, versus Lean rats of total cholesterol (high density lipoprotein HDL-c + low density lipoprotein LDL-c), with an inferred increase in HDL-c/LDL-c ratio—an outcome associated with decreased risk of atherosclerotic disease. Conclusions: BM extract failed to positively affect T2DM- and cardiovascular-related outcomes at a level suggesting use as a standalone treatment. Nevertheless, the encouraging effects of BM in enhancement of cardiac function, suppression of post-ischemic/reperfused infarct size extent and capacity to modulate serum cholesterol, will likely make it useful as an adjuvant therapy for the management of T2DM and related cardiovascular diseases. Full article

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Open AccessCommunication

Separation of Alkyne Enantiomers by Chiral Column HPLC Analysis of Their Cobalt-Complexes

by Qiaoyun Liu, Jing Wang, Junfei Li, Xiaolei Wang, Shichao Lu, Xuan Li, Yaling Gong and Shu Xu

Molecules 2017, 22(3), 466; https://doi.org/10.3390/molecules22030466 - 20 Mar 2017

Viewed by 5153

Abstract

Separation of the enantiomers of new chiral alkynes in strategic syntheses and bioorthogonal studies is always problematic. The chiral column high-performance liquid chromatography (HPLC) method in general could not be directly used to resolve such substrates, since the differentiation of the alkyne segment [...] Read more.

Separation of the enantiomers of new chiral alkynes in strategic syntheses and bioorthogonal studies is always problematic. The chiral column high-performance liquid chromatography (HPLC) method in general could not be directly used to resolve such substrates, since the differentiation of the alkyne segment with the other alkane/alkene segment is not significant in the stationary phase, and the alkyne group is not a good UV chromophore. Usually, a pre-column derivatization reaction with a tedious workup procedure is needed. Making use of easily-prepared stable alkyne-cobalt-complexes, we developed a simple and general method by analyzing the in situ generated cobalt-complex of chiral alkynes using chiral column HPLC. This new method is especially suitable for the alkynes without chromophores and other derivable groups. Full article

(This article belongs to the Section Organometallic Chemistry)

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Open AccessArticle

Ginsenoside PPD’s Antitumor Effect via Down-Regulation of mTOR Revealed by Super-Resolution Imaging

by Bo Teng, Junguang Jiang, Lijing Zhao, Jing Gao, Junyu Chen, Zhe Liu, Hongda Wang and Binfeng Lu

Molecules 2017, 22(3), 486; https://doi.org/10.3390/molecules22030486 - 19 Mar 2017

Cited by 14 | Viewed by 5996

Abstract

Derived from Panax ginseng, the natural product 20(S)-Protopanaxadiol (PPD) has been reported for its cytotoxicity against several cancer cell lines. The molecular mechanism is, however, not well understood. Here we show that PPD significantly inhibits proliferation, induces apoptosis and causes [...] Read more.

Derived from Panax ginseng, the natural product 20(S)-Protopanaxadiol (PPD) has been reported for its cytotoxicity against several cancer cell lines. The molecular mechanism is, however, not well understood. Here we show that PPD significantly inhibits proliferation, induces apoptosis and causes G2/M cell cycle arrest in human laryngeal carcinoma cells (Hep-2 cells). PPD also decreases the levels of proteins related to cell proliferation. Moreover, PPD-induced apoptosis is characterized by a dose-dependent down-regulation of Bcl-2 expression and up-regulation of Bax, and is accompanied by the activation of Caspase-3 as well. Further molecular mechanism is revealed by direct stochastic optical reconstruction microscopy (dSTORM)—a novel high-precision localization microscopy which enables effective resolution down to the order of 10 nm. It shows the expression and spatial arrangement of mTOR and its downstream effectors, demonstrating that this ginsenoside exerts its excellent anticancer effects via down-regulation of mTOR signaling pathway in Hep-2 cells. Taken together, our findings elucidate that the antitumor effect of PPD is associated with its regulation of mTOR expression and distribution, which encourages further studies of PPD as a promising therapeutic agent against laryngeal carcinoma. Full article

(This article belongs to the Special Issue Current Trends in Ginseng Research)

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Open AccessArticle

Synthesis of Randomly Substituted Anionic Cyclodextrins in Ball Milling

by László Jicsinszky, Marina Caporaso, Emanuela Calcio Gaudino, Cristina Giovannoli and Giancarlo Cravotto

Molecules 2017, 22(3), 485; https://doi.org/10.3390/molecules22030485 - 19 Mar 2017

Cited by 13 | Viewed by 5218

Abstract

A number of influencing factors mean that the random substitution of cyclodextrins (CD) in solution is difficult to reproduce. Reaction assembly in mechanochemistry reduces the number of these factors. However, lack of water can improve the reaction outcomes by minimizing the reagent’s hydrolysis. [...] Read more.

A number of influencing factors mean that the random substitution of cyclodextrins (CD) in solution is difficult to reproduce. Reaction assembly in mechanochemistry reduces the number of these factors. However, lack of water can improve the reaction outcomes by minimizing the reagent’s hydrolysis. High-energy ball milling is an efficient, green and simple method for one-step reactions and usually reduces degradation and byproduct formation. Anionic CD derivatives have successfully been synthesized in the solid state, using a planetary ball mill. Comparison with solution reactions, the solvent-free conditions strongly reduced the reagent hydrolysis and resulted in products of higher degree of substitution (DS) with more homogeneous DS distribution. The synthesis of anionic CD derivatives can be effectively performed under mechanochemical activation without significant changes to the substitution pattern but the DS distributions were considerably different from the products of solution syntheses. Full article

(This article belongs to the Special Issue Cyclodextrin Chemistry)

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4122 KiB

Open AccessReview

Catechins and Their Therapeutic Benefits to Inflammatory Bowel Disease

by Fei-Yan Fan, Li-Xuan Sang and Min Jiang

Molecules 2017, 22(3), 484; https://doi.org/10.3390/molecules22030484 - 19 Mar 2017

Cited by 244 | Viewed by 15242

Abstract

Catechins are natural polyphenolic phytochemicals that exist in food and medicinal plants, such as tea, legume and rubiaceae. An increasing number of studies have associated the intake of catechins-rich foods with the prevention and treatment of chronic diseases in humans, such as inflammatory [...] Read more.

Catechins are natural polyphenolic phytochemicals that exist in food and medicinal plants, such as tea, legume and rubiaceae. An increasing number of studies have associated the intake of catechins-rich foods with the prevention and treatment of chronic diseases in humans, such as inflammatory bowel disease (IBD). Some studies have demonstrated that catechins could significantly inhibit the excessive oxidative stress through direct or indirect antioxidant effects and promote the activation of the antioxidative substances such as glutathione peroxidases (GPO) and glutathione (GSH), reducing the oxidative damages to the colon. In addition, catechins can also regulate the infiltration and proliferation of immune related-cells, such as neutrophils, colonic epithelial cells, macrophages, and T lymphocytes, helping reduce the inflammatory relations and provide benefits to IBD. Perhaps catechins can further inhibit the deterioration of intestinal lesions through regulating the cell gap junctions. Furthermore, catechins can exert their significant anti-inflammatory properties by regulating the activation or deactivation of inflammation-related oxidative stress-related cell signaling pathways, such as nuclear factor-kappa B (NF-κB), mitogen activated protein kinases (MAPKs), transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2), signal transducer and the activator of transcription 1/3 (STAT1/3) pathways. Finally, catechins can also stabilize the structure of the gastrointestinal micro-ecological environment via promoting the proliferation of beneficial intestinal bacteria and regulating the balance of intestinal flora, so as to relieve the IBD. Furthermore, catechins may regulate the tight junctions (TJ) in the epithelium. This paper elaborates the currently known possible molecular mechanisms of catechins in favor of IBD. Full article

(This article belongs to the Special Issue Catechins and Human Health: Current State of the Science)

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817 KiB

Open AccessFeature PaperReview

Synthesis of Substituted α-Trifluoromethyl Piperidinic Derivatives

by Sarah Rioton, Domingo Gomez Pardo and Janine Cossy

Molecules 2017, 22(3), 483; https://doi.org/10.3390/molecules22030483 - 19 Mar 2017

Cited by 8 | Viewed by 7227

Abstract

A comprehensive survey of pathways leading to the generation of α-trifluoromethyl monocyclic piperidinic derivatives is provided (65 references). These compounds have been synthesized either from 6-membered rings e.g., pipecolic acid or lactam derivatives by introduction a trifluoromethyl group, from pyridine or pyridinone derivatives [...] Read more.

A comprehensive survey of pathways leading to the generation of α-trifluoromethyl monocyclic piperidinic derivatives is provided (65 references). These compounds have been synthesized either from 6-membered rings e.g., pipecolic acid or lactam derivatives by introduction a trifluoromethyl group, from pyridine or pyridinone derivatives by reduction, and from 5-membered rings e.g., prolinol derivatives by ring expansion, from linear amines by cyclization or from dienes/dienophiles by [4 + 2]-cycloaddition. Full article

(This article belongs to the Special Issue Women in Organic Chemistry)

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Open AccessArticle

In Vitro Antioxidant Activity and In Vivo Anti-Fatigue Effect of Sea Horse (Hippocampus) Peptides

by Zebin Guo, Duanquan Lin, Juanjuan Guo, Yi Zhang and Baodong Zheng

Molecules 2017, 22(3), 482; https://doi.org/10.3390/molecules22030482 - 18 Mar 2017

Cited by 58 | Viewed by 6927

Abstract

This study investigated changes the in vitro antioxidant activity of Hippocampus polypeptides during enzymatic hydrolysis, including the effects of enzyme species, enzyme concentration, material–liquid ratio, hydrolysis time, pH, and temperature of the reaction system. Its in vivo anti-fatigue activity was also studied. Hippocampus [...] Read more.

This study investigated changes the in vitro antioxidant activity of Hippocampus polypeptides during enzymatic hydrolysis, including the effects of enzyme species, enzyme concentration, material–liquid ratio, hydrolysis time, pH, and temperature of the reaction system. Its in vivo anti-fatigue activity was also studied. Hippocampus peptide prepared by papain digestion exhibited the highest 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging rate (71.89% ± 1.50%) and strong hydroxyl radical scavenging rate (75.53% ± 0.98%), compared to those prepared by five other commonly used enzymes (i.e., trypsin, neutral protease, compound protease, flavorzyme, and alkaline protease). Additionally, maximum antioxidant activity of Hippocampus polypeptide prepared by papain digestion was reached after hydrolysis for 40 min at pH 6.0 and 60 °C of the reaction system by using 2000 U/g enzyme and a material–liquid ratio of 1:15. Moreover, compared with the control group, Hippocampus peptide prolonged the swimming time by 33%–40%, stabilized the blood glucose concentration, increased liver glycogen levels, and decreased blood lactate levels and blood urea nitrogen levels in mice (p < 0.01). In conclusion, these results indicated that Hippocampus polypeptide prepared by papain digestion under optimal conditions exhibited high degrees of antioxidant and anti-fatigue activity. Full article

(This article belongs to the Special Issue Selected papers from 2nd International Symposium on Phytochemicals in Medicine and Food (2-ISPMF, Fuzhou, 2017))

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Open AccessArticle

Energy of Intramolecular Hydrogen Bonding in ortho-Hydroxybenzaldehydes, Phenones and Quinones. Transfer of Aromaticity from ipso-Benzene Ring to the Enol System(s)

by Danuta Rusinska-Roszak

Molecules 2017, 22(3), 481; https://doi.org/10.3390/molecules22030481 - 18 Mar 2017

Cited by 36 | Viewed by 12926

Abstract

Intramolecular hydrogen bonding (HB) is one of the most studied noncovalent interactions of molecules. Many physical, spectral, and topological properties of compounds are under the influence of HB, and there are many parameters used to notice and to describe these changes. Hitherto, no [...] Read more.

Intramolecular hydrogen bonding (HB) is one of the most studied noncovalent interactions of molecules. Many physical, spectral, and topological properties of compounds are under the influence of HB, and there are many parameters used to notice and to describe these changes. Hitherto, no general method of measurement of the energy of intramolecular hydrogen bond (E_HB) has been put into effect. We propose the molecular tailoring approach (MTA) for E_HB calculation, modified to apply it to Ar-O-H∙∙∙O=C systems. The method, based on quantum calculations, was checked earlier for hydroxycarbonyl-saturated compounds, and for structures with resonance-assisted hydrogen bonding (RAHB). For phenolic compounds, the accuracy, repeatability, and applicability of the method is now confirmed for nearly 140 structures. For each structure its aromaticity HOMA indices were calculated for the central (ipso) ring and for the quasiaromatic rings given by intramolecular HB. The comparison of calculated HB energies and values of estimated aromaticity indices allowed us to observe, in some substituted phenols and quinones, the phenomenon of transfer of aromaticity from the ipso-ring to the H-bonded ring via the effect of electron delocalization. Full article

(This article belongs to the Special Issue Intramolecular Hydrogen Bonding 2017)

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283 KiB

Open AccessReview

Therapeutic Potentials of Microalgae in the Treatment of Alzheimer’s Disease

by Tosin A. Olasehinde, Ademola O. Olaniran and Anthony I. Okoh

Molecules 2017, 22(3), 480; https://doi.org/10.3390/molecules22030480 - 18 Mar 2017

Cited by 95 | Viewed by 11429

Abstract

Current research is geared towards the discovery of new compounds with strong neuroprotective potential and few or no side effects compared to synthetic drugs. This review focuses on the potentials of extracts and biologically active compounds derived from microalgal biomass for the treatment [...] Read more.

Current research is geared towards the discovery of new compounds with strong neuroprotective potential and few or no side effects compared to synthetic drugs. This review focuses on the potentials of extracts and biologically active compounds derived from microalgal biomass for the treatment and management of Alzheimer’s disease (AD). Microalgal research has gained much attention recently due to its contribution to the production of renewable fuels and the ability of alga cells to produce several secondary metabolites such as carotenoids, polyphenols, sterols, polyunsaturated fatty acids and polysaccharides. These compounds exhibit several pharmacological activities and possess neuroprotective potential. The pathogenesis of Alzheimer’s disease (AD) involves complex mechanisms that are associated with oxidative stress, cholinergic dysfunction, neuronal damage, protein misfolding and aggregation. The antioxidant, anticholinesterase activities as well as the inhibitory effects of some bioactive compounds from microalgae extracts on β-amyloid aggregation and neuronal death are discussed extensively. Phytochemical compounds from microalgae are used as pharmaceuticals, nutraceuticals and food supplements, and may possess neuroprotective potentials that are relevant to the management and/or treatment of AD. Full article

(This article belongs to the Collection Neuroprotection Mediated by Natural Products and Their Chemical Derivatives)

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Open AccessArticle

Design of New Benzo[h]chromene Derivatives: Antitumor Activities and Structure-Activity Relationships of the 2,3-Positions and Fused Rings at the 2,3-Positions

by Rawda M. Okasha, Fawzia F. Alblewi, Tarek H. Afifi, Arshi Naqvi, Ahmed M. Fouda, Al-Anood M. Al-Dies and Ahmed M. El-Agrody

Molecules 2017, 22(3), 479; https://doi.org/10.3390/molecules22030479 - 18 Mar 2017

Cited by 48 | Viewed by 7276

Abstract

A series of novel 4H-benzo[h]chromenes 4, 6–11, 13, 14; 7H-benzo[h]chromeno[2,3-d]pyrimidines 15–18, 20, and 14H-benzo[h]chromeno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives [...] Read more.

A series of novel 4H-benzo[h]chromenes 4, 6–11, 13, 14; 7H-benzo[h]chromeno[2,3-d]pyrimidines 15–18, 20, and 14H-benzo[h]chromeno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives 19a–e, 24 was prepared. The structures of the synthesized compounds were characterized on the basis of their spectral data. Some of the target compounds were examined for their antiproliferative activity against three cell lines; breast carcinoma (MCF-7), human colon carcinoma (HCT-116) and hepatocellular carcinoma (HepG-2). The cytotoxic behavior has been tested using MTT assay and the inhibitory activity was referenced to three standard anticancer drugs: vinblastine, colchicine and doxorubicin. The bioassays demonstrated that some of the new compounds exerted remarkable inhibitory effects as compared to the standard drugs on the growth of the three tested human tumor cell lines. The structure–activity relationships (SAR) study highlights that the antitumor activity of the target compounds was significantly affected by the lipophilicity of the substituent at 2- or 3- and fused rings at the 2,3-positions. Full article

(This article belongs to the Collection Heterocyclic Compounds)

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Open AccessArticle

Quality Evaluation and Chemical Markers Screening of Salvia miltiorrhiza Bge. (Danshen) Based on HPLC Fingerprints and HPLC-MSⁿ Coupled with Chemometrics

by Wenyi Liang, Wenjing Chen, Lingfang Wu, Shi Li, Qi Qi, Yaping Cui, Linjin Liang, Ting Ye and Lanzhen Zhang

Molecules 2017, 22(3), 478; https://doi.org/10.3390/molecules22030478 - 17 Mar 2017

Cited by 65 | Viewed by 7371

Abstract

Danshen, the dried root of Salvia miltiorrhiza Bge., is a widely used commercially available herbal drug, and unstable quality of different samples is a current issue. This study focused on a comprehensive and systematic method combining fingerprints and chemical identification with chemometrics for [...] Read more.

Danshen, the dried root of Salvia miltiorrhiza Bge., is a widely used commercially available herbal drug, and unstable quality of different samples is a current issue. This study focused on a comprehensive and systematic method combining fingerprints and chemical identification with chemometrics for discrimination and quality assessment of Danshen samples. Twenty-five samples were analyzed by HPLC-PAD and HPLC-MSⁿ. Forty-nine components were identified and characteristic fragmentation regularities were summarized for further interpretation of bioactive components. Chemometric analysis was employed to differentiate samples and clarify the quality differences of Danshen including hierarchical cluster analysis, principal component analysis, and partial least squares discriminant analysis. Consistent results were that the samples were divided into three categories which reflected the difference in quality of Danshen samples. By analyzing the reasons for sample classification, it was revealed that the processing method had a more obvious impact on sample classification than the geographical origin, it induced the different content of bioactive compounds and finally lead to different qualities. Cryptotanshinone, trijuganone B, and 15,16-dihydrotanshinone I were screened out as markers to distinguish samples by different processing methods. The developed strategy could provide a reference for evaluation and discrimination of other traditional herbal medicines. Full article

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167 KiB

Open AccessEditorial

Flavonoids: From Structure to Health Issues

by Celestino Santos-Buelga and Arturo San Feliciano

Molecules 2017, 22(3), 477; https://doi.org/10.3390/molecules22030477 - 17 Mar 2017

Cited by 48 | Viewed by 7443

Abstract

Flavonoids are one of the largest groups of plant secondary metabolites.[...] Full article

(This article belongs to the Special Issue Flavonoids: From Structure to Health Issues)

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Open AccessArticle

Analysis of Chemical Constituents of Melastoma dodecandrum Lour. by UPLC-ESI-Q-Exactive Focus-MS/MS

by Jinfeng Wang, Ziyao Jia, Zhihao Zhang, Yutong Wang, Xi Liu, Linghua Wang and Ruichao Lin

Molecules 2017, 22(3), 476; https://doi.org/10.3390/molecules22030476 - 17 Mar 2017

Cited by 72 | Viewed by 8002

Abstract

The ethnic drug Melastoma dodecandrum Lour. (MDL) is widely distributed throughout South China, and is the major component of Gong Yan Ping Tablets/Capsules and Zi Di Ning Xue San. Although the pharmacological effects of MDL have been well documented, its chemical profile has [...] Read more.

The ethnic drug Melastoma dodecandrum Lour. (MDL) is widely distributed throughout South China, and is the major component of Gong Yan Ping Tablets/Capsules and Zi Di Ning Xue San. Although the pharmacological effects of MDL have been well documented, its chemical profile has not been fully determined. In this study, we have developed a rapid and sensitive UPLC-ESI-Q-Exactive Focus-MS/MS method to characterize the chemical constituents of MDL in the positive and negative ionization modes. A comparison of the chromatographic and spectrometric data obtained using this method with data from databases, the literature and reference standards allowed us to identify or tentatively characterize 109 compounds, including 26 fatty acids, 26 organic acids, 33 flavonoids, six tannins, 10 triterpenoids, two steroids and six other compounds. Notably, 55 of the compounds characterized in this study have never been detected before in this plant. The information obtained in this study therefore enriches our understanding of the chemical composition of MDL and could be used in quality control, pharmacological research and the development of drugs based on MDL. In addition, this study represents the first reported comprehensive analysis of the chemical constituents of MDL. Full article

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Open AccessArticle

Briarenols C–E, New Polyoxygenated Briaranes from the Octocoral Briareum excavatum

by Nan-Fu Chen, Yin-Di Su, Tsong-Long Hwang, Zuo-Jian Liao, Kuan-Hao Tsui, Zhi-Hong Wen, Yang-Chang Wu and Ping-Jyun Sung

Molecules 2017, 22(3), 475; https://doi.org/10.3390/molecules22030475 - 17 Mar 2017

Cited by 14 | Viewed by 4199

Abstract

Three new polyoxygenated briarane diterpenoids, briarenols C–E (1–3), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1–3 were elucidated by interpretation of spectroscopic data, and the methylenecyclohexane ring in 1 was found to [...] Read more.

Three new polyoxygenated briarane diterpenoids, briarenols C–E (1–3), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1–3 were elucidated by interpretation of spectroscopic data, and the methylenecyclohexane ring in 1 was found to exist in a twisted boat conformation. Briarenol D (2) displayed an inhibitory effect on the release of elastase by human neutrophils with an IC₅₀ value of 4.65 μM. Briarenol E (3) was found to inhibit the protein expression of pro-inflammatory inducible nitric oxide synthase (iNOS) in a murine macrophage-like cell line, RAW 264.7, stimulated with lipopolysaccharides (LPS). Full article

(This article belongs to the Section Natural Products Chemistry)

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