23,937 results match your criteria spectroscopic nmr

Binary System of Polyethylene Glycol 200 (1) + 3-Dimethylamino-1-propylamine (2) for CO Absorption: Thermophysical Properties and Spectroscopic Study.

ACS Omega 2021 Apr 31;6(14):9898-9909. Epub 2021 Mar 31.

Key Laboratory of Green Chemical and Clean Energy Technology, School of Chemistry and Chemical Engineering, Guizhou University, Guiyang 550025, P. R. China.

As the concentration of CO in the atmosphere keeps increasing, the development of a highly efficient CO absorbent is highly desired. In this work, a binary mixture system of polyethylene glycol 200 (PEG 200) () + 3-dimethylamino-propylamine (DMAPA) () was used for CO absorption. Considering the importance of thermophysical properties to binary solutions, the densities and viscosities of the PEG 200 () + DMAPA () mixture were measured at = (298. Read More

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Optical Anion Receptors with Urea/Thiourea Subunits on a TentaGel Support.

ACS Omega 2021 Apr 31;6(14):9381-9390. Epub 2021 Mar 31.

Departamento de Investigación en Polímeros y Materiales, Universidad de Sonora, Blvd. Luis Encinas y Calle Rosales S/N, Hermosillo 83000, Sonora, Mexico.

Two simple chemosensors with urea (L1) and thiourea (L2) groups were synthesized and studied by different spectroscopic techniques. Both receptors can sense acetate (Ac), dihydrogen phosphate (HPO), and fluoride (F) anions, accompanied by changes in UV-vis and H NMR spectra, and an optical response is observed as a color change of the solutions due to deprotonation and hydrogen-bonding processes. Also, L1 and L2 were supported on TentaGel resins (R1 and R2), and their fluoride-sensing properties in DMSO and water solutions were studied. Read More

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A Facile and Catalyst-Free Microwave-Promoted Multicomponent Reaction for the Synthesis of Functionalised 1,4-Dihydropyridines With Superb Selectivity and Yields.

Front Chem 2021 31;9:638832. Epub 2021 Mar 31.

School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa.

We report a highly efficient green protocol for developing a novel library of 1,2,4-triazole-tagged 1,4-dihydropyridine analogs through the one-pot process from the four-component fusion of the 1-1,2,4-triazol-3-amine with different chosen aldehydes, diethyl acetylenedicarboxylate, and active methylene compounds in a water medium under microwave irradiation and catalyst-free conditions. Excellent yields (94-97%) of the target products were achieved with high selectivity with a short reaction time (<12 min) at room temperature. The structures of the synthesized pyrimidine analogs were established by NMR and HRMS spectroscopic analysis. Read More

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New Bioactive Sesquiterpeniods From the Plant Endophytic Fungus .

Front Microbiol 2021 31;12:641504. Epub 2021 Mar 31.

State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.

Three new secondary metabolites pestalothenins A-C (-), including two new humulane-derived sesquiterpeniods ( and ) and one new caryophyllene-derived sesquiterpeniod (), together with five known compounds (-) were isolated from the crude extract of the plant endophytic fungus (N635). Their structures were elucidated by the extensive analyses of HRESIMS and NMR spectroscopic data. The absolute configurations of - were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Read More

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Isolation, structural characterization and quality control strategy of an unknown process-related impurity in sugammadex sodium.

J Pharm Biomed Anal 2021 Apr 15;200:114072. Epub 2021 Apr 15.

Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China; Jiangsu Key Laboratory of Marine Biological Resources and Environment, Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, School of Pharmacy, Jiangsu Ocean University, Lianyungang, 222005, China. Electronic address:

Sugammadex sodium is the first selective relaxant binding agent (SRBA) indicated for reversal of neuromuscular blockade induced by rocuronium or vecuronium during surgery. The chemical synthesis of sugammadex involved the nucleophilic substitution reaction between 6-per-deoxy-6-per-halo-γ-cyclodextrin and 3-mercaptopropionic acid under basic conditions. During the manufacture of sugammadex sodium, an unknown process-related impurity was observed in pilot batches in the range of 0. Read More

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A new prenylated benzoquinone from Cyathocalyx pruniferus abrogates LPS-induced inflammatory responses associated with PGE, COX-2 and cytokines biosynthesis in human plasma.

Inflammopharmacology 2021 Apr 17. Epub 2021 Apr 17.

Faculty of Pharmacy, MAHSA University, Bandar Saujana Putra, 42610, Jenjarom, Selangor, Malaysia.

In our previous laboratory findings, Cyathocalyx pruniferus extracts exhibited platelet-activating factor inhibition, suggesting their anti-inflammatory potential. Hence, this study was designed with the aim to isolate phyto-constituents from C. pruniferus with potent anti-inflammatory activities. Read More

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The molecular pH-response mechanism of the plant light-stress sensor PsbS.

Nat Commun 2021 04 16;12(1):2291. Epub 2021 Apr 16.

Dept. of Solid-State NMR, Leiden Inst. of Chemistry, Leiden University, Leiden, The Netherlands.

Plants need to protect themselves from excess light, which causes photo-oxidative damage and lowers the efficiency of photosynthesis. Photosystem II subunit S (PsbS) is a pH sensor protein that plays a crucial role in plant photoprotection by detecting thylakoid lumen acidification in excess light conditions via two lumen-faced glutamates. However, how PsbS is activated under low-pH conditions is unknown. Read More

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Cornus sanguinea Fruits: a Source of Antioxidant and Antisenescence Compounds Acting on Aged Human Dermal and Gingival Fibroblasts.

Planta Med 2021 Apr 15. Epub 2021 Apr 15.

Dipartimento di Farmacia, Università di Pisa, Pisa, Italy.

Five new compounds, a flavonol glycoside (1: ), a megastigmane (2: ), 2 cyclohexylethanoids (3, 4: ), and a phenylethanoid derivative (5: ), together with 15 known compounds (6: -20: ) including flavonoid glycosides, cyclohexylethanoids, and phenolic compounds, have been isolated from drupes. All the structures have been determined by 1D and 2D NMR spectroscopic analysis and mass spectrometry data. The antioxidant capability of the most representative isolated compounds was evaluated in the hydrogen peroxide (HO)-induced premature cellular senescence model of human dermal and gingival fibroblasts. Read More

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Two new aromatic derivatives from and their α-glucosidase inhibitory activities.

Nat Prod Res 2021 Apr 16:1-8. Epub 2021 Apr 16.

School of Pharmacy, Lanzhou University, Lanzhou, People's Republic of China.

The ethanol extract of the roots of was subjected to chromatographic fractionation, which result in the isolation and characterization of two new aromatic derivatives 2,3-dihydroxypropyl 2,4-dihydroxy-3,6-dimethylbenzoate () and 2-oxopropyl 3-hydroxy-4-methoxybenzoate (), along with three known compounds pilosulinene A (), pollenfuran B () and (+)-pinoresinol (). Their structures were demonstrated by HRESIMS and spectroscopic methods including NMR and IR. It is worth noting that compound was isolated for the first time from the genus . Read More

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Piperazine-2,5-dione derivatives and an α-pyrone polyketide from Penicillium griseofulvum and their immunosuppression activity.

Phytochemistry 2021 Apr 12;186:112708. Epub 2021 Apr 12.

Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China. Electronic address:

Four undescribed piperazine-2,5-dione derivatives designated janthinolides C-F, and an α-pyrone-containing polyketide namely trichopyrone C, were isolated from the extract of the fungus Penicillium griseofulvum along with four known products. Among them, janthinolide C represents the first naturally occured piperazine-2,5-dione analogue featuring a cleavaged piperazinedione ring with an oxime group, while the structure of janthinolide D possesses a rare N-methoxy group in natural products. Their structures and absolute stereochemistry were elucidated based on spectroscopic data, theoretical NMR and ECD calculations, Snatzke's method, and modified Mosher's method. Read More

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Ximaoglaucumins A - F, new cembranoids with anti-inflammatory activities from the South China Sea soft coral Sarcophyton glaucum.

Bioorg Med Chem 2021 Apr 2;38:116139. Epub 2021 Apr 2.

School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555, Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China. Electronic address:

Six new cembrane-type diterpenoids, namely ximaoglaucumins A-F (1-6), along with fifteen known related ones (7-10 and 14-24), have been isolated from the soft coral Sarcophyton glaucum collected off the Ximao Island in the South China Sea. Their structures, including absolute stereochemistry, were elucidated by extensive spectroscopic analysis, quantum mechanical nuclear magnetic resonance (QM-NMR) methods, X-ray diffraction analysis, chemical methods, as well as comparison with the reported data in the literature. Further, detailed analysis of spectroscopic data of 7 not only clarified the confusions regarding 7, 11 (sarcophytolol) and 12/13 (sarcotrocheliol) in the literature, but also led to revise the structure of 11, which was mis-assigned due to careless/erroneous interpretation of the 2D NMR spectra, and to correct the structures of 12/13, which were both wrongly depicted. Read More

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Programmable Synthesis of Silver Wheels.

Inorg Chem 2021 Apr 15. Epub 2021 Apr 15.

Department of Chemistry, Pohang University of Science and Technology, Pohang 37673, Republic of Korea.

The synthesis of sandwich-shaped multinuclear silver complexes with planar penta- and tetranuclear wheel-shaped silver units and a central anion, [Ag()(A)](OTf), , = 4 or 5 and A = OH or F or Cl, is reported, along with complete spectroscopic and structural characterization. An NMR mechanistic study reveals that silver complexes were formed in the following order: → → → . The central hydroxides in and exhibit exotic physical properties due to the confined environment inside the complex. Read More

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Infrared and NMR Spectroscopic Fingerprints of the Asymmetric H O Complex in Solution.

Chemphyschem 2021 Apr 14. Epub 2021 Apr 14.

Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva, 84105, Israel.

The front cover artwork is provided by the groups of Prof. Ehud Pines (BGU, Israel) and Dr. Benjamin Fingerhut (MBI, Berlin). Read More

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Choices of chromatographic methods as stability indicating assays for pharmaceutical products: A review.

Heliyon 2021 Mar 27;7(3):e06553. Epub 2021 Mar 27.

School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, 47500 Petaling Jaya, Selangor Darul Ehsan, Malaysia.

Stability indicating assay describes a technique which is used to analyse the stability of drug substance or active pharmaceutical ingredient (API) in bulk drug and pharmaceutical products. Stability indicating assay must be properly validated as per ICH guidelines. The important components in a stability indicating assay include sensitivity, specificity, accuracy, reliability, reproducibility and robustness. Read More

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Nine Unique Iridoids and Iridoid Glycosides From .

Front Chem 2021 29;9:657028. Epub 2021 Mar 29.

National Center for Research and Development of Edible Fungus Processing Technology, Henan University, Kaifeng, China.

is a medical and edible Chinese herb with high nutritional and medicinal value. The continuing study of its chemical constituents led to the discovery of nine unique iridoids and iridoid glycosides, including three new iridoids (-) and six previously unknown irioid glycosides (-), and one known compound (). Among them, compound was a deformed iridoid, while compounds , -, and formed a new ring in their skeletons which was uncommon in this genus. Read More

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Crystal, spectroscopic and quantum mechanics studies of Schiff bases derived from 4-nitrocinnamaldehyde.

Sci Rep 2021 Apr 14;11(1):8151. Epub 2021 Apr 14.

Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, Durban, 4041, South Africa.

Two Schiff bases, (E)-1-(4-methoxyphenyl)-N-((E)-3-(4-nitrophenyl)allylidene)methanamine (compound 1) and (E)-N-((E)-3-(4-nitrophenyl)allylidene)-2-phenylethanamine (compound 2) have been synthesized and characterized using spectroscopic methods; time of flight MS, H and C NMR, FT-IR, UV-VIS, photoluminescence and crystallographic methods. The structural and electronic properties of compounds 1 and 2 in the ground state were also examined using the DFT/B3LYP functional and 6-31 + G(d,p) basis set, while the electronic transitions for excited state calculations were carried out using the TD-DFT/6-31 + G(d,p) method. The Schiff base compounds, 1 and 2 crystallized in a monoclinic crystal system and the P2/c space group. Read More

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Anti-ulcerogenic effect of methanolic extract of Elaeagnus conferta Roxb. seeds in Wistar rats.

J Ethnopharmacol 2021 Apr 11:114115. Epub 2021 Apr 11.

Rayat Institute of Pharmacy, Railmajra, SBS Nagar, Punjab, India. Electronic address:

Ethnopharmacological Relevance: Elaeagnus conferta Roxb. (Elaeagnaceae) is a subtropical shrub mainly native to India, Vietnam, Malaysia and South China, whose various parts are used for treatment of diabetes, gastric ulcers, pain, oxidative stress and pulmonary disorders. Though the other parts of the plant have been reported for their ethnic use i. Read More

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Bioactive Dimeric Tetrahydroxanthones with 2,2'- and 4,4'-Axial Linkages from the Entomopathogenic Fungus .

J Nat Prod 2021 Apr 14. Epub 2021 Apr 14.

National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Thailand Science Park, Phaholyothin Road, Khlong Luang, Pathum Thani 12120, Thailand.

Thirteen tetrahydroxanthone dimers, -ascherxanthone A (), ascherxanthones C-G (-), and confluxanthones A-G (-), were isolated from the entomopathogenic fungus BCC53152. The chemical structures were determined based on analysis of NMR spectroscopic and mass spectrometric data. The absolute configurations of compounds and were confirmed by single-crystal X-ray diffraction experiments, while the configurations of other compounds were assigned based upon evidence from NOESY and NOEDIFF experiments, modified Mosher's method, and ECD spectroscopic data together with biogenetic considerations. Read More

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Dysiscalarones A-E, scalarane sesterterpenoids with nitric oxide production inhibitory activity from marine sponge Dysidea granulosa.

Bioorg Chem 2021 Mar 5;111:104791. Epub 2021 Mar 5.

Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China. Electronic address:

Dysiscalarones A-E (1-5), five new scalarane-type bishomoscalarane sesterterpenoids, were isolated from marine sponge Dysidea granulosa collected from the South China Sea, together with two known ones, honulactone A (6) and phyllofolactone I (7). The new structures were determined by extensive spectroscopic analysis including HR-ESI-MS and 1D and 2D NMR data, and their absolute configurations were assigned by single crystal X-ray diffraction analyses. The inhibitory activity of all the seven isolates on the production of nitric oxide (NO) stimulated by lipopolysaccharide (LPS) in mouse RAW 264. Read More

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Phytochemicals from twigs of and their antioxidation kinetics of oxymyoglobin.

Nat Prod Res 2021 Apr 13:1-5. Epub 2021 Apr 13.

Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand.

The phytochemical investigation of crude -hexane and ethyl acetate extracts from twigs of (Kurz) led to the isolation of 14 known compounds. Their structures were elucidated by spectroscopic techniques (IR, H NMR, C NMR, and 2D NMR) as well as mass spectrometry. These structures were characterized as -sitosterol (), lupeol (), vanilic acid (), 5,7-dihydroxychromone (), (+)-mellein (), isoliquiritigenin (), 7-hydroxyemodin (), physion (), aromadendrin (), naringenin (), apigenin (), luteolin (), chrysoeriol () and kaempferol (). Read More

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Structurally diverse diterpenoids with eight carbon skeletons from Rhododendron micranthum and their antinociceptive effects.

Bioorg Chem 2021 Mar 29;111:104870. Epub 2021 Mar 29.

Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China. Electronic address:

Seventeen diterpenoids (1-17), classified into eight diverse carbon skeleton types, grayanane (1, 2, and 12), micranthane (3, 4, and 13), mollane (5-7 and 14), 1,5-seco-grayanane (8), kalmane (9-11), 1,5-seco-kalmane (15), A-homo-B-nor-ent-kaurane (16), and leucothane (17), respectively, were isolated from the leaves extract of Rhododendron micranthum. Among them, diterpenoids 1-9 are new compounds and their structures were elucidated via extensive spectroscopic methods, quantum chemical calculations including the C NMR-DP4+ analysis and electronic circular dichroism (ECD) calculations, and the single-crystal X-ray diffraction analysis. Micranthanol A (1) represents the first example of a 5αH,9αH-grayanane diterpenoid and a 6-hydroxy-6,10-epoxygrayanane diterpenoid, and micranthanone B (3) is the first 6,10-epoxymicranthane and the 5α-hydroxy-micranthane diterpenoids. Read More

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Marinoterpins A-C: Rare Linear Merosesterterpenoids from Marine-Derived Actinomycete Bacteria of the Family Streptomycetaceae.

J Org Chem 2021 Apr 12. Epub 2021 Apr 12.

Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States.

The chemical examination of two undescribed marine actinobacteria has yielded three rare merosesterterpenoids, marinoterpins A-C (-, respectively). These compounds were isolated from the culture broth extracts of two marine-derived actinomycetes associated with the family Streptomycetaceae, (our strains were CNQ-253 and AJS-327). The structures of the new compounds were determined by extensive interpretation of 1D and 2D NMR, MS, and combined spectroscopic data. Read More

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Diterpenoids from Roots of and Toxicity against Human Cancer Cell Lines.

Iran J Pharm Res 2020 ;19(4):85-94

Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.

Further investigations on phytochemical constituents of dichloromethane extract from roots of ( led to the isolation and identification of eight known diterpenoids from this plant for the first time. The chemical structures of the purified compounds were elucidated using spectroscopic analyses including EI-MS, H and C NMR and by comparison of the resulting spectra with those reported in the literature. Then, the cytotoxic activity of identified compounds was examined against two human cancer cell lines MCF-7 (human breast adenocarcinoma) and K562 (human chronic myelogenous leukemia). Read More

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January 2020

Isolation of Two Isochlorogenic Acid Isomers from Phenolic Rich Fraction of Krasch.

Iran J Pharm Res 2020 ;19(4):59-66

Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran.

Total phenolic content (TPC) and antioxidant capacity of five different extracts (petroleum ether (40-60), dichloromethane, ethyl acetate, ethanol and ethanol-water (1:1 v/v)) of aerial parts were determined and phytochemical study on the most promising extract was carried out. Folin-Ciocalteu method, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging test, β-carotene bleaching (BCB) method, and ferrous ion chelating (FIC) assay were performed. Vacuum liquid chromatography (VLC) and semi-preparative HPLC were used for bioassay-guided phytochemical isolation. Read More

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January 2020

New Thio-Compounds and Monoterpenes With Anti-inflammatory Activities From the Fungus sp. CYH26.

Front Microbiol 2021 25;12:668938. Epub 2021 Mar 25.

Key Laboratory of Chemistry and Engineering of Forest Products, State Ethnic Affairs Commission, Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products, School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning, China.

Two new thio-compounds named aspergerthinol A and B ( and ) and two new monoterpenes named aspergerthinacids A and B ( and ) were isolated from the fungus sp. CYH26 from the rhizosphere soil of Decne. The structures of compounds were elucidated by spectroscopic data and quantum NMR and ECD calculations. Read More

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Crystal structure of higher plant heme oxygenase-1 and its mechanism of interaction with ferredoxin.

J Biol Chem 2020 Dec 24;296:100217. Epub 2020 Dec 24.

Institute for Protein Research, Osaka University, Suita, Osaka, Japan; Department of Macromolecular Science, Osaka University, Toyonaka, Osaka, Japan. Electronic address:

Heme oxygenase (HO) converts heme to carbon monoxide, biliverdin, and free iron, products that are essential in cellular redox signaling and iron recycling. In higher plants, HO is also involved in the biosynthesis of photoreceptor pigment precursors. Despite many common enzymatic reactions, the amino acid sequence identity between plant-type and other HOs is exceptionally low (∼19. Read More

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December 2020

Insight on the fractionations and structural characterizations of innovative antidiarrheal compounds screened from leaves of Psidium guajava of local origin in Pakistan.

Pak J Pharm Sci 2020 Sep;33(5(Supplementary)):2323-2329

Imran Adrees College of Pharmacy, 3Km Daska Road, Sialkot, Pakistan.

Numerous ailments have been effectively treated with natural plants for long time all over the world. Plants provided a back bone for the exploration of novel medicinal compounds. Therefore, chief focus of our study was to isolate the biologically active compounds from the plant source and evaluate their antidiarrheal potentials, as diarrhea is still the most dominant disease in developing countries. Read More

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September 2020

Prenylated Coumaric Acids from Beneficially Modulate Adipogenesis.

J Nat Prod 2021 Apr 8. Epub 2021 Apr 8.

Center for Natural Product Technologies, Pharmacognosy Institute, and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Illinois 60612, United States.

Two new diprenylated coumaric acid isomers ( and ) and two known congeners, capillartemisin A () and B (), were isolated from as bioactive markers using bioactivity-guided HPLC fractionation. Their structures were determined by spectroscopic means, including 1D and 2D NMR methods and LC-MS, with their purity assessed by 1D H pure shift qNMR spectroscopic analysis. The bioactivity of compounds was evaluated by enhanced accumulation of lipids, as measured using Oil Red O staining, and by increased expression of several adipocyte marker genes, including adiponectin in 3T3-L1 adipocytes relative to untreated negative controls. Read More

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Ultrafast Nonlinear Optical and Structure-Property Relationship Studies of Pyridine-Based Anthracene Chalcones Using -Scan, Degenerate Four-Wave Mixing, and Computational Approaches.

J Phys Chem B 2021 Apr 8. Epub 2021 Apr 8.

X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, George Town, Penang 11800, Malaysia.

The structural, thermal, linear, and femtosecond third-order nonlinear optical (NLO) properties of two pyridine-based anthracene chalcones, (2)-1-(anthracen-9-yl)-3-(pyridin-2-yl)prop-2-en-1-one () and (2)-1-(anthracen-9-yl)-3-(pyridin-3-yl)prop-2-en-1-one (), were investigated. These two chalcones were synthesized following the Claisen-Schmidt condensation method. Optically transparent single crystals were achieved using a slow evaporation solution growth technique. Read More

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Spectroscopic Evidence for a Covalent Sigma Au-C Bond on Au Surfaces Using C Isotope Labeling.

JACS Au 2021 Mar 23;1(3):362-368. Epub 2021 Feb 23.

Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany.

The Au-C linkage has been demonstrated as a robust interface for coupling thin organic films on Au surfaces. However, the nature of the Au-C interaction remains elusive up to now. Surface-enhanced Raman spectroscopy was previously used to assign a band at 412 cm as a covalent sigma Au-C bond for films generated by spontaneous reduction of the 4-nitrobenzenediazonium salt on Au nanoparticles. Read More

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