Journal articles: 'Chemical compound'

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Wang, Hongwei, Edgar Chambers, and Jianquan Kan. "Sensory Characteristics of Combinations of Phenolic Compounds Potentially Associated with Smoked Aroma in Foods." Molecules 23, no. 8 (July 26, 2018): 1867. http://dx.doi.org/10.3390/molecules23081867.

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The sensory characteristics of phenolic compounds combinations were evaluated. A highly trained descriptive panel evaluated combinations of chemicals (two chemicals at a time) containing either one smoky aroma and one non-smoky aroma chemical compound, two smoky aroma chemicals, or two non-smoky aroma chemicals. The non-smoky compounds had been associated with smoke aroma in other studies, but were not found to be smoky when tested individually. Smoked flavor characteristics and intensities were changed significantly when two phenolic compounds were combined. Non-smoky phenolic compounds often contributed the smoked flavor when combined with one smoky phenolic compound or another non-smoky phenolic compound. It is necessary to understand the sensory characteristics of compound combinations as well as individual compounds.

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Klein, Ursula. "Origin of the Concept Chemical Compound." Science in Context 7, no. 2 (1994): 163–204. http://dx.doi.org/10.1017/s0269889700001666.

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The ArgumentMost historians of science share the conviction that the incorporation of the corpuscular theory into seventeenth-century chemistry was the beginning of modern chemistry. My thesis in this paper is that modern chemisty started with the concept of the chemicl compound, which emerged at the end of the seventeenth and the beginning of the eighteenth century, without any signifivant influence of the corpuscular theory. Rather the historical reconstruction of the emergence of this concept shows that it resulted from the reflection on the chemical operations in the sixteenth-century metallurgy and seventeenth-century pharmacy. I argue that the reversibility of these operations and their understanding as crafts (metallurgy) or chemical arts (pharmacy) were decisive factors for the emergence of the first ideas about chemical compounds in the seventeenth-century pharmaceutical works written by pharmaceutically trained authors, influenced by the Paracelsian image of nature. There is a direct line of descent from these authors to E.F.Geoffroy (1675–1742), who integrated the first scattered ideas of chemical compound into a general concept comprising chemical artefacts as well as natural bodies.

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Dofuor, Aboagye Kwarteng, Temitayo Samson Ademolue, Cynthia Mmalebna Amisigo, Kwaku Kyeremeh, and Theresa Manful Gwira. "Chemical Derivatization and Characterization of Novel Antitrypanosomals for African Trypanosomiasis." Molecules 26, no. 15 (July 25, 2021): 4488. http://dx.doi.org/10.3390/molecules26154488.

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The search for novel antitrypanosomals and the investigation into their mode of action remain crucial due to the toxicity and resistance of commercially available antitrypanosomal drugs. In this study, two novel antitrypanosomals, tortodofuordioxamide (compound 2) and tortodofuorpyramide (compound 3), were chemically derived from the natural N-alkylamide tortozanthoxylamide (compound 1) through structural modification. The chemical structures of these compounds were confirmed through spectrometric and spectroscopic analysis, and their in vitro efficacy and possible mechanisms of action were, subsequently, investigated in Trypanosoma brucei (T. brucei), one of the causative species of African trypanosomiasis (AT). The novel compounds 2 and 3 displayed significant antitrypanosomal potencies in terms of half-maximal effective concentrations (EC50) and selectivity indices (SI) (compound 1, EC50 = 7.3 μM, SI = 29.5; compound 2, EC50 = 3.2 μM, SI = 91.3; compound 3, EC50 = 4.5 μM, SI = 69.9). Microscopic analysis indicated that at the EC50 values, the compounds resulted in the coiling and clumping of parasite subpopulations without significantly affecting the normal ratio of nuclei to kinetoplasts. In contrast to the animal antitrypanosomal drug diminazene, compounds 1, 2 and 3 exhibited antioxidant absorbance properties comparable to the standard antioxidant Trolox (Trolox, 0.11 A; diminazene, 0.50 A; compound 1, 0.10 A; compound 2, 0.09 A; compound 3, 0.11 A). The analysis of growth kinetics suggested that the compounds exhibited a relatively gradual but consistent growth inhibition of T. brucei at different concentrations. The results suggest that further pharmacological optimization of compounds 2 and 3 may facilitate their development into novel AT chemotherapy.

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Tang, Xiaoling, and Ting Peng. "Chemical Compound Chemical Treatment in Animal Husbandry." Journal of Chemistry 2020 (November 20, 2020): 1–8. http://dx.doi.org/10.1155/2020/4263124.

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The acidulant is widely used in the production of animal husbandry, and its use is affected by many factors, including environmental factors, dosage, diet composition, and animal’s own factors, so only the correct use of the acidulant can bring good results in animal production and financial income. This article takes acidifier as an example to study the application of compound chemical treatment in livestock farms. In this paper, the effect of using acidulant in the first 1 to 3 weeks after early weaning of piglets is obvious through this experimental study. The effect gradually decreases after 3 weeks and basically has no effect after 4 weeks. Experimental studies have found that the combination of organic acids, antibiotics, and high copper is the most effective. These three have different functions and have complementary or additive effects. Under harsh feeding conditions, especially when the environmental sanitation and environmental conditions are relatively poor, the effect of acidulants is better than good feeding conditions. Experimental data show that fulvic acid depletes milk’s somatic cells in a short period of time and then quickly activates immune function, which is indicated by the increase in lymphocytes in the blood. When a large number of somatic cells migrate to the breast, the somatic cells in milk will also increase, thereby improving the immunity mediated by human cells. The experimental results show that the BFA formula added 1% to the cattle feed. After the research control of this experiment, the milk output increased by 9–17%, and the quality milk output increased by 19.12%, so the use of acidulant increased feed compensation and reduces gastrointestinal diseases and the reproduction of microorganisms in the rumen of dairy cows.

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de la Vega de León, Antonio, and Jürgen Bajorath. "Design of chemical space networks incorporating compound distance relationships." F1000Research 5 (November 4, 2016): 2634. http://dx.doi.org/10.12688/f1000research.10021.1.

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Networks, in which nodes represent compounds and edges pairwise similarity relationships, are used as coordinate-free representations of chemical space. So-called chemical space networks (CSNs) provide intuitive access to structural relationships within compound data sets and can be annotated with activity information. However, in such similarity-based networks, distances between compounds are typically determined for layout purposes and clarity and have no chemical meaning. By contrast, inter-compound distances as a measure of dissimilarity can be directly obtained from coordinate-based representations of chemical space. Herein, we introduce a CSN variant that incorporates compound distance relationships and thus further increases the information content of compound networks. The design was facilitated by adapting the Kamada-Kawai algorithm. Kamada-Kawai networks are the first CSNs that are based on numerical similarity measures, but do not depend on chosen similarity threshold values.

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de la Vega de León, Antonio, and Jürgen Bajorath. "Design of chemical space networks incorporating compound distance relationships." F1000Research 5 (November 30, 2016): 2634. http://dx.doi.org/10.12688/f1000research.10021.2.

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Networks, in which nodes represent compounds and edges pairwise similarity relationships, are used as coordinate-free representations of chemical space. So-called chemical space networks (CSNs) provide intuitive access to structural relationships within compound data sets and can be annotated with activity information. However, in such similarity-based networks, distances between compounds are typically determined for layout purposes and clarity and have no chemical meaning. By contrast, inter-compound distances as a measure of dissimilarity can be directly obtained from coordinate-based representations of chemical space. Herein, we introduce a CSN variant that incorporates compound distance relationships and thus further increases the information content of compound networks. The design was facilitated by adapting the Kamada-Kawai algorithm. Kamada-Kawai networks are the first CSNs that are based on numerical similarity measures, but do not depend on chosen similarity threshold values.

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Luo, Yong Ming, Xiao Yin Yin, and Ming Yong Xie. "Chemical Constituents and Bioactivity of Chloranthus Multistachys." Advanced Materials Research 343-344 (September 2011): 1189–92. http://dx.doi.org/10.4028/www.scientific.net/amr.343-344.1189.

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From Chloranthus multistachys, three sesquiterpene lactones, multislactone (1), codonolactone(2), lasianthuslactone A(3), and three diterpenes, 12R,15- dihydroxylabda-8(17), 13E- dien-19-oic acid(4), 12(S),15- dihydroxy labda-8(17), 13E-dien- 19-oic acid(5), 12-oxo-15- hydroxylabda-8(17), 13E-dien-19-oic acid(6) were isolated. The structures of the isolated compounds were established by means of NMR and MS analyses. Compound 1~6 were firstly isolated from this plant. Compound 1 is new natural products. Among them , compound 1 and 6 show anti- inflammatory activities.

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8

Perualila-Tan, Nolen Joy, Ziv Shkedy, Willem Talloen, Hinrich W. H. Göhlmann, Marijke Van Moerbeke, and Adetayo Kasim. "Weighted similarity-based clustering of chemical structures and bioactivity data in early drug discovery." Journal of Bioinformatics and Computational Biology 14, no. 04 (August 2016): 1650018. http://dx.doi.org/10.1142/s0219720016500189.

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The modern process of discovering candidate molecules in early drug discovery phase includes a wide range of approaches to extract vital information from the intersection of biology and chemistry. A typical strategy in compound selection involves compound clustering based on chemical similarity to obtain representative chemically diverse compounds (not incorporating potency information). In this paper, we propose an integrative clustering approach that makes use of both biological (compound efficacy) and chemical (structural features) data sources for the purpose of discovering a subset of compounds with aligned structural and biological properties. The datasets are integrated at the similarity level by assigning complementary weights to produce a weighted similarity matrix, serving as a generic input in any clustering algorithm. This new analysis work flow is semi-supervised method since, after the determination of clusters, a secondary analysis is performed wherein it finds differentially expressed genes associated to the derived integrated cluster(s) to further explain the compound-induced biological effects inside the cell. In this paper, datasets from two drug development oncology projects are used to illustrate the usefulness of the weighted similarity-based clustering approach to integrate multi-source high-dimensional information to aid drug discovery. Compounds that are structurally and biologically similar to the reference compounds are discovered using this proposed integrative approach.

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Yokosuka, Akihito, Atsushi Sekiguchi, and Yoshihiro Mimaki. "Chemical Constituents of the Leaves of Dracaena thalioides." Natural Product Communications 8, no. 3 (March 2013): 1934578X1300800. http://dx.doi.org/10.1177/1934578x1300800309.

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Two new furostanol bisdesmosides (1 and 2) and seven known compounds (3-9) were isolated from the leaves of Dracaena thalioides (Agavaceae). The structures of the new compounds were determined on the basis of spectroscopic data and the results of hydrolytic cleavage. The isolated compounds were evaluated for cytotoxic activity against HL-60 human promyelocytic leukemia cells. Compound 5, a glyceroglycolipid-related compound assigned as (2 S)-1- O-linoleoyl-3- O-β-D-galactopyranosylglycerol, was found to induce apoptotic cell death in HL-60 cells with an IC50 value of 25.8 μM.

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10

Chel Kwun, Young, Manzoor Ahmad Zahid, Waqas Nazeer, Ashaq Ali, Maqbool Ahmad, and Shin Min Kang. "On the zagreb polynomials of benzenoid systems." Open Physics 16, no. 1 (November 30, 2018): 734–40. http://dx.doi.org/10.1515/phys-2018-0092.

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AbstractTopological indices play significant role in determining properties of chemical compound. Algebraic polynomials help to compute topological indices of studied chemical compounds. Benzenoid systems are used mainly as an intermediate to make other chemicals. In this report we aim to compute Zagreb polynomials of zigzag, rhombic, triangular, hourglass and jagged-rectangle benzenoid systems.

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11

Nanni, Loris, Sheryl Brahnam, and Gianluca Maguolo. "Anatomical Therapeutic Chemical Classification (ATC) With Multi-Label Learners and Deep Features." International Journal of Natural Computing Research 9, no. 3 (July 2020): 16–29. http://dx.doi.org/10.4018/ijncr.2020070102.

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Automatic anatomical therapeutic chemical (ATC) classification predicts an unknown compound's therapeutic and chemical characteristics. Predicting the organs/systems an unidentified compound will act on has the potential of expediting drug development and research. That a given compound can affect multiple organs/systems makes automatic ATC classification a complex problem. In this paper, the authors experimentally develop a multi-label ensemble for ATC prediction. The proposed approach extracts a 1D feature vector based on a compound's chemical-chemical interaction and its structural and fingerprint similarities to other compounds, as defined by the ATC coding system. This 1D vector is reshaped into 2D matrices and fed into seven pre-trained convolutional neural networks (CNN). A bidirectional long short-term memory network (BiLSTM) is trained on the 1D vector. Features extracted from both deep learners are then trained on multi-label classifiers, with results fused. The best system proposed here is shown to outperform other methods reported in the literature.

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12

Roth, Dana L. "Web-Accessible Chemical Compound Information." Journal of Electronic Resources in Medical Libraries 5, no. 3 (September 4, 2008): 228–42. http://dx.doi.org/10.1080/15424060802222380.

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13

Shiratori, Masayuki. "Compound Technology on Chemical Sensor." Journal of the Society of Mechanical Engineers 103, no. 982 (2000): 622–23. http://dx.doi.org/10.1299/jsmemag.103.982_622.

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14

Ren, Jie, Yang-Guo Xie, Xing Wang, Shi-Kai Yan, Hui-Zi Jin, and Wei-Dong Zhang. "Chemical Constituents of Euonymus glabra." Natural Product Communications 10, no. 12 (December 2015): 1934578X1501001. http://dx.doi.org/10.1177/1934578x1501001222.

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One new phenolic compound (1) and one new flavan (2), together with eight known compounds (3–10) were isolated from the stems and twigs of Euonymus glabra Roxb. Their structures were elucidated mainly on the basis of 1D and 2D spectroscopic methods and circular dichroism analysis. In addition, compounds 1–10 were tested for their inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Compounds 1–5 and 7 exhibited moderate inhibitory activities with IC50 values ranged from 5.1 to 11.9 μM.

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15

HASHIMOTO, YUICHI. "Old and new chemical compound thalidomide.Expectation as lead chemical compounds for bioresponse modifier (BRM)." Kagaku To Seibutsu 32, no. 9 (1994): 604–8. http://dx.doi.org/10.1271/kagakutoseibutsu1962.32.604.

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16

Naveja, J. Jesús, Mariel P. Rico-Hidalgo, and José L. Medina-Franco. "Analysis of a large food chemical database: chemical space, diversity, and complexity." F1000Research 7 (July 3, 2018): 993. http://dx.doi.org/10.12688/f1000research.15440.1.

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Background: Food chemicals are a cornerstone in the food industry. However, its chemical diversity has been explored on a limited basis, for instance, previous analysis of food-related databases were done up to 2,200 molecules. The goal of this work was to quantify the chemical diversity of chemical compounds stored in FooDB, a database with nearly 24,000 food chemicals. Methods: The visual representation of the chemical space of FooDB was done with ChemMaps, a novel approach based on the concept of chemical satellites. The large food chemical database was profiled based on physicochemical properties, molecular complexity and scaffold content. The global diversity of FoodDB was characterized using Consensus Diversity Plots. Results: It was found that compounds in FooDB are very diverse in terms of properties and structure, with a large structural complexity. It was also found that one third of the food chemicals are acyclic molecules and ring-containing molecules are mostly monocyclic, with several scaffolds common to natural products in other databases. Conclusions: To the best of our knowledge, this is the first analysis of the chemical diversity and complexity of FooDB. This study represents a step further to the emerging field of “Food Informatics”. Future study should compare directly the chemical structures of the molecules in FooDB with other compound databases, for instance, drug-like databases and natural products collections.

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Aliev, I. I., S. Sh Ismailova, and M. H. Shakhbazov. "RESEARCH CHEMICAL INTERACTIONS IN THE CuTe–As2Te3 SYSTEM." Azerbaijan Chemical Journal, no. 1 (April 9, 2021): 67–71. http://dx.doi.org/10.32737/0005-2531-2021-1-67-71.

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By the methods of DTA, XRD, MSA, as well as by measuring the microhardness and determining the density of the alloys, the CuTe–As2Te3 system was studied and a phase diagram was constructed. The system state diagram is of the eutectic type and it is characterized by one chemical compound of Cu3As4Te9 composition. Compounds Cu3As4Te9 melts incongruently at 3200C. Solid solutions based on As2Te3 reaches 8 mol %, and based on CuTe solid solutions are practically not installed. Cu3As4Te9 and As2Te3 form an eutectic composition of 45 mol % As2Te3 and temperature 2650C. The results of X-ray phase analysis have shown that the Сu3As4Te9 compounds is crystallized in the tetragonal syngony with lattice parameters: a = 13.86, c = 18.05 Å, Z = 9, ρpyk. = 6.96 g/cm3, ρrent. = 7.06 g/cm3

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Ata, Athar, Nathan Mbong, Chad D. Iverson, and Radhika Samarasekera. "Minor Chemical Constituents of Vitex Pinnata." Natural Product Communications 4, no. 1 (January 2009): 1934578X0900400. http://dx.doi.org/10.1177/1934578x0900400102.

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From the bark of Vitex pinnata, one new iridoid glucoside, pinnatoside (1) and three known flavonoids, viscioside (2), apigenin (3), and luteolin (4), were isolated. Structures of these compounds were determined from NMR spectroscopic studies. Compound 1 exhibited modest antifungal activity against Candida albicans.

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Naveja, J. Jesús, Mariel P. Rico-Hidalgo, and José L. Medina-Franco. "Analysis of a large food chemical database: chemical space, diversity, and complexity." F1000Research 7 (August 10, 2018): 993. http://dx.doi.org/10.12688/f1000research.15440.2.

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Background: Food chemicals are a cornerstone in the food industry. However, its chemical diversity has been explored on a limited basis, for instance, previous analysis of food-related databases were done up to 2,200 molecules. The goal of this work was to quantify the chemical diversity of chemical compounds stored in FooDB, a database with nearly 24,000 food chemicals. Methods: The visual representation of the chemical space of FooDB was done with ChemMaps, a novel approach based on the concept of chemical satellites. The large food chemical database was profiled based on physicochemical properties, molecular complexity and scaffold content. The global diversity of FooDB was characterized using Consensus Diversity Plots. Results: It was found that compounds in FooDB are very diverse in terms of properties and structure, with a large structural complexity. It was also found that one third of the food chemicals are acyclic molecules and ring-containing molecules are mostly monocyclic, with several scaffolds common to natural products in other databases. Conclusions: To the best of our knowledge, this is the first analysis of the chemical diversity and complexity of FooDB. This study represents a step further to the emerging field of “Food Informatics”. Future study should compare directly the chemical structures of the molecules in FooDB with other compound databases, for instance, drug-like databases and natural products collections. An additional future direction of this work is to use the list of 3,228 polyphenolic compounds identified in this work to enhance the on-going polyphenol-protein interactome studies.

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Fathy, Hoda M., Mohamed I. Aboushoer, Fathallah M. Harraz, Abdallah A. Omar, Gilles Goetz, and Rafael Tabacchi. "Dolabellane Diterpenes from Cleome Droserifolia." Natural Product Communications 3, no. 9 (September 2008): 1934578X0800300. http://dx.doi.org/10.1177/1934578x0800300915.

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Three diterpenoid dolabellane esters were isolated from Cleome droserifolia. The chemical structures of the isolated compounds were determined by spectral as well as chemical methods. These dolabellanes (I, II and III) are ester derivatives of 3-hydroxy-3-methyl glutaric acid (3-HMGA). Compounds I and II have the second (3HMGA) carboxyl function free, while compound III is the methyl ester of compound I. This is the first report of the isolation of this class of compounds from the genus Cleome and is the first report of the isolation of compound III from a natural source. In addition, eight flavone derivatives were isolated.

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Słoczyńska, Karolina, Agnieszka Gunia-Krzyżak, Paulina Koczurkiewicz, Katarzyna Wójcik-Pszczoła, Dorota Żelaszczyk, Justyna Popiół, and Elżbieta Pękala. "Metabolic stability and its role in the discovery of new chemical entities." Acta Pharmaceutica 69, no. 3 (September 1, 2019): 345–61. http://dx.doi.org/10.2478/acph-2019-0024.

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Abstract Determination of metabolic profiles of new chemical entities is a key step in the process of drug discovery, since it influences pharmacokinetic characteristics of therapeutic compounds. One of the main challenges of medicinal chemistry is not only to design compounds demonstrating beneficial activity, but also molecules exhibiting favourable pharmacokinetic parameters. Chemical compounds can be divided into those which are metabolized relatively fast and those which undergo slow biotransformation. Rapid biotransformation reduces exposure to the maternal compound and may lead to the generation of active, non-active or toxic metabolites. In contrast, high metabolic stability may promote interactions between drugs and lead to parent compound toxicity. In the present paper, issues of compound metabolic stability will be discussed, with special emphasis on its significance, in vitro metabolic stability testing, dilemmas regarding in vitro-in vivo extrapolation of the results and some aspects relating to different preclinical species used in in vitro metabolic stability assessment of compounds.

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Karaket, Netiya, Kanyaratt Supaibulwatana, Supatsara Ounsuk, Valérie Bultel-Poncé, Van Cuong Pham, and Bernard Bodo. "Chemical and Bioactivity Evaluation of the Bark of Neonauclea purpurea." Natural Product Communications 7, no. 2 (February 2012): 1934578X1200700. http://dx.doi.org/10.1177/1934578x1200700208.

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Bioassay-guided fractionation of the MeOH extract from the stem bark of Neonauclea purpurea used in traditional medicine, resulted in the isolation of 2 indole alkaloids, cadambine (1) and α-dihydrocadambine (2), as well as a quinolic compound, 2,6-dimethoxy-1,4-benzoquinone (3). Antimalarial activity evaluation showed that compounds 2 and 3 exhibited mild in vitro antimalarial activity against Plasmodium falciparum, the chloroquine-resistant strain K1 with IC50 values of 6.6 and 11.3 μM, respectively. Compounds 1 and 2 showed no cytotoxicity to monkey (Vero) cells, but compound 3 showed weak cytotoxicity with an IC50 value of 1.19 μM.

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Schroeder, Grzegorz, and Joanna Kurczewska. "Chemistry for nanotechnology." Polish Journal of Chemical Technology 16, no. 1 (March 1, 2014): 70–74. http://dx.doi.org/10.2478/pjct-2014-0012.

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Abstract In recent years, the processing order during the synthesis of new chemical compounds has been redefined. Until now a chemist considered primarily receiving a new compound and only then searched for its potential application. The new philosophy of proceedings forces chemists to answer the question: what physical and chemical properties a new chemical compound must have, and what should be structured. After that it has to be planned how to get the compound including the defined budget. The compounds obtained by conventional chemical synthesis are then used to create new functional materials having the properties as scheduled. The paper presents the way of the proceedings from a molecular receptor to a new nanomaterial containing this receptor, so in other words from individual molecules to new material with specific and previously planned properties.

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Elhendawy, Mostafa A., Amira S. Wanas, Mohamed M. Radwan, Nabil A. Azzaz, ElShahat S. Toson, and Mahmoud A. ElSohly. "Chemical and Biological Studies of Cannabis sativa Roots." Medical Cannabis and Cannabinoids 1, no. 2 (December 4, 2018): 104–11. http://dx.doi.org/10.1159/000495582.

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The chemical study of Cannabis sativa roots led to the isolation and identification of 10 compounds. Their chemical structures were unambiguously established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry as friedelan-3-one (1), epifriedelanol (2), β-sitosterol (3), ergost-5-en-3-ol (4), methyl hexadecanoate (5), pentadecanoic acid (6), 10E-hexadecenoic acid (7), 4-hydroxy-3-methoxybenzaldehyde (8), β-sitosterol-β-D-glucoside (9) and p-coumaroyltyramine (10). Compounds 5–9 were reported for the first time from C. sativa roots. All the isolated compounds were tested for their antimicrobial activity. Compound 4 showed modest activity against Cryptococcus neoformans with an IC50 value of 13.7 μg/mL, while compound 10 displayed potent activity against Escherichia coli with an IC50 value of 0.8 μg/mL. A high-performance liquid chromatography method was developed and validated for the detection and quantification of p-coumaroyltyramine (10) in the extracts of different varieties of C. sativa roots.

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Rinne, J., T. Markkanen, T. M. Ruuskanen, T. Petäjä, P. Keronen, M. J. Tang, J. N. Crowley, Ü. Rannik, and T. Vesala. "Effect of chemical degradation on fluxes of reactive compounds." Atmospheric Chemistry and Physics Discussions 11, no. 12 (December 2, 2011): 31819–49. http://dx.doi.org/10.5194/acpd-11-31819-2011.

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Abstract. In the analyses of VOC fluxes measured above plant canopies, one usually assumes the flux above canopy to equal the emission at the surface. Thus one assumes the chemical degradation to be much slower than the turbulent transport. We used a stochastic Lagrangian transport model in which the chemical degradation was described as first order decay in order to study the effect of the chemical degradation on above canopy fluxes of chemically reactive species. With the model we explored the sensitivity of the ratio of the above canopy flux to the surface emission on several parameters such as chemical lifetime of the compound, friction velocity, stability, and canopy density. Our results show that friction velocity and chemical lifetime affected the loss during transport the most. The canopy density had a significant effect if the chemically reactive compound was emitted from the forest floor. We used the results of the simulations together with oxidant data measured during HUMPPA-COPEC-2010 campaign at a Scots pine site to estimate the effect of the chemistry on fluxes of three typical biogenic VOCs, isoprene, α-pinene, and β-caryophyllene. Of these, the chemical degradation had a~major effect on the fluxes of the most reactive species β-caryophyllene, while the fluxes of α-pinene were affected during nighttime. For these two compounds representing the mono- and sesquiterpenes groups, the effect of chemical degradation had also a significant diurnal cycle with the highest chemical loss at night. The different day and night time loss terms need to be accounted for, when measured fluxes of reactive compounds are used to reveal relations between primary emission and environmental parameters.

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Salazar Allen, Noris, Ana Isabel Santana, Nélida Gómez, Clementina Chung C, and Mahabir Prashad Gupta. "Identification of volatile compounds from three species of Cyathodium (Marchantiophyta: Cyathodiaceae) and Leiosporoceros dussii(Anthocerotophyta: Leiosporocerotaceae) from Panama, and C. foetidissimum from Costa Rica." Boletín de la Sociedad Argentina de Botánica 52, no. 2 (July 7, 2017): 357–70. http://dx.doi.org/10.31055/1851.2372.v52.n2.17451.

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Cyathodium is a thalloid marchantialean liverwort with five species reported for the Neotropics. Three species that occur in Panama (C. bischlerianum, C. spruceanum, C. cavernarum) and one from Costa Rica (C. foetidissimum) were studied chemically. Female and male plants of the dioecious C. spruceanum were very similar in their chemical composition except for two compounds that were found only in female plants. All samples of C. spruceanum and C. bischlerianum contained, in less than three percent, the sesquiterpenes germacrene D and bicyclogermacrene. The presence of these compounds suggests a close affinity between these two species. Cyathodium bischlerianum contained mainly aromatic monoterpenes with nerolidol as the main compound. Cyathodium cavernarum also had a very distinct chemical composition with an octane derivative as its major compound. Indole compounds were found only in C. foetidissimum. The presence of these compounds in plants from Costa Rica and Tahiti suggests that they could be considered as potential chemosystematic markers for the species. Based on their chemical composition there is a clear distinction between the four species of Cyathodium studied. The chemistry of these species supports previous morphological and genetic studies. Only two compounds could be identified in Leiosporoceros dussii. There is a need for additional genetic and chemical studies on neotropical Cyathodium and Leiosporoceros. Key

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Gunawan, Ramdhan, and Asep Bayu Dani Nandiyanto. "How to Read and Interpret 1H-NMR and 13C-NMR Spectrums." Indonesian Journal of Science and Technology 6, no. 2 (May 15, 2021): 267–98. http://dx.doi.org/10.17509/ijost.v6i2.34189.

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Nuclear magnetic resonance spectroscopy or NMR is a chemical instrument that can be used to evaluate the structure of a chemical compound other than FTIR, GC-MS, and HPLC. NMR spectroscopy commonly used for compound analysis is 1H-NMR and 13C-NMR. Techniques can be used to determine the structure conformation, the number of protons, and the number of carbons in the structure of a chemical compound. So far, there have been many publications related to the use of this spectroscopic technique. However, the steps in reading and interpreting the spectra of both 1H-NMR and 13C-NMR are not described in detail. Thus, in this paper, we described the steps in reading and interpreting the 1H-NMR and 13C-NMR spectra based on the level of difficulties: (1) simple compounds, (2) fairly complex compounds, (3) more complex compounds, and (4) very complex compounds.

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Kosmulalage, Kalhari S., Shamsulhaq Zahid, Chibuike C. Udenigwe, Sarfraz Akhtar, Athar Ata, and Radhika Samarasekera. "Glutathione S-Transferase, Acetylcholinesterase Inhibitory and Antibacterial Activities of Chemical Constituents of Barleria prionitis." Zeitschrift für Naturforschung B 62, no. 4 (April 1, 2007): 580–86. http://dx.doi.org/10.1515/znb-2007-0417.

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Phytochemical studies on the ethanolic extract of Barleria prionitis of Sri Lankan origin have resulted in the isolation of a new compound, balarenone (1), along with three known compounds, pipataline (2), lupeol (3) and 13,14-seco-stigmasta-5,14-diene-3-α-ol (4). The structures of 1 - 4 were elucidated with the aid of extensive NMR spectroscopic studies. Compounds 1 - 4 showed moderate inhibitory activity against glutathione S-transferase (GST) and acetylcholinesterase (AChE). Compounds 1, 2 and 4 also exhibited antibacterial activity against Bacillus cereus and Pseudomonas aeruginosa (25 μg/disk). Three different derivatives of compound (2), 7,8-epoxypipataline (5), 8- amino-7-hydroxypipataline (6) and 7,8-dibromopipataline (7) were synthesized to evaluate them for GST and AChE inhibitory activities. Household microwave radiations were used to synthesize compound (6). Among all tested compounds, 8-amino-7-hydroxypipataline (6) exhibited a significant AChE inhibitory activity with an IC50 value of 36.8 μM.

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Hussain, Javid, Nausheen Bukhari, Hidayat Hussain, Najeeb U. Rehman, and Syed Murtaza Hussain. "Chemical Constituents of Nepeta Distans." Natural Product Communications 5, no. 11 (November 2010): 1934578X1000501. http://dx.doi.org/10.1177/1934578x1000501117.

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Phytochemical investigation of Nepeta distans Raul resulted in the isolation of a new phenolic compound, nepatanol (1), and eight known compounds, markhamioside F, netidiol, nepedinol, thymoquinone, eugenol, oleanolic acid, ursolic acid, and β-sitosterol, which have been isolated for the first time from this source. Structures of all the isolates were established on the basis of MS, and 1D and 2D NMR spectral data and by comparison with reported data.

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Usman, Usman, Nunuk Hariani Soekamto, Muhammad Natsir, and Maulidiyah Maulidiyah. "Isolation of Natural Derivated Steroidal from Bark Stem of Melochia umbellata (Houtt) Stapf var. degrabrata K." Asian Journal of Chemistry 32, no. 4 (February 25, 2020): 765–70. http://dx.doi.org/10.14233/ajchem.2020.22414.

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Exploration of the natural product as pharmaceutical drug widely discover continuously for human life. The unique chemical compounds have been explored from bark stem of Melochia Umbellata (Houtt) Stapf var. degrabrata K. (M. umbellata) which is obtained from South Sulawesi, Indonesia. We discovered two group compounds isolated namely stigmasta-5,22-dien-3-β-ol (1) and stigmasta-5,22-dien-on (2), from n-hexane and chloroform extracts. The chemical structure of compounds 1 and 2 were identified based on IR spectroscopic, 1H NMR and 13C NMR and compared spectra data with data of compounds by other researchers. Compounds 1 and 2 are evaluated of their toxicity activity against shrimp larvae (Artemia salina) shows that the compound 1 shows weak toxicity activities against Artemia salina with LC50 value of 548.48 μg/mL, meanwhile the compound 2 exhibits a high inhibitory by LC50 value of 410.81 μg/mL. Based on this study, we suggest that the compound 2 has good bioactivity compared with compound 1.

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Miranda-Quintana, Ramón Alain, and Paul W. Ayers. "Interpolating Hamiltonians in chemical compound space." International Journal of Quantum Chemistry 117, no. 14 (April 5, 2017): e25384. http://dx.doi.org/10.1002/qua.25384.

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Ata, Athar, Chibuike C. Udenigwe, Wadim Matochko, Paul Holloway, Michael O. Eze, and Peter N. Uzoegwu. "Chemical Constituents of Nauclea latifolia and their Anti-GST and Anti-Fungal Activities." Natural Product Communications 4, no. 9 (September 2009): 1934578X0900400. http://dx.doi.org/10.1177/1934578x0900400905.

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The crude ethanolic extract of Nauclea latifolia yielded five known compounds, strictosamide (1), naucleamides A (2), naucleamide F (3), quinovic acid-3-O-β-rhamnosylpyranoside (4), and quinovic acid 3-O-β-fucosylpyranoside (5). Microbial reactions, using a whole cell culture of Rhizopus circinans on compound (1), yielded three analogues, 10-hydroxystrictosamide (6), 10-4bT-glucosyloxyvincoside lactam (7) and 16,17-dihydro-10-β-glucosyloxyvincoside lactam (8). Compounds 1-8 were identified with the aid of extensive NMR spectral studies. Compound 8 was found to be a new metabolite. Compounds 1-8 exhibited different levels of anti-GST and antifungal activities.

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Lee, Sang-Hyeok, Sangjin Ahn, and Mi-hyun Kim. "Comparing a Query Compound with Drug Target Classes Using 3D-Chemical Similarity." International Journal of Molecular Sciences 21, no. 12 (June 12, 2020): 4208. http://dx.doi.org/10.3390/ijms21124208.

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3D similarity is useful in predicting the profiles of unprecedented molecular frameworks that are 2D dissimilar to known compounds. When comparing pairs of compounds, 3D similarity of the pairs depends on conformational sampling, the alignment method, the chosen descriptors, and the similarity coefficients. In addition to these four factors, 3D chemocentric target prediction of an unknown compound requires compound–target associations, which replace compound-to-compound comparisons with compound-to-target comparisons. In this study, quantitative comparison of query compounds to target classes (one-to-group) was achieved via two types of 3D similarity distributions for the respective target class with parameter optimization for the fitting models: (1) maximum likelihood (ML) estimation of queries, and (2) the Gaussian mixture model (GMM) of target classes. While Jaccard–Tanimoto similarity of query-to-ligand pairs with 3D structures (sampled multi-conformers) can be transformed into query distribution using ML estimation, the ligand pair similarity within each target class can be transformed into a representative distribution of a target class through GMM, which is hyperparameterized via the expectation–maximization (EM) algorithm. To quantify the discriminativeness of a query ligand against target classes, the Kullback–Leibler (K–L) divergence of each query was calculated and compared between targets. 3D similarity-based K–L divergence together with the probability and the feasibility index, (Fm), showed discriminative power with regard to some query–class associations. The K–L divergence of 3D similarity distributions can be an additional method for (1) the rank of the 3D similarity score or (2) the p-value of one 3D similarity distribution to predict the target of unprecedented drug scaffolds.

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Karima, Rizka. "Ekstraksi dan Analisis Kimia Daun Gulinggang (Cassia alata Linn.) dengan Pelarut Air dan Etanol (The Extraction and Chemical Analysis of Gulinggang Leaves (Cassia alata Linn.) using Water and Ethanol as Solvents)." Jurnal Riset Industri Hasil Hutan 9, no. 1 (September 14, 2017): 1–8. http://dx.doi.org/10.24111/jrihh.v9i1.2948.

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Gulinggang (Cassia alata Linn.) is a shrub that was used as a natural remedy by Japanese. However, the main compound of gulinggang in Kalimantan has not been identified. The purpose of the research were to identify its chemical and phytochemical compounds, as well as to determine the suitable methods and solvents for gulinggang extraction. The research used two methods of extraction: soxhlet apparatus and maceration; and three kinds of solution: water, ethanol 96% and water-ethanol (1:1). Gulinggang leaves extract was tested the chemical and phytochemical contents to identify the secondary metabolites compounds. The most dominant chemical compound found in the extracts is Methoxy, phenyl-oxime. The extraction method that gives maximum results on secondary metabolites of phytochemical compound was maceration methods using 96% ethanol. The result of secondary metabolites of phytochemical compound were alkaloids 0,04%; saponins 1,79%; tannins 0,10%; phenolics 5,12%; flavonoids as quercetin 0,09%; triterpenoid 0,05%; and steroids 1,02%.Keywords : Cassia alata Linn., extraction, gulinggang, phytochemical

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35

De Araújo, Mônica Regina Silva, João Carlos Da Costa Assunção, Ivana Nogueira Fernandes Dantas, Letícia Veras Costa-Lotufo, and Francisco José Queiroz Monte. "Chemical Constituents of Ximenia Americana." Natural Product Communications 3, no. 6 (June 2008): 1934578X0800300. http://dx.doi.org/10.1177/1934578x0800300605.

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Two steroids (1 and 2), five pentacyclic triperpenoids (3–7) and a new furanosesquiterpene (8) were isolated from the stems of Ximenia americana, family Olacaceae. The structures of the compounds were established by spectral data; two-dimensional NMR spectroscopy has been used to assign all 1H and 13C chemical shifts of 8. Compound 8 did not inhibit the growth of HL-60 (human leukemia), HTC-8 (human colon), and MDA-MB-435 (human breast cancer) cell lines.

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Chen, Dan, Peng Zhang, Tong Liu, Xiu-Fang Wang, Zhao-Xia Li, Wei Li, and Feng-Long Wang. "Insecticidal Activities of Chloramphenicol Derivatives Isolated from a Marine Alga-Derived Endophytic Fungus, Acremonium vitellinum, against the Cotton Bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)." Molecules 23, no. 11 (November 16, 2018): 2995. http://dx.doi.org/10.3390/molecules23112995.

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A great deal of attention has been focused on the secondary metabolites produced by marine endophytic fungi, which can be better alternatives to chemicals, such as biopesticides, for control of polyphagous pests. On the basis of its novel biocontrol attributes, chemical investigation of a marine alga-derived endophytic fungus, Acremonium vitellinum, resulted in the isolation of three chloramphenicol derivatives (compounds 1–3). Their chemical structures were elucidated by detailed analysis of their nuclear magnetic resonance spectra, high-resolution electrospray ionization mass spectrometry, and by comparison with the data available in the literature. In this paper, compound 2 was firstly reported as the natural origin of these fungal secondary metabolites. The insecticidal activities of compounds 1–3 against the cotton bollworm, Helicoverpa armigera, were evaluated. The natural compound 2 presented considerable activity against H. armigera, with an LC50 value of 0.56 ± 0.03 mg/mL (compared to matrine with an LC50 value of 0.24 ± 0.01 mg/mL). Transcriptome sequencing was used to evaluate the molecular mechanism of the insecticidal activities. The results presented in this study should be useful for developing compound 2 as a novel, ecofriendly and safe biopesticide.

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Kunig, Verena, Marco Potowski, Anne Gohla, and Andreas Brunschweiger. "DNA-encoded libraries – an efficient small molecule discovery technology for the biomedical sciences." Biological Chemistry 399, no. 7 (June 27, 2018): 691–710. http://dx.doi.org/10.1515/hsz-2018-0119.

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Abstract DNA-encoded compound libraries are a highly attractive technology for the discovery of small molecule protein ligands. These compound collections consist of small molecules covalently connected to individual DNA sequences carrying readable information about the compound structure. DNA-tagging allows for efficient synthesis, handling and interrogation of vast numbers of chemically synthesized, drug-like compounds. They are screened on proteins by an efficient, generic assay based on Darwinian principles of selection. To date, selection of DNA-encoded libraries allowed for the identification of numerous bioactive compounds. Some of these compounds uncovered hitherto unknown allosteric binding sites on target proteins; several compounds proved their value as chemical biology probes unraveling complex biology; and the first examples of clinical candidates that trace their ancestry to a DNA-encoded library were reported. Thus, DNA-encoded libraries proved their value for the biomedical sciences as a generic technology for the identification of bioactive drug-like molecules numerous times. However, large scale experiments showed that even the selection of billions of compounds failed to deliver bioactive compounds for the majority of proteins in an unbiased panel of target proteins. This raises the question of compound library design.

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Sameut, Asmaâ, Sarah Yasmine Zanndouche, Chaimaa Boumaza, Chaima Dikes, and Borhane Eddine Cherif Ziani. "Chemical Synthesis and Hemi-Synthesis of Novel Benzimidazole Derivatives Using Microwave-Assisted Process: Chemical Characterization, Bioactivities and Molecular Docking." Chemistry Proceedings 3, no. 1 (November 14, 2020): 71. http://dx.doi.org/10.3390/ecsoc-24-08306.

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Benzimidazole derivatives represent a class of heterocyclic compounds that exhibit a wide range of pharmaceutical properties. The present study aimed to investigate the in-vitro antioxidant and antimicrobial activities of newly synthesized benzimidazole derivatives. Compound 1b (2-(1H-1,3-benzodiazol-2-yl) phenol) was synthesized by reacting o-phenylenediamine (OPA) with chemical salicylaldehyde, while compounds 2b (2-(2-[(1E)-2-phenylethenyl]-1H-1,3-benzodiazole) and 3b (2-[(1E)-2,6-dimethylhepta-1,5-dien-1-yl]-1H-1,3-benzodiazole) were obtained through a hemi-synthesis process of, respectively, the cinnamon (cinnamaldehyde, 90.54%) and lemongrass (cis-citral, 43.9%) essential oils previously characterized by GC/MS. Compounds 4b (2-phenyl-1H-benzimidazole) and 5b (5-(1H-benzimidazol-2-yl)benzene-1,2,3-triol) were synthesized with a click chemistry method by reacting the OPA with benzoic acid and gallic acid directly in ethanol under microwave irradiation (MW) at 400 MHz. The structure/purity of the synthesized compounds was clarified by spectroscopy, ATR-FTIR and NMR 1H. Compounds 1b–5b were screened for their antioxidant activity by using four complementary in-vitro assays: DPPH scavenging activity, ferric ion reducing power, β-carotene bleaching inhibition, and Thiobarbituric Acid Reactive Substance Assay (TBARS) formation inhibition. All the tested compounds showed antioxidant potential, with varying performance. Antimicrobial activity was investigated against American Type Culture Collection (ATCC) strains (three Gram- bacteria: Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa; one Gram+ bacteria: Staphylococcus aureus, and one yeast strain: Candida albicans) through the determination of the Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) by using the microdilution method and rapid colorimetric test of p-iodonitrotetrazolium chloride (INT). Compound 5b exhibited the highest potential, especially against S. aureus (MIC = 0.156 mg·mL−1) followed by S. typhi and C. albicans (MIC = 0.3125 mg·mL−1) and then by E. coli and P. aeruginosa. Compound 1b also showed great potential against S. aureus and C. albicans (MIC ˂ 0.3125 mg·mL−1), followed by E. coli and S. typhi (MIC = 0.3125 mg·mL−1) and P. aeruginosa (MIC = 0.625 mg·mL−1). Further molecular docking was conducted using AutoDock Vina 1.1.2 software on S. aureus thymidylate kinase (TMK) protein to highlight the structure–activity relationship of the potent molecules.

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Le, Dung Thi Kim, Hao Xuan Bui, Tuyet Thi Anh Nguyen, Tuyen Nguyen Kim Pham, and Huy Thuc Duong. "Chemical constituents of Euphorbia tirucalli L." Science and Technology Development Journal - Natural Sciences 2, no. 5 (July 2, 2019): 76–82. http://dx.doi.org/10.32508/stdjns.v2i5.781.

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Euphorbia tirucalli has not been chemically studied much in Vietnam. This research described the isolation and elucidation of compounds isolated from the plant collected in Binh Thuan. Multiple chromatographic methods were applied, including normal phase silica gel column chromatography and thin-layer chromatography. Seven compounds were isolated and their chemical structures were elucidated by spectroscopic analysis as well as comparing their data with the ones in the literature. They are arjunolic acid (1), eriodictyol (2), quercitrin (3), afzelin (4), scopoletin (5), 3,3′,4- trimethylellagic acid (6), and gallic acid (7). Among them, compound 1 a major component was isolated for the first time in Euphorbia genus, while three compounds 2, 4, and 5 were isolated from this species for the first time.

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Tran, Trong D., Steven M. Ogbourne, Peter R. Brooks, Norberto Sánchez-Cruz, José L. Medina-Franco, and Ronald J. Quinn. "Lessons from Exploring Chemical Space and Chemical Diversity of Propolis Components." International Journal of Molecular Sciences 21, no. 14 (July 15, 2020): 4988. http://dx.doi.org/10.3390/ijms21144988.

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Propolis is a natural resinous material produced by bees and has been used in folk medicines since ancient times. Due to it possessing a broad spectrum of biological activities, it has gained significant scientific and commercial interest over the last two decades. As a result of searching 122 publications reported up to the end of 2019, we assembled a unique compound database consisting of 578 components isolated from both honey bee propolis and stingless bee propolis, and analyzed the chemical space and chemical diversity of these compounds. The results demonstrated that both honey bee propolis and stingless bee propolis are valuable sources for pharmaceutical and nutraceutical development.

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Liu, Yun, Aysha Siddiqa, Yu-Ming Chu, Muhammad Azam, Muhammad Asim Raza Basra, and Abaid Ur Rehman Virk. "Irregularity Measures for Benzene Ring Embedded in P-Type Surface." Mathematical Problems in Engineering 2020 (August 26, 2020): 1–13. http://dx.doi.org/10.1155/2020/2462530.

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A topological index is an important tool in predicting physicochemical properties of a chemical compound. Topological indices help us to assign a single number to a chemical compound. Drugs and other chemical compounds are frequently demonstrated as different polygonal shapes, trees, graphs, etc. In this paper, we will compute irregularity indices for the benzene ring embedded in a P-type surface BRp and the simple bounded dual of the benzene ring embedded in a P-type surface SBRp.

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Szajdak, Lech W., Jerzy Lipiec, Anna Siczek, Artur Nosalewicz, and Urszula Majewska. "Leaching Kinetics of Atrazine and Inorganic Chemicals in Tilled and Orchard Soils." International Agrophysics 28, no. 2 (April 1, 2014): 231–37. http://dx.doi.org/10.2478/intag-2014-0012.

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Abstract The aim of this study was to verify first-order kinetic reaction rate model performance in predicting of leaching of atrazine and inorganic compounds (K+1, Fe+3, Mg+2, Mn+2, NH4 +, NO3 - and PO4 -3) from tilled and orchard silty loam soils. This model provided an excellent fit to the experimental concentration changes of the compounds vs. time data during leaching. Calculated values of the first-order reaction rate constants for the changes of all chemicals were from 3.8 to 19.0 times higher in orchard than in tilled soil. Higher first-order reaction constants for orchard than tilled soil correspond with both higher total porosity and contribution of biological pores in the former. The first order reaction constants for the leaching of chemical compounds enables prediction of the actual compound concentration and the interactions between compound and soil as affected by management system. The study demonstrates the effectiveness of simultaneous chemical and physical analyses as a tool for the understanding of leaching in variously managed soils.

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43

Pei, Yi, Cong Shi, Jiang Li Nie, Ying Mei Han, and Dong Wang. "Studies on Chemical Constituents of the Baphicacanthus cusia (Nees) Bremek Root." Advanced Materials Research 550-553 (July 2012): 1759–62. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.1759.

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Objective: Studies on the chemical constituents of the Baphicacanthus plants, Baphicacanthus cusia (Nees) Bremek root. Methods: Using Column chromatography to separation and purification. Identify the compounds structures through the Physicochemical properties and spectral analysis methods. Result: Isolated 9 compounds from the Baphicacanthus cusia (Nees) Bremek roots. They were identified as Stigmasterol-3-O-β-D–glucoside(I), Spinasterol-3-O-β-D– glucoside(Ⅱ),2-(3,4-dihydroxyphenylacetic phenylethyl)]-3O-α-L-rhamnosyl-(1 → 4)-(4-O-caffeoyl)-β-D-pyran-glucosidase(III), Lupeol(Ⅳ), Indigo(Ⅴ), Indirubin (VI), Sucrose (Ⅶ), Adenosine (VIII), β-sitosterol(IX). Among them, compound I and compound II are compounds that at the first time isolated from this plant.

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Rehman, Najeeb Ur, Hidayat Hussain, Muhammaed Khiat, Husain Yar Khan, Ghulam Abbas, Ivan R. Green, and Ahmed Al-Harrasi. "Bioactive chemical constituents from the resin of Aloe vera." Zeitschrift für Naturforschung B 72, no. 12 (December 20, 2017): 955–58. http://dx.doi.org/10.1515/znb-2017-0117.

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AbstractBioassay-guided fractionation of Aloe vera (L.) Burm.f. resulted in the isolation and characterization of one new C-glucosyl chromone, 7-methoxy-6′-O-coumaroylaloesin (1), along with the known dihydroisocoumarin feralolide (2). The structure of 1 was elucidated on the basis of 1D, 2D-NMR, and mass spectrometry. Both compounds 1 and 2 were tested for their effects on the growth of cancer cells in culture and it was observed that unlike compound 1, compound 2 displayed concentration-dependent antiproliferative effects on breast cancer cells (MDA-MB-231) and ovarian cancer cells (SKOV-3). Additionally, only feralolide (2) demonstrated good urease, weak α-glucosidase enzyme inhibition, and weak antioxidant effects.

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Godjevac, Dejan, Vlatka Vajs, Slobodan Milosavljevic, Boban Djordjevic, Gordana Zdunic, and Vele Tesevic. "Chemical composition of white currant seed extract." Journal of the Serbian Chemical Society 76, no. 11 (2011): 1465–70. http://dx.doi.org/10.2298/jsc110617132g.

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From the seeds of white currant (Ribes rubrum, cv. White Champagne), a new sesquiterpenoid glucoside (1) was isolated, along with two known compounds: dihydrophaseic acid 3?-O-?-Dglucopyranoside (2), and 3-carboxymethyl-indole-1-N-?-Dglucopyranoside (3). The structure of the new compound was identified as dihydrophaseic acid 3?-O-?-D-glucopyranosyl-1,6-?-D-glucopyranoside, based on extensive NMR and MS spectral studies.

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Prasanna, M. D., Jiri Vondrasek, Alexander Wlodawer, H. Rodriguez, and T. N. Bhat. "Chemical compound navigator: A web-based chem-BLAST, chemical taxonomy-based search engine for browsing compounds." Proteins: Structure, Function, and Bioinformatics 63, no. 4 (February 28, 2006): 907–17. http://dx.doi.org/10.1002/prot.20914.

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Luo, Yong Ming, Hua Liu, and Xiao Ying Yin. "Chemical Constituents and Bioactivity of Chloranthus fortunei." Advanced Materials Research 746 (August 2013): 28–30. http://dx.doi.org/10.4028/www.scientific.net/amr.746.28.

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From Chloranthus fortunei, A new sesquiterpene lactones, fortuniolide A (1) were isolated, together with five known compounds, shizukaol B (2), and C (3) lasianthuslactone A(4), β-sitosterol (5) and 3,4-dihydroxybenzoic acid (6). The structures of the isolated compounds were established by means of NMR and MS analyses. These compounds were firstly isolated from this plant. Compound 1 is new natural products and have inhibitory activities on the release of β-glucuronidase from rat PMNs induced by PAF.

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STRIZHAK, PETER E. "APPLICATION OF CHEMICAL CHAOS TO ANALYTICAL CHEMISTRY." Advances in Complex Systems 06, no. 01 (March 2003): 137–53. http://dx.doi.org/10.1142/s021952590300075x.

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A simple theoretical consideration of the possibility of using deterministic chaos for a quantitative determination of trace amounts of chemical compounds is analyzed in terms of return maps. This allows the development of a general approach to find a calibration plot for a chemical compound determination, i.e. to find a one-to-one correspondence between a measured value and the concentration of a substance to be determined. As experimental verification of these theoretical results, we present a study of the effect of copper (II) ions on the transient chaotic regime in the BZ reaction catalyzed by ferroin in batch as well as of the effect of vanadium (IV) on the deterministic chaotic regime in the BZ reaction catalyzed by ferroin in a CSTR. These studies show that it is possible to quantify the response of transient chaotic regimes to chemical compounds, i.e. to construct a calibration plot for chemical compound determination using their effect on the chaotic dynamics in the BZ reaction. Moreover, these studies shown that vanadium (IV) affects the chaotic regimes at concentration levels of the order of 10-12 g/mL , which gives the best detection limit for the kinetic methods of trace analysis.

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Kiem, Phan Van, Nguyen Xuan Cuong, Nguyen Xuan Nhiem, Dan Thi Thuy Hang, Nguyen Hoai Nam, Ninh Khac Ban, Chau Van Minh, Zhou Bing, Hae Dong Jang, and Young Ho Kim. "Chemical Constituents and Antioxidant Activity of Ficus callosa." Natural Product Communications 6, no. 2 (February 2011): 1934578X1100600. http://dx.doi.org/10.1177/1934578x1100600201.

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One new megastigmane glycoside, ficalloside (1), and eleven known compounds, were isolated from methanol extract of Ficus callosa leaves by repeated column chromatography. Their structures were established on the basis of spectral and chemical evidence. The antioxidant activities of these compounds were measured using the oxygen radical absorbance capacity (ORAC) assay. Compound 8 exhibited potent antioxidant activity of 10.6 μM trolox equivalents at the concentration of 2 μM. At this concentration, compounds 4-7 and 9-12 showed significant antioxidant activity with ranging of 2.1~6.1 μM trolox equivalents.

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Gordo, Joana, Patrícia Máximo, Eurico Cabrita, Ana Lourenço, Abel Oliva, Joana Almeida, Mariana Filipe, et al. "Thymus mastichina: Chemical Constituents and their Anti-Cancer Activity." Natural Product Communications 7, no. 11 (November 2012): 1934578X1200701. http://dx.doi.org/10.1177/1934578x1200701120.

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The cytotoxicity-guided study of the dichloromethane and ethanol extracts of Thymus mastichna L. using the HCT colon cancer cell line allowed the identification of nine compounds, sakuranetin (1), sterubin (2), oleanolic acid (3), ursolic acid (4), lutein (5), β-sitosterol (6), rosmarinic acid (7), 6-hydroxyluteolin-7- O-β-glucopyranoside (8), and 6-hydroxyapigenin-7- O-β-glucopyranoside (9). All compounds were tested for their cytotoxicity against the HCT colon cancer cell line. Compound 4 showed cytotoxicity with GI50 value of 6.8 μg/mL. A fraction composed of a mixture (1:1) of triterpenoid acids 3 and 4 displayed improved cytotoxicity with a GI50 of 2.8 μg/mL suggesting a synergistic behavior. This is the first report on the chemical constituents of Thymus mastichna L. based on structural assignments by spectroscopic analysis. The presence of these constituents identified by colon cancer cytotoxicity-guided activity indicates that extracts of T. mastichna L. may have a protective effect against colon cancers.

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Journal articles on the topic 'Chemical compound'

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