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Journal articles on the topic 'C17-c25'

Author: Grafiati

Published: 4 June 2021

Last updated: 13 February 2022

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1

Siaut, Magali, Cécile Zaros, Emilie Levivier, Maria-Laura Ferri, Magali Court, Michel Werner, Isabelle Callebaut, Pierre Thuriaux, André Sentenac, and Christine Conesa. "An Rpb4/Rpb7-Like Complex in Yeast RNA Polymerase III Contains the Orthologue of Mammalian CGRP-RCP." Molecular and Cellular Biology 23, no. 1 (January 1, 2003): 195–205. http://dx.doi.org/10.1128/mcb.23.1.195-205.2003.

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ABSTRACT The essential C17 subunit of yeast RNA polymerase (Pol) III interacts with Brf1, a component of TFIIIB, suggesting a role for C17 in the initiation step of transcription. The protein sequence of C17 (encoded by RPC17) is conserved from yeasts to humans. However, mammalian homologues of C17 (named CGRP-RCP) are known to be involved in a signal transduction pathway related to G protein-coupled receptors, not in transcription. In the present work, we first establish that human CGRP-RCP is the genuine orthologue of C17. CGRP-RCP was found to functionally replace C17 in Δrpc17 yeast cells; the purified mutant Pol III contained CGRP-RCP and had a decreased specific activity but initiated faithfully. Furthermore, CGRP-RCP was identified by mass spectrometry in a highly purified human Pol III preparation. These results suggest that CGRP-RCP has a dual function in mammals. Next, we demonstrate by genetic and biochemical approaches that C17 forms with C25 (encoded by RPC25) a heterodimer akin to Rpb4/Rpb7 in Pol II. C17 and C25 were found to interact genetically in suppression screens and physically in coimmunopurification and two-hybrid experiments. Sequence analysis and molecular modeling indicated that the C17/C25 heterodimer likely adopts a structure similar to that of the archaeal RpoE/RpoF counterpart of the Rpb4/Rpb7 complex. These RNA polymerase subunits appear to have evolved to meet the distinct requirements of the multiple forms of RNA polymerases.

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2

Yadav, J. S., K. Bhaskar Reddy, and G. Sabitha. "Stereoconvergent synthesis of C1–C17 and C18–C25 fragments of bafilomycin A1." Tetrahedron 64, no. 8 (February 2008): 1971–82. http://dx.doi.org/10.1016/j.tet.2007.11.091.

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3

Zarnowski, Robert, Teresa Lewicka, and Stanislaw J. Pietr. "Production and Secretion of 5-n-Alkylresorcinols by Fusarium culmorum." Zeitschrift für Naturforschung C 55, no. 9-10 (October 1, 2000): 846–48. http://dx.doi.org/10.1515/znc-2000-9-1030.

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Abstract Fusarium culmorum F1 was found to produce and secrete into the culture medium several of 5-n-alkylresorcinols. The amount of resorcinolic lipids was 5.3 μg/g and 0.9 μg/l in mycelium and in post-culture liquid, respectively. First of all F. culmorum F1 produces saturated homologues with C15 to C25 side chains. The extract from the medium contained only homologues with shorter carbon chains (C13 to C17).

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4

Zelle, Robert E., Michael P. DeNinno, Harold G. Selnick, and Samuel J. Danishefsky. "A systematic degradation of zincophorin: a stereoselective synthesis of the C17-C25 fragment." Journal of Organic Chemistry 51, no. 25 (December 1986): 5032–36. http://dx.doi.org/10.1021/jo00375a060.

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5

Zarnowski, Robert, and Arkadiusz Kozubek. "Alkylresorcinol Homologs in Pisum sativum L. Varieties." Zeitschrift für Naturforschung C 54, no. 1-2 (February 1, 1999): 44–48. http://dx.doi.org/10.1515/znc-1999-1-208.

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Acetone extracts from the seeds of Pisum sativum L. sensu lato (Leguminoseae) separated by thin layer chromatography revealed the occurrence of hands with chromatographic mobility and color reaction with Fast Blue B characteristic for 1,3-dihydroxy-5-alkyIbenzenes. These polyketide metabolites have been isolated and identified by Spectroscopic means. The occurrence of homologous series of saturated (approximately 70%) and enoic (mono and diunsaturated) homologs with chain length of C15 to C25 has been revealed with C17 as the main homolog

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6

Fleury, Etienne, Geoffroy Sorin, Elise Prost, Ange Pancrazi, François Sautel, Georges Massiot, Marie-Isabelle Lannou, and Janick Ardisson. "Relative Stereochemical Determination and Synthesis of the C17–C25 δ-Lactone Fragment of Hemicalide." Journal of Organic Chemistry 78, no. 3 (January 23, 2013): 855–64. http://dx.doi.org/10.1021/jo302440a.

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7

Sawant, Kailas B., Fei Ding, and Michael P. Jennings. "Synthesis of the C17–C25 subunit of lasonolide A utilizing a Tsuchihashi–Yamamoto type rearrangement." Tetrahedron Letters 48, no. 30 (July 2007): 5177–80. http://dx.doi.org/10.1016/j.tetlet.2007.05.160.

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8

Zhang, Xingwang, Ping-Lin Li, Guo-Fei Qin, Shengying Li, Nicole de Voogd, Xu-Li Tang, and Guo-Qiang Li. "Isolation and Absolute Configurations of Diversiform C17, C21 and C25 Terpenoids from the Marine Sponge Cacospongia sp." Marine Drugs 17, no. 1 (December 28, 2018): 14. http://dx.doi.org/10.3390/md17010014.

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Chemical investigation of MeOH extract of a South China Sea sponge Cacospongia sp. yielded 15 terpenoids belonging to three different skeleton-types, including the unusual C17 γ-lactone norditerpenoids (1–3), the rare C21 pyridine meroterpenoid (7), and the notable C25 manoalide-type sesterterpenoids (4–6, 8–10). Compounds 1–5 were initially obtained as enantiomers, and were further separated to be optically pure compounds (1a, 1b, 2a, 2b, 3a-r, 3b-r, 4a, 4b, 5a and 5b) by chiral HPLC, with a LiAlH4 reduction aid for 3. Compounds 3a/3b (a pair of inseparable enantiomers), 4a, 5a, 6, and 7 were identified as new compounds, while 1a/1b and 2a/2b were obtained from a natural source and were determined for their absolute configurations for the first time. This is also the first time to encounter enantiomers of the well-known manoalide-type sesterterpenoids from nature. The structures with absolute configurations of the new compounds were unambiguously determined by comprehensive methods including HR-ESI-MS and NMR data analysis, optical rotation comparison, experimental and calculated electronic circular dichroism (ECD), and Mo2(OAc)4 induced circular dichroism (ICD) methods. The cytotoxicity of the isolates against selected human tumor cell lines was evaluated, however, the tested compounds showed no activity against selected cell lines.

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9

Toshima, Kazunobu, Takaaki Jyojima, Hiroyuki Yamaguchi, Hidekazu Murase, Taketo Yoshida, Shuichi Matsumura, and Masaya Nakata. "Total synthesis of bafilomycin A1. 1. Syntheses of the C5∼C11, C12∼C17 and C18∼C25 segments." Tetrahedron Letters 37, no. 7 (February 1996): 1069–72. http://dx.doi.org/10.1016/0040-4039(95)02350-x.

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10

Čejka, Jan, Jan Ondráček, Michal Hušák, Bohumil Kratochvíl, Alexandr Jegorov, and Josef Stuchlík. "Absolute Crystal Structure Determination of Ergot Alkaloid - Dihydroergocristine Methanesulfonate Monohydrate." Collection of Czechoslovak Chemical Communications 60, no. 8 (1995): 1333–42. http://dx.doi.org/10.1135/cccc19951333.

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Dihydroergocristine methanesulfonate monohydrate crystallizes in orthorhorhombic space group P21212 (No. 18) with Z = 4, a = 12.736(2) Å, b = 39.089(5) Å, c = 7.130(1) Å, V = 3549.6(9) Å3. The indole moiety is nearly planar, both the ergoline ring C and the tripeptide ring F addopt an envelope E6 conformation. The ergoline ring D and the tripeptide ring E have a chair 1C4 conformation. The conformation of the ring G is between E1 and 5T1. The benzene ring H is planar. The structure was solved by direct methods and refined anisotropically to the final R value of 0.078 for 4219 statistically significant observed reflections [I o 1.96s(I)]. The absolute chirality was determined based on anomalous dispersion as: C4 (R), C8 (R), C6 (R), C17 (R), C25 (S), C24 (S), C19 (S).

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11

Tibbetts, P. J. C. "Hydrocarbons in Nigg Bay sediments." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 91 (1986): 329–39. http://dx.doi.org/10.1017/s0269727000009404.

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SynopsisAs part of the Moray Firth environmental monitoring programme Britoil has commissioned a series of studies on the mudflats in Nigg Bay commencing in 1981. These cover an area of about five square miles and are situated in the Cromarty Firth adjacent to the oil terminal that handles crude oil from the Beatrice Field.Capillary gas liquid chromatography (GLC) analysis of the mudflat sediments in 1981 and 1982 showed a major autochthonous input of algal hydrocarbons as indicated by high n-C17 and C17 alkene concentrations. In addition there were low levels of petrogenic contamination, with concentrations of unresolved complex mixture (UCM), in general, being less than 10 ppm. These concentrations altered little between the two surveys during which time effluent discharge commenced from the oil terminal.In many of the GLC traces the dominant feature was an homologous series of n-alkanes in a smooth envelope from n-C22 to n-C34 with a maximum concentration at c. n-C25. This unusual distribution of n-alkanes does not appear to be associated with the UCM seen in many samples and may therefore not be of petrogenic origin. Possible sources of these components include bacteria and the erosion of local organic-rich shales, a selection of which have been sampled and analysed. Gas chromatography–mass spectrometry (GLC/MS) has been used in attempt to further clarify the origin of these n-alkanes.

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12

Martín, José, Jesús Ortega, and Pilar López. "Chemical Compounds from the Preanal Gland Secretions of the Male Tree Agama (Acanthocercus atricollis) (Fam. Agamidae)." Zeitschrift für Naturforschung C 68, no. 5-6 (June 1, 2013): 253–58. http://dx.doi.org/10.1515/znc-2013-5-612.

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Chemical signals have an important role in the reproductive behaviour of many lizards. However, the compounds secreted by their femoral or preanal glands, which may be used as sexual signals, are mainly known for lizard species within the Scleroglossa clade, whereas compounds in secretions of lizards within the Iguania clade are much less studied. Based on mass spectra, obtained by GC-MS, we found 60 lipophilic compounds in preanal gland secretions of the male tree agama (Acanthocercus atricollis) (fam. Agamidae), including steroids (mainly cholesterol, cholest-3-ene, and some of their derivatives), fatty acids ranging between n-C12 and n-C18 (mainly hexadecanoic and octadecenoic acids), ketones from n-C17 to n-C25, and other minor compounds, such as tocopherol, squalene, waxy esters, and furanones. We compare the compounds found with those present in other lizard species and discuss their potential function in social behaviour

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13

Tejeda, J. F., T. Antequera, J. Ruiz, R. Cava, J. Ventanas, and C. García. "Unsaponifiable fraction and n-alkane profile of subcutaneous fat from Iberian ham / Fracción insaponificable y perfil de los n-alcanos de la grasa subcutánea del jamón Ibérico." Food Science and Technology International 5, no. 3 (June 1999): 229–33. http://dx.doi.org/10.1177/108201329900500305.

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The unsaponifiable fraction of subcutaneous fat of dry-cured Iberian hams from pigs fed on different systems during the finishing-fattening period and its feasibility as a method for classifying the hams according to the pigs' feeding background are studied. Unsaponifiable fraction and n-alkane content of subcutaneous fat from ten dry cured hams from Iberian x Duroc pigs raised on two different man agement systems ( Montanera, fed extensively on acorns and pasture, and Pienso, fed on a concentrate diet) are analyzed. The proportion of unsaponifiable material and n-alkanes [pentadecane (n-C15), heptadecane (n-C17), octadecane (n-C18), nonadecane (n-C19), eicosane (n-C20) and pentacosane (n-C25)] were higher ( P < 0.05) in hams from pigs raised under extensive conditions than in those from pigs receiving concentrate feeds. The unsaponifiable fraction assay of the fat from dry-cured Iberian hams is a promising technique for classifying hams based on the pigs' feeding background.

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14

Makino, Kazuishi, Ken-ichi Kimura, Noriyuki Nakajima, Shun-ichi Hashimoto, and Osamu Yonemitsu. "Toward the total synthesis of hygrolidin: Stereocontrolled construction of the C1–C17 seco-acid fragment and the C18–C25 masked hemiacetal subunit." Tetrahedron Letters 37, no. 50 (December 1996): 9073–76. http://dx.doi.org/10.1016/s0040-4039(96)02132-6.

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15

TOSHIMA, K., T. JYOJIMA, H. YAMAGUCHI, H. MURASE, T. YOSHIDA, S. MATSUMURA, and M. NAKATA. "ChemInform Abstract: Total Synthesis of Bafilomycin A1. Part 1. Syntheses of the C5≅ C11 (I), C12≅C17 (II), and C18≅C25 (III) Segments." ChemInform 27, no. 22 (August 5, 2010): no. http://dx.doi.org/10.1002/chin.199622228.

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16

Abbade, Eduardo Botti. "Adoção de terapias nutricionais enteral e parenteral associada à redução da taxa de óbitos de pacientes neoplásicos." Medicina (Ribeirao Preto Online) 53, no. 2 (August 7, 2020): 115–25. http://dx.doi.org/10.11606/issn.2176-7262.v53i2p115-125.

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Modelo do estudo: Estudo descritivo transversal. Objetivo: Este estudo analisou a relação entre a adoção da nutrição enteral e parenteral adulta e o tempo de permanência médio, a taxa de óbitos e o custo das internações de pacientes neoplásicos em hospitais do Rio Grande do Sul. Método: Foram analisados os dados dissemináveis disponíveis no SIH/SUS de 2017 do Rio Grande do Sul específicos para internações realizadas sob o diagnóstico principal associado ao CID Cap. II (Neoplasmas). Os dados foram analisados por observação da média e teste de Kruskal Wallis. Resultados: Foi observada taxa de óbito significativamente inferior em pacientes neoplásicos que foram internados em UTI e que foram submetidos às terapias dietéticas enterais e/ou parenterais, em relação aos pacientes que não receberam tais suplementos, em casos de diagnóstico de neoplasias malignas no esôfago (C15), no intestino delgado (C17) e no pâncreas (C25). Já o tempo médio de permanência e valor total médio de internações de pacientes neoplásicos tendem a ser maior em pacientes que recebem terapias dietéticas enterais e/ou parenterais, possivelmente devido à gravidade do quadro clínico. Conclusão: A adoção de nutrição enteral e parenteral apresenta potencial significativo na redução da taxa de mortalidade de pacientes com câncer no sistema digestivo, principalmente dos casos mais graves que necessitam de internação em UTI.

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17

Li, Zhong-Xuan, and Hai-Ping Huang. "Bulk and molecular composition variations of gold-tube pyrolysates from severely biodegraded Athabasca bitumen." Petroleum Science 17, no. 6 (September 12, 2020): 1527–39. http://dx.doi.org/10.1007/s12182-020-00484-4.

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AbstractGold-tube pyrolysis experiments were performed on two Athabasca oil sand bitumens at 300 °C to 525 °C with 2 °C/h rate and 25 °C step under 50 MPa. Pyrolysis temperature of 425 °C is critical for weight loss of bulk bitumen and hydrocarbon generation and destruction. Polar compounds are the main source of saturated and aromatic hydrocarbon, gas and coke fractions. Molecular compositions in pyrolyzates vary systematically with increasing pyrolysis temperatures. High molecular weight n-alkanes (C26+) are gradually destructed during pyrolysis due to thermal cracking. Moderate molecular weight n-alkanes (C21–C25) show the highest thermal stability in designed pyrolysis temperatures. The loss of low molecular weight n-alkanes (C20−) might be caused by volatilization during pyrolysis, which may alter commonly used molecular parameters such as ∑n-C20−/∑n-C21+, Pr/n-C17 and Ph/n-C18. Aromatic hydrocarbons were generated from 300 to 425 °C, then condensation and dealkylation have been initiated at 425 °C as evidenced by decreased summed alkylnaphthalenes to alkylphenanthrenes ratios and increased unsubstituted aromatics to substituted homologs ratios in higher temperatures. The occurrence of anthracene and benz[a]anthracene in pyrolysates indicates pyrogenic origin, while fluoranthene shows unexpected behaviors during pyrolysis. Ratios derived from them are not always reliable for pyrogenic source input diagnosis in environmental samples.

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18

MAKINO, K., K. KIMURA, N. NAKAJIMA, S. HASHIMOTO, and O. YONEMITSU. "ChemInform Abstract: Toward the Total Synthesis of Hygrolidin: Stereocontrolled Construction of the C1-C17 Seco-Acid Fragment (I) and the C18-C25 (II) Masked Hemiacetal Subunit." ChemInform 28, no. 14 (August 4, 2010): no. http://dx.doi.org/10.1002/chin.199714210.

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19

Gola, Marek R., Michał Karger, Lucjan Gazda, and Oliwia Grafka. "Organic geochemistry of Upper Carboniferous bituminous coals and clastic sediments from the Lublin Coal Basin." Acta Geologica Polonica 63, no. 3 (September 1, 2013): 456–73. http://dx.doi.org/10.2478/agp-2013-0018.

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Abstract Bituminous coals and clastic rocks from the Lublin Formation (Pennsylvanian, Westphalian B) were subjected to detailed biomarker and Rock-Eval analyses. The investigation of aliphatic and aromatic fractions and Rock-Eval Tmax suggests that the Carboniferous deposits attained relatively low levels of thermal maturity, at the end of the microbial processes/initial phase of the oil window. Somewhat higher values of maturity in the clastic sediments were caused by postdiagenetic biodegradation of organic matter. The dominance of the odd carbon-numbered n-alkanes in the range n-C25 to n-C31 , high concentrations of moretanes and a predominance of C 28 and C29 steranes are indicative of a terrigenous origin of the organic matter in the study material. This is supported by the presence of eudesmane, bisabolane, dihydro-ar-curcumene and cadalene, found mainly in the coal samples. In addition, tri- and tetracyclic diterpanes, e. g. 16β(H)-kaurane, 16β(H)-phyllocladane, 16α(H)-kaurane and norisopimarane, were identified, suggesting an admixture of conifer ancestors among the deposited higher plants. Parameters Pr/n-C17 and Rdit in the coal samples show deposition of organic matter from peat swamp environments, with the water levels varying from high (water-logged swamp) to very low (ephemeral swamp). Clastic deposits were accumulated in a flood plain environment with local small ponds/lakes. In pond/lake sediments, apart from the dominant terrigenous organic matter, research also revealed a certain quantity of algal matter, indicated, i.a., by the presence of tricyclic triterpanes C28 and C29 and elevated concentrations of steranes. The Paq parameter can prove to be a useful tool in the identification of organic matter, but the processes of organic matter biodegradation observed in clastic rocks most likely influence the value of the parameter, at the same time lowering the interpretation potential of these compounds. The value of Pr/Ph varies from 0.93 to 5.24 and from 3.49 to 22.57 in the clastic sediments and coals respectively. The microbial degradation of organic matter in both type of rocks and during early stages of diagenesis is confirmed by a high concentration of hopanes, the presence of drimane homologues, bicyclic alkanes and benzohopanes. Moreover, bacteria could also have been connected with the primary input of organic matter, which is shown by the presence of e.g. C30 neohop-13(18)-ene.

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20

ZELLE, R. E., M. P. DENINNO, H. G. SELNICK, and S. J. DANISHEFSKY. "ChemInform Abstract: A Systematic Degradation of Zincophorin (I): Stereoselective Synthesis of the C17-C25 Fragment." ChemInform 18, no. 30 (July 28, 1987). http://dx.doi.org/10.1002/chin.198730315.

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21

Sarraj, Razawa Hamarashid A., and Ibrahim Mohammed J. Mohialdeen. "Organic Geochemistry and Thermal Maturity Assessment of Cretaceous Balambo Formation from Selected Sites, Kurdistan, NE Iraq." Iraqi Journal of Science, February 27, 2021, 532–54. http://dx.doi.org/10.24996/ijs.2021.62.2.20.

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The Cretaceous Balambo Formation from three sections in Kurdistan Region of Northern Iraq was studied. The selected sections are located in the Zagros Fold -Thrust Belt. Eleven rock samples were analyzed by means of the organic geochemical method, Bitumen extraction method, and gas chromatography/mass spectrometry to determine the bitumen and hydrocarbon content, kerogen types, origin of organic matter, thermal maturity level, and depositional environment. The analyzed samples are considered to have an excellent potential in Baranan-1.G1 and Sazan sections, with poor to fair potential in Baraw section. The Baranan-1.G1 source rocks are of type II kerogen (oil prone), whereas Sazan and Baraw samples are of type II/III (oil/ gas prone). Detailed distribution analysis of biomarkers such as normal alkane, isoprenoids, sterane and terpane was performed on saturated hydrocarbons. The mode of n-alkanes and isoprenoids distribution in all analyzed samples is similar, with a unimodal distribution that indicates non-biodegraded hydrocarbons, with the same range of alkane compounds between C13-C34 alkanes. The results of n-C17, pristane, n-C18 and phytane, and regular steranes show that the source rocks of Balambo Formation in Baranan-1.G1 are mainly rich with algal marine organic matter deposited under a reducing environment, while Baraw and Sazan sections are composed of mixed marine organic matter that refers to terrestrial land plants input deposited under reducing anoxic/dysoxic environments. Thermal maturation appraisal is deduced from Pristane/n-C17 versus Phytane/n-C18 diagram, Carbon Preference Index (CPI), C29 Î²Î²/ (Î²Î²+Î±Î±), C29 20S/ (20S +20R), C32 22S/ (22S+22R), and Ts/ (Ts+Tm). All these parameters indicate that the analyzed samples are mature and have entered the oil window (early to peak oil window). Biomarker ratios of C22/C21, C24/C23 and C26/C25, C31R/C30H show that the Balambo Formation is composed mostly of carbonates with less shale beds.

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