Use of a vinyl phosphonate analog of ATP as a rotationally constrained probe of the C5′O5′ torsion angle in ATP complexed to methionine adenosyl transferase

The synthesis and spectroscopic characterization of the glutaric acid-amide derivative, 2,4-Cl2C6H3N(H)C(=O)(CH2)3C(=O)OH (1), are described. The X-ray crystal structure determination of (1) shows the backbone of the molecule to be kinked about the methylene-C–N(amide) bond as seen in the C(p)–N–C(m)–C(m) torsion angle of −157.0(2)°; m = methylene and p = phenyl. An additional twist in the molecule is noted between the amide and phenyl groups as reflected in the C(m)–N–C(p)–C(p) torsion angle of 138.2(2)°. The most prominent feature of the molecular packing is the formation of supramolecular tapes assembled through carboxylic acid-O–H…O(carbonyl) and amide-N–H…O(amide) hydrogen bonding.

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Investigation of Mixing Behavior of Hydrogen Blended to Natural Gas in Gas Network

Sustainability ◽

10.3390/su13084255 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4255

Author(s):

Mingmin Kong ◽

Shuaiming Feng ◽

Qi Xia ◽

Chen Chen ◽

Zhouxin Pan ◽

...

Keyword(s):

Natural Gas ◽

Torsion Angle ◽

Carbon Dioxide Emissions ◽

Pressure Loss ◽

Optimum Number ◽

Hydrogen Energy ◽

Gas Mixing ◽

Gas Network ◽

Mixing Performance ◽

Mixing Behavior

Hydrogen is of great significance for replacing fossil fuels and reducing carbon dioxide emissions. The application of hydrogen mixing with natural gas in gas network transportation not only improves the utilization rate of hydrogen energy, but also reduces the cost of large-scale updating household or commercial appliance. This paper investigates the necessity of a gas mixing device for adding hydrogen to existing natural gas pipelines in the industrial gas network. A three-dimensional helical static mixer model is developed to simulate the mixing behavior of the gas mixture. In addition, the model is validated with experimental results. Parametric studies are performed to investigate the effect of mixer on the mixing performance including the coefficient of variation (COV) and pressure loss. The research results show that, based on the, the optimum number of mixing units is three. The arrangement of the torsion angle of the mixing unit has a greater impact on the COV. When the torsion angle θ = 120°, the COV has a minimum value of 0.66%, and when the torsion angle θ = 60°, the COV has a maximum value of 8.54%. The distance of the mixing unit has little effect on the pressure loss of the mixed gas but has a greater impact on the COV. Consecutive arrangement of the mixing units (Case A) is the best solution. Increasing the distance of the mixing unit is not effective for the gas mixing effect. Last but not least, the gas mixer is optimized to improve the mixing performance.

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Purine 8-bromination modulates the ribonuclease L binding and activation abilities of 2',5'-oligoadenylates. Possible influence of glycosyl torsion angle.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)61604-7 ◽

1987 ◽

Vol 262 (5) ◽

pp. 1961-1965

Author(s):

K. Lesiak ◽

P.F. Torrence

Keyword(s):

Torsion Angle ◽

Ribonuclease L

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Crystal structure of (3E)-3-(2,4-dinitrophenoxymethyl)-4-phenylbut-3-en-2-one

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536814018819 ◽

2014 ◽

Vol 70 (9) ◽

pp. o1051-o1052 ◽

Cited By ~ 2

Author(s):

Ignez Caracelli ◽

Stella H. Maganhi ◽

Paulo J. S. Moran ◽

Bruno R. S. de Paula ◽

Felix N. Delling ◽

...

Keyword(s):

Crystal Structure ◽

Double Bond ◽

Nitro Group ◽

Benzene Ring ◽

Torsion Angle ◽

Title Compound ◽

Phenyl Ring ◽

Aromatic Rings ◽

Compound C ◽

The One

In the title compound, C17H14N2O6, the conformation about the C=C double bond [1.345 (2) Å] isE, with the ketone moiety almost coplanar [C—C—C—C torsion angle = 9.5 (2)°] along with the phenyl ring [C—C—C—C = 5.9 (2)°]. The aromatic rings are almost perpendicular to each other [dihedral angle = 86.66 (7)°]. The 4-nitro moiety is approximately coplanar with the benzene ring to which it is attached [O—N—C—C = 4.2 (2)°], whereas the one in theorthoposition is twisted [O—N—C—C = 138.28 (13)°]. The molecules associateviaC—H...O interactions, involving both O atoms from the 2-nitro group, to form a helical supramolecular chain along [010]. Nitro–nitro N...O interactions [2.8461 (19) Å] connect the chains into layers that stack along [001].

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Algorithm and Application of Springback Modification for Complex Bending Parts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.1031 ◽

2012 ◽

Vol 538-541 ◽

pp. 1031-1034

Author(s):

Er Ming He ◽

Hong Wei Zhang ◽

Zhi Bin Zhao

Keyword(s):

Torsion Angle ◽

Experimental Results ◽

Engineering Project ◽

Practical Engineering ◽

Open Api ◽

Low Efficiency

To solve the problems of complex bending parts forming, such as low efficiency and accuracy, and loss of modification experience data, the algorithm of three parameters segment springback modification (TPSSM) based on arc approximation is presented in this paper. Firstly, the centroid line is divided into several arc sections according to the requirement and each section is modified based on presumptive correcting factor of radius, torsion and torsion angle. Then based on UG re-development, the program and UI of TPSSM are developed with UG/Open API and MFC. Finally, experimental results show that this method can effectively realize springback modification of bending parts, which is worthy for practical engineering project.

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PRTAD: A database for protein residue torsion angle distributions

International Journal of Data Mining and Bioinformatics ◽

10.1504/ijdmb.2009.029207 ◽

2009 ◽

Vol 3 (4) ◽

pp. 469 ◽

Cited By ~ 3

Author(s):

Xiaoyong Sun ◽

Di Wu ◽

Robert Jernigan ◽

Zhijun Wu

Keyword(s):

Torsion Angle

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Molecular Origins of the Unique Conformational Properties of the Polysilanes: A Molecular Dynamics Study of Poly(Di-N-Hexylsilane)

MRS Proceedings ◽

10.1557/proc-278-55 ◽

1992 ◽

Vol 278 ◽

Author(s):

William J. Welsh ◽

Samuel H. Tersigni ◽

Wangkan Lin

Keyword(s):

Molecular Dynamics ◽

Torsion Angle ◽

Model Compound ◽

Energy Surface ◽

Conformational Dynamics ◽

Conformational Transitions ◽

Torsion Angles ◽

Global Energy Minimum ◽

Conformational Properties ◽

Backbone Torsion Angle

AbstractThe conformational dynamics of a model compound for poly(di-n-hexylsilane) (PDHS) has been explored using the new molecular dynamics program MM3-MD. MM3-MD trajectories at variable temperatures reveal two abrupt conformational transitions, one near -182°C and another near -175°C, associated with two energy barriers on the potential-energy surface. The first transition near -182°C allows shifts in the backbone torsion angle from that defined by the global energy minimum designated off-trans to that corresponding to a statistical collection of torsion angles within the range trans ±30°. The second transition near -175°C allows the backbone torsion angle to explore the remainder of its torsional space. The sidechain dynamics follows a similar pattern. We suggest that the abrupt transition calculated here at -182°C for “gas.phase” PDHS corresponds to that observed for PDHS at -28°C in solution and at 42°C in the solid state.

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Crystal structure of 2,4-dinitrophenyl 4-methylbenzenesulfonate: a new polymorph

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989015015650 ◽

2015 ◽

Vol 71 (9) ◽

pp. 1085-1088 ◽

Cited By ~ 1

Author(s):

Tyler A. Cooley ◽

Sean Riley ◽

Shannon M. Biros ◽

Richard J. Staples ◽

Felix N. Ngassa

Keyword(s):

Crystal Structure ◽

Nucleophilic Substitution ◽

Torsion Angle ◽

Title Compound ◽

Substitution Reaction ◽

Sulfonate Group ◽

Acta Cryst ◽

Crystal Stability ◽

Compound C ◽

Centroid Distance

The title compound, C13H10N2O7S, was synthesizedviaa nucleophilic substitution reaction between 2,4-dinitrophenol andp-toluenesulfonyl chloride. This crystal structure is a polymorph of CSD entry WUVYUH [Vembuet al.(2003).Acta Cryst, E59, o378–380]. The aromatic substituents on the sulfonate group are orientedgaucheto one another with a C—O—S—C torsion angle of −62.0 (3)°. The supramolecular features that contribute to the crystal stability are offset π–π [centroid–centroid distance = 3.729 (2) Å] and multiple C—H...O interactions.

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