A new class of focusing crystal shapes for Bragg spectroscopy of small, point-like, x-ray sources in laser produced plasmas

Glutaminase (GLS), which is responsible for the conversion of glutamine to glutamate, plays a vital role in up-regulating cell metabolism for tumor cell growth and is considered to be a valuable therapeutic target for cancer treatment. Based on this important function of glutaminase in cancer, several GLS inhibitors have been developed in both academia and industry. Most importantly, Calithera Biosciences Inc. is actively developing the glutaminase inhibitor CB-839 for the treatment of various cancers, and it is currently being evaluated in phase 1 and 2 clinical trials. In this review, recent efforts to develop small molecule glutaminase inhibitors that target glutamine metabolism in both preclinical and clinical studies are discussed. In particular, more emphasis is placed on CB-839 because it is the only small molecule GLS inhibitor being studied in a clinical setting. The inhibition mechanism is also discussed based on X-ray structure studies of thiadiazole derivatives present in glutaminase inhibitor BPTES. Finally, recent medicinal chemistry efforts to develop a new class of GLS inhibitors are described in the hopes of providing useful information for the next generation of GLS inhibitors.

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Tuning π-Acceptor/σ-Donor Ratio of the 2-Isocyanoazulene Ligand: Non-Fluorinated Rival of Pentafluorophenyl Isocyanide and Trifluorovinyl Isocyanide Discovered

Molecules ◽

10.3390/molecules26040981 ◽

2021 ◽

Vol 26 (4) ◽

pp. 981

Author(s):

Mason D. Hart ◽

John J. Meyers ◽

Zachary A. Wood ◽

Toshinori Nakakita ◽

Jason C. Applegate ◽

...

Keyword(s):

Charge Transfer ◽

Coordination Chemistry ◽

Single Crystal ◽

13C Nmr ◽

Quantitative Assessment ◽

X Ray ◽

New Class ◽

Linear Relationships ◽

Ligand Charge Transfer ◽

Donor Characteristics

Isocyanoazulenes (CNAz) constitute a relatively new class of isocyanoarenes that offers rich structural and electronic diversification of the organic isocyanide ligand platform. This article considers a series of 2-isocyano-1,3-X2-azulene ligands (X = H, Me, CO2Et, Br, and CN) and the corresponding zero-valent complexes thereof, [(OC)5Cr(2-isocyano-1,3-X2-azulene)]. Air- and thermally stable, X-ray structurally characterized 2-isocyano-1,3-dimethylazulene may be viewed as a non-benzenoid aromatic congener of 2,6-dimethyphenyl isocyanide (2,6-xylyl isocyanide), a longtime “workhorse” aryl isocyanide ligand in coordination chemistry. Single crystal X-ray crystallographic {Cr–CNAz bond distances}, cyclic voltametric {E1/2(Cr0/1+)}, 13C NMR {δ(13CN), δ(13CO)}, UV-vis {dπ(Cr) → pπ*(CNAz) Metal-to-Ligand Charge Transfer}, and FTIR {νN≡C, νC≡O, kC≡O} analyses of the [(OC)5Cr(2-isocyano-1,3-X2-azulene)] complexes provided a multifaceted, quantitative assessment of the π-acceptor/σ-donor characteristics of the above five 2-isocyanoazulenes. In particular, the following inverse linear relationships were documented: δ(13COtrans) vs. δ(13CN), δ(13COcis) vs. δ(13CN), and δ(13COtrans) vs. kC≡O,trans force constant. Remarkably, the net electron withdrawing capability of the 2-isocyano-1,3-dicyanoazulene ligand rivals those of perfluorinated isocyanides CNC6F5 and CNC2F3.

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A new class of hydride-bridged platinum complex with application as hydrosilylation catalysts; molecular and X-ray crystal structure of trans-di-µ-hydrido-bis(tricyclohexylphosphine)bis(triethylsilyl)diplatinum(Pt–Pt)

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39760000671 ◽

1976 ◽

pp. 671-672 ◽

Cited By ~ 33

Author(s):

Michael Green ◽

Judith A. K. Howard ◽

Jill Proud ◽

John L. Spencer ◽

F. Gordon A. Stone ◽

...

Keyword(s):

Crystal Structure ◽

Platinum Complex ◽

X Ray ◽

New Class

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Acnistins, a new class of steroidal lactones from Acnistus ramiflorum Miers; X-ray structure of acnistin E

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39800000854 ◽

1980 ◽

pp. 854 ◽

Cited By ~ 8

Author(s):

Alfredo Usubillaga ◽

G. de Castellano ◽

V. Zabel ◽

William H. Watson

Keyword(s):

X Ray ◽

New Class

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Binary Amplitude Reflection Gratings for X-ray Shearing and Hartmann Wavefront Sensors

Sensors ◽

10.3390/s21020536 ◽

2021 ◽

Vol 21 (2) ◽

pp. 536

Author(s):

Kenneth A. Goldberg ◽

Antoine Wojdyla ◽

Diane Bryant

Keyword(s):

Operating Conditions ◽

Design Parameters ◽

Wavefront Aberration ◽

Light Sources ◽

Wavefront Sensors ◽

X Ray ◽

New Class ◽

Coherent Wave ◽

Reflection Gratings ◽

Dynamic Operating

New, high-coherent-flux X-ray beamlines at synchrotron and free-electron laser light sources rely on wavefront sensors to achieve and maintain optimal alignment under dynamic operating conditions. This includes feedback to adaptive X-ray optics. We describe the design and modeling of a new class of binary-amplitude reflective gratings for shearing interferometry and Hartmann wavefront sensing. Compact arrays of deeply etched gratings illuminated at glancing incidence can withstand higher power densities than transmission membranes and can be designed to operate across a broad range of photon energies with a fixed grating-to-detector distance. Coherent wave-propagation is used to study the energy bandwidth of individual elements in an array and to set the design parameters. We observe that shearing operates well over a ±10% bandwidth, while Hartmann can be extended to ±30% or more, in our configuration. We apply this methodology to the design of a wavefront sensor for a soft X-ray beamline operating from 230 eV to 1400 eV and model shearing and Hartmann tests in the presence of varying wavefront aberration types and magnitudes.

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Removeal of Arsenic(III) from Water by Using a New Class of Zero-Valent Iron Modified Mesoporous Silica Molecular Sieves SBA-15

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.423 ◽

2011 ◽

Vol 356-360 ◽

pp. 423-429

Author(s):

Meng Ye ◽

Jin Huang ◽

Rui Chen ◽

Qi Zhuang He

Keyword(s):

Molecular Sieves ◽

Cost Effective ◽

Zero Valent Iron ◽

Preparation Process ◽

X Ray Diffraction ◽

Wet Impregnation ◽

X Ray ◽

New Class ◽

Transmission Electron ◽

Removal Of Arsenic

An elevated arsenic (As) content in groundwater imposes a great threat to people worldwide. Thus, developing new and cost-effective methods to remove As from groundwater and drinking water becomes a priority. Using Zero-Valent iron (ZVI) to remove As from water is a proven technology. In this study, ZVI modified SBA-15 mesoporous silicamolecular sieves (ZVI-SBA-15), was prepared, characterized, and used for removing arsenic from water. Wet impregnation, drying, and calcination steps led to iron inclusion within the mesopores. Iron oxide was reduced to ZVI by NaBH4, and the ZVI modified SBA-15 was obtained. Fourier-transform infrared spectroscopy conﬁrmed the preparation process of the nitrate to oxide forms. The structure of the materials was conﬁrmed by Powder X-ray diﬀraction. Its data indicated that the structure of ZVI-SBA-15 retained the host SBA-15 structure. Brunauer-Emmett-Teller analysis revealed a decrease in surface area and pore size, indicating ZVI-SBA-15 coating on the inner surfaces. Transmission electron micrographs also conﬁrmed that modiﬁed SBA-15 retained the structure of the parent SBA-15 silica.It has a high uptake capability(more than 90 pecent) make it potentially attractive absorbent for the removal of arsenic from water.

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Syntheses and Properties of k-Phase Organic Superconductors

MRS Proceedings ◽

10.1557/proc-247-471 ◽

1992 ◽

Vol 247 ◽

Cited By ~ 1

Author(s):

H. Hau Wang ◽

K. D. Carlson ◽

U. Geiser ◽

A. M. Kini ◽

A. J. Schultz ◽

...

Keyword(s):

Phase Transition ◽

Ambient Pressure ◽

Density Wave ◽

Spin Density Wave ◽

Organic Superconductors ◽

Organic Superconductor ◽

X Ray ◽

New Class ◽

Structural Differences ◽

Similarities And Differences

ABSTRACTThe syntheses and physical properties of K-(ET)2CU[N(CN)2]X (X = Br and Cl) are summarized. The K-(ET)2Cu [N(CN)2] Br salt is the highest Tc radical-cation based ambient pressure organic superconductor (Tc = 11.6 K), and the K-(ET)2CU [N(CN)2] C1 salt becomes a superconductor at even higher Tc under 0.3 kbar hydrostatic pressure (Tc = 12.8 K). The similarities and differences between K-(ET)2Cu[N(CN)2]Br and K-(ET)2CU(NCS)2 (TC = 10.4 K) are presented. The X-ray structures at 127 K reveal that the S-S contacts shorten between ET dimers in the former compound while the S-S contacts shorten within dimers in the latter. The differences in their ESR linewidth behavior is also explained in terms of the structural differences. A semiconducting compound, (ET)Cu[N(CN)2]2, isolated during K-(ET)2Cu[N(CN)2]Cl synthesis is also reported. The ESR measurements of the K-(ET)2Cu[N(CN)2]Cl salt indicate that the phase transition near 40 K is similar to the spin density wave transition in (TMTSF)2SbF6. A new class of organic superconductors, K-(ET)2CU2(CN)3 and K-(ET)2Cu2(CN)3.δBrδ, is reported with Tc's of 2.8 K (1.5 kbar) and 2.6 K (1 kbar), respectively.

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Preparation of Highly Conductive Polyaniline in Carbamide Aqueous Solution Using SnCl4 as Initiator

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.2205 ◽

2012 ◽

Vol 476-478 ◽

pp. 2205-2208 ◽

Cited By ~ 1

Author(s):

Guan Nan Lin ◽

Qun Yu ◽

Wei Wang ◽

Gui Bao Wang

Keyword(s):

Aqueous Solution ◽

Ammonium Persulfate ◽

Conductivity Measurements ◽

X Ray ◽

New Class ◽

Vis Spectroscopy ◽

Polymerization System ◽

Novel Method ◽

Conductive Polyaniline ◽

Hydrolysis Of

In this paper, we demonstrated a novel method for the preparation of highly conductive polyaniline (PANI) compounded with Sn(OH)4. We obtained the PANI directly in the oxidation polymerization system via simultaneous reaction of aniline (using ammonium persulfate, APS as oxidant) and SnCl4 in carbamide aqueous solution. The resulting PANI was compounded with Sn(OH)4 had been characterized by FTIR, UV-Vis spectroscopy, X-ray diffractometry, thermal analysis, scanning electron microscope and conductivity measurements, and the results showed that PANI was in well doped state due to the hydrolysis of APS and the complex between PANI and Sn(OH)4. We are sure this alkali-guided polymerization to obtain conductive PANI will lead to the preparation of a new class of PANI composites.

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