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Phase annealing in SHELX-90: direct methods for larger structures
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TLDR
In this article, a phase annealing method, related to the simulated-annealing approach in other optimization problems, is proposed and it is shown that it can result in an improvement of up to an order of magnitude in the chances of solving large structures at atomic resolution.Abstract:
A number of extensions to the multisolution approach to the crystallographic phase problem are discussed in which the negative quartet relations play an important role. A phase annealing method, related to the simulated annealing approach in other optimization problems, is proposed and it is shown that it can result in an improvement of up to an order of magnitude in the chances of solving large structures at atomic resolution. The ideas presented here are incorporated in the program system SHELX-90; the philosophical and mathematical background to the direct-methods part (SHELXS) of this system is described.read more
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Nimesulide Silver Metallodrugs, Containing the Mitochondriotropic, Triaryl Derivatives of Pnictogen; Anticancer Activity against Human Breast Cancer Cells
Christina N. Banti,Constantina Papatriantafyllopoulou,Maria Manoli,Anastasios J. Tasiopoulos,Sotiris K. Hadjikakou +4 more
TL;DR: The in vitro cytotoxic activity of 1-5 against human breast adenocarcinoma cancer cell lines: MCF-7 (estrogen receptor (ER) positive) and MDA-MB-231 (ER negative) was determined and the genotoxicity on normal human fetal lung fibroblast cells (MRC-5) caused by 1- 5 was evaluated by fluorescence microscopy.
Journal ArticleDOI
The structure of human 5'-deoxy-5'-methylthioadenosine phosphorylase at 1.7 A resolution provides insights into substrate binding and catalysis.
TL;DR: The overall quaternary structure and subunit topology of MTAP are similar to mammalian purine nucleoside phosphorylase (PNP).The structures of the MTAP-ligand complexes provide a map of the active site and suggest possible roles for specific residues in substrate binding and catalysis.
Journal ArticleDOI
Ten-membered lactones from Phomopsis sp., an endophytic fungus of Azadirachta indica.
Shao-Hua Wu,You-Wei Chen,Shi-Cheng Shao,Li-Dong Wang,Zhi-Ying Li,Li-Yuan Yang,Shao-Lan Li,Rong Huang +7 more
TL;DR: Four new 10-membered lactones and one known one were isolated from the broth extract of an endophytic fungus, Phomopsis sp.
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Syntheses, Characterization, and Structural Studies of Several (Nitro)(nitrosyl)iron(III) Porphyrinates: [Fe(Porph)(NO2)(NO)]
TL;DR: In this article, the preparation and characterization of several (nitro)(nitrosyl)iron(III) complexes, [Fe(Porph)(NO2)(NO)], where Porph = tetraphenylporphyrin, octaethyl porphyrIN, tetra-p-methoxyphenyl porphrin, or picket fence porphyrin are described.
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Supramolecular Design of Coordination Complexes of Silver(I) with Polyimine Ligands: Synthesis, Materials Characterization, and Structure of New Polymeric and Oligomeric Materials
Goutam K. Patra,Israel Goldberg +1 more
TL;DR: A series of new coordination polymers and oligomers of polyimine ligands with silver(I) ions have been synthesized and characterized by single-crystal X-ray diffraction studies, elemental analysis, IR, UV−Vis, and NMR spectroscopy as discussed by the authors.
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Book
Crystallographic Computing 3: Data Collection, Structure Determination, Proteins and Databases
TL;DR: The latest in a series on crystallographic computing, this collection of 33 papers covers the full spectrum of computer applications in crystallography, including the use of micro-, mini-, and mainframe computers.