View source for 4ctn


==Glucopyranosylidene-spiro-iminothiazolidinone, a New Bicyclic Ring System: Synthesis, Derivatization, and Evaluation as Glycogen Phosphorylase Inhibitors by Enzyme Kinetic and Crystallographic Methods==
<StructureSection load='4ctn' size='340' side='right'caption='[[4ctn]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4ctn]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4CTN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4CTN FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DMS:DIMETHYL+SULFOXIDE'>DMS</scene>, <scene name='pdbligand=DTT:2,3-DIHYDROXY-1,4-DITHIOBUTANE'>DTT</scene>, <scene name='pdbligand=M8P:N-[(2Z,5R,7R,8S,9S,10R)-8,9,10-TRIHYDROXY-7-(HYDROXYMETHYL)-4-OXO-6-OXA-1-THIA-3-AZASPIRO[4.5]DEC-2-YLIDENE]NAPHTHALENE-2-CARBOXAMIDE'>M8P</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4ctn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ctn OCA], [https://pdbe.org/4ctn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ctn RCSB], [https://www.ebi.ac.uk/pdbsum/4ctn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ctn ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PYGM_RABIT PYGM_RABIT] Phosphorylase is an important allosteric enzyme in carbohydrate metabolism. Enzymes from different sources differ in their regulatory mechanisms and in their natural substrates. However, all known phosphorylases share catalytic and structural properties.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The reaction of thiourea with O-perbenzoylated C-(1-bromo-1-deoxy-beta-d-glucopyranosyl)formamide gave the new anomeric spirocycle 1R-1,5-anhydro-d-glucitol-spiro-[1,5]-2-imino-1,3-thiazolidin-4-one. Acylation and sulfonylation with the corresponding acyl chlorides (RCOCl or RSO2Cl where R=tBu, Ph, 4-Me-C6H4, 1- and 2-naphthyl) produced the corresponding 2-acylimino- and 2-sulfonylimino-thiazolidinones, respectively. Alkylation by MeI, allyl-bromide and BnBr produced mixtures of the respective N-alkylimino- and N,N'-dialkyl-imino-thiazolidinones, while reactions with 1,2-dibromoethane and 1,3-dibromopropane furnished spirocyclic 5,6-dihydro-imidazo[2,1-b]thiazolidin-3-one and 6,7-dihydro-5H-thiazolidino[3,2-a]pyrimidin-3-one, respectively. Removal of the O-benzoyl protecting groups by the Zemplen protocol led to test compounds most of which proved micromolar inhibitors of rabbit muscle glycogen phosphorylase b (RMGPb). Best inhibitors were the 2-benzoylimino- (Ki=9muM) and the 2-naphthoylimino-thiazolidinones (Ki=10muM). Crystallographic studies of the unsubstituted spiro-thiazolidinone and the above most efficient inhibitors in complex with RMGPb confirmed the preference and inhibitory effect that aromatic (and especially 2-naphthyl) derivatives show for the catalytic site promoting the inactive conformation of the enzyme.

Glucopyranosylidene-spiro-iminothiazolidinone, a new bicyclic ring system: Synthesis, derivatization, and evaluation for inhibition of glycogen phosphorylase by enzyme kinetic and crystallographic methods.,Czifrak K, Pahi A, Deak S, Kiss-Szikszai A, Kover KE, Docsa T, Gergely P, Alexacou KM, Papakonstantinou M, Leonidas DD, Zographos SE, Chrysina ED, Somsak L Bioorg Med Chem. 2014 Aug 1;22(15):4028-41. doi: 10.1016/j.bmc.2014.05.076. Epub , 2014 Jun 16. PMID:25009003<ref>PMID:25009003</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4ctn" style="background-color:#fffaf0;"></div>

==See Also==
*[[Glycogen phosphorylase 3D structures|Glycogen phosphorylase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Oryctolagus cuniculus]]
[[Category: Alexacou KM]]
[[Category: Chrysina ED]]
[[Category: Leonidas DD]]
[[Category: Papakonstantinou M]]
[[Category: Zographos SE]]