- S-Carboxyanhydrides: Ultrafast and Selective Ring-Opening Polymerizations Towards Well-defined Functionalized Polythioesters
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Aliphatic polythioesters are popular polymers because of their appealing performance such as metal coordination ability, high refractive indices, and biodegradability. One of the most powerful approaches for generating these polymers is the ring-opening polymerization (ROP) of cyclic monomers. However, the synthesis of precisely controlled polythioesters via ROP of thiolactones still faces formidable challenges, including the minimal functional diversity of available thiolactone monomers, as well as inevitable transthioesterification side reactions. Here we introduce a hyperactive class of S-carboxyanhydride (SCA) monomers derived from amino acids that are significantly more reactive than thiolactones for ultrafast and selective ROP. Inclusion of the initiator PPNOBz ([PPN]=bis(triphenylphosphine)-iminium) with chain transfer agent benzoic acid, the polymerizations that can be operated in open vessels reach complete conversion within minutes (1–2 min) at room temperature, yielding polythioesters with predictable molecular weight, low dispersities, retained stereoregularity and chemical recyclability. Most fascinating are the functionalized SCAs that allow the incorporating of functional groups along the polythioester chain and thus finely tune their physicochemical performance. Computational studies were carried out to explore the origins of the distinctive rapidity and exquisite selectivity of the polymerizations, offering mechanistic insight and explaining why high polymerizability of SCA monomer is able to facilitate exquisitely selective ring-opening for enchainment over competing transthioesterification and backbiting reactions.
- Wang, Yanchao,Li, Maosheng,Wang, Shixue,Tao, Youhua,Wang, Xianhong
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supporting information
p. 10798 - 10805
(2021/03/31)
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- Ruthenium(II)–Arene Thiocarboxylates: Identification of a Stable Dimer Selectively Cytotoxic to Invasive Breast Cancer Cells
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RuII-arene complexes provide a versatile scaffold for novel anticancer drugs. Seven new RuII-arene-thiocarboxylato dimers were synthesized and characterized. Three of the complexes (2 a, b and 5) showed promising antiproliferative activities in MDA-MB-231 (human invasive breast cancer) cells, and were further tested in a panel of fifteen cancerous and noncancerous cell lines. Complex 5 showed moderate but remarkably selective activity in MDA-MB-231 cells (IC50=39±4 μm Ru). Real-time proliferation studies showed that 5 induced apoptosis in MDA-MB-231 cells but had no effect in A549 (human lung cancer, epithelial) cells. By contrast, 2 a and b showed moderate antiproliferative activity, but no apoptosis, in either cell line. Selective cytotoxicity of 5 in aggressive, mesenchymal-like MDA-MB-231 cells over many common epithelial cancer cell lines (including noninvasive breast cancer MCF-7) makes it an attractive lead compound for the development of specifically antimetastatic Ru complexes with low systemic toxicity.
- Stephens, Liam J.,Levina, Aviva,Trinh, Iman,Blair, Victoria L.,Werrett, Melissa V.,Lay, Peter A.,Andrews, Philip C.
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p. 1188 - 1200
(2019/12/24)
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- Direct synthesis of α-thio aromatic acids from aromatic amino acids
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Modified amino acids are useful synthetic components in both chemistry and biology. Here we describe a simple, scalable two-step procedure to generate α-thio aromatic acids from aromatic amino acids with yields of up to 96%. Diazotization and α-lactone me
- Samuels, Eric R.,Sevrioukova, Irina F.
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p. 1140 - 1142
(2018/02/23)
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- Structure activity relationship studies on rhodanines and derived enethiol inhibitors of metallo-β-lactamases
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Metallo-β-lactamases (MBLs) enable bacterial resistance to almost all classes of β-lactam antibiotics. We report studies on enethiol containing MBL inhibitors, which were prepared by rhodanine hydrolysis. The enethiols inhibit MBLs from different subclasses. Crystallographic analyses reveal that the enethiol sulphur displaces the di-Zn(II) ion bridging ‘hydrolytic’ water. In some, but not all, cases biophysical analyses provide evidence that rhodanine/enethiol inhibition involves formation of a ternary MBL enethiol rhodanine complex. The results demonstrate how low molecular weight active site Zn(II) chelating compounds can inhibit a range of clinically relevant MBLs and provide additional evidence for the potential of rhodanines to be hydrolysed to potent inhibitors of MBL protein fold and, maybe, other metallo-enzymes, perhaps contributing to the complex biological effects of rhodanines. The results imply that any medicinal chemistry studies employing rhodanines (and related scaffolds) as inhibitors should as a matter of course include testing of their hydrolysis products.
- Zhang, Dong,Markoulides, Marios S.,Stepanovs, Dmitrijs,Rydzik, Anna M.,El-Hussein, Ahmed,Bon, Corentin,Kamps, Jos J.A.G.,Umland, Klaus-Daniel,Collins, Patrick M.,Cahill, Samuel T.,Wang, David Y.,von Delft, Frank,Brem, Jürgen,McDonough, Michael A.,Schofield, Christopher J.
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supporting information
p. 2928 - 2936
(2018/04/19)
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- Catalytic enantioselective synthesis of tertiary thiols from 5h-thiazol-4-ones and nitroolefins: Bifunctional ureidopeptide-based bronsted base catalysis
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Fully loaded: The ureidopeptide-based bifunctional Bronsted base 1 efficiently promotes the first direct catalytic Michael reaction of α-mercapto carboxylate surrogates with nitroolefins involving a fully substituted α-carbon atom construction. Copyright
- Diosdado, Saioa,Etxabe, Julen,Izquierdo, Joseba,Landa, Aitor,Mielgo, Antonia,Olaizola, Iurre,Lopez, Rosa,Palomo, Claudio
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supporting information
p. 11846 - 11851
(2013/11/19)
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- Synthesis and reaction of 2-mercapto-3-arylpropanoic acids
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Two synthetic pathways for the preparation of 2-mercapto-3-arylpropanoic acids were developed. First, by the reaction of arenediazonium bromides with acrylic esters in the presence of CuBr, alkyl (2-bromo-3-aryl)propanoates were formed. Their cyclization with thiourea produced 5-(R-benzyl)-2-imino-4- thiazolidinones, which yielded 3-aryl-2-mercaptopropanoic acids by alkaline hydrolysis. Second, direct Meerwein arylation of acrylates in the presence of S-nucleophile (NaSH) allowed isolation of 3-phenyl-2-mercaptopropanoic acid in 8% yield. Such acids were used for cyclization with cyanoguanidine and phenyl isothiocyanate yielding 1-[5-(R-benzyl)-4-oxo-1,3-thiazolidin-2-ylidene] guanidines and new 5-(R-benzyl)-3-phenyl-2-thioxo-1,3-thiazolidin-4-one (rhodanine) derivatives correspondingly. Copyright Taylor and Francis Group, LLC 2012.
- Pokhodylo, Nazariy T.,Matiychuk, Vasyl S.,Obushak, Mykola D.
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experimental part
p. 850 - 858
(2012/08/07)
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- DERIVATIVES OF SUCCINIC AND GLUTARIC ACIDS AND ANALOGS THEREOF USEFUL AS INHIBITORS OF PHEX
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The present invention relates to derivatives of succinic and glutaric acids and analogues thereof, having the following general formula (I), useful as inhibitors of PHEX. These derivatives are useful for promoting generation of bone mass and treating or preventing diseases or conditions associated with a phosphate metabolism defect. Methods for preparation and intermediates are also disclosed.
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- Design and synthesis of chromogenic thiopeptolide substrates as MetAPs active site probes
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Twenty one chromogenic thiopeptolide substrates were designed and synthesized as the active site probes and analyzed with each S1 site of mutant residues and enzymes of wild-type MetAP1s. The preliminary enzymatic experiments indicate that cysteine 70 or 202, at either Escherichia coli or human MetAP1, played a crucial role in the methionine hydrolysis.
- Cui, Yong-Mei,Li, Jing-Ya,Chen, Ling-Ling,Li, Jia,Ye, Qi-Zhuang,Nan, Fa-Jun
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p. 2853 - 2861
(2007/10/03)
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- Synthesis and SAR of thioester and thiol inhibitors of IMP-1 metallo-β-lactamase
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Potent thioester and thiol inhibitors of IMP-1 metallo-β-lactamase have been synthesized employing a solid-phase Mitsunobu reaction as the key step.
- Greenlee, Mark L.,Laub, Joanne B.,Balkovec, James M.,Hammond, Milton L.,Hammond, Gail G.,Pompliano, David L.,Epstein-Toney, Jeffrey H.
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p. 2549 - 2554
(2007/10/03)
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- Inhibition of carboxypeptidase A by (S)-2-mercapto-3-phenylpropanoic acid
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(S)-2-Mercapto-3-phenylpropanoic acid is an effective competitive inhibitor of carboxypeptidase A, comparable in potency to (S)-3-mercapto-2-benzylpropanoic acid.
- Lanthier, Christopher M.,MacKinnon, Gregory R.,Dmitrienko, Gary I.
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p. 2309 - 2310
(2007/10/03)
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- Peptidylaminodiols
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A renin inhibiting compound of the formula: STR1 wherein A is a substituent; W is C=O or CHOH; U is CH2 or NR2, provided that when W is CHOH then U is CH2 ; R1 is loweralkyl, cycloalkylmethyl, benzyl, 4-methoxybenzyl, halobenzyl, (1-naphthyl)methyl, (2-naphthyl)methyl, (4-imidazoyl)methyl, (alpha,alpha)-dimethylbenzyl, 1-benzyloxyethyl, phenethyl, phenoxy, thiophenoxy or anilino; R2 is hydrogen or loweralkyl; R3 is loweralkenyl, [(alkoxy)alkoxy]alkyl, (thioalkoxy)alkyl, lowerakenyl, benzyl or heterocyclic ring substituted methyl; R4 is loweralkyl, cycloalkylmethyl or benzyl; R5 is vinyl, formyl, hydroxymethyl or hydrogen; R7 is hydrogen or loweralkyl; R8 and R9 are independently selected from OH and NH2 ; and R6 is hydrogen, loweralkyl, vinyl or arylalkyl; provided that when R5 and R7 are both hydrogen and R8 and R9 are OH, the carbon bearing R5 is of the "R" configuration and the carbon bearing R6 is of the "S" configuration, or pharmaceutically acceptable salts or esters thereof. Also disclosed are renin inhibiting compositions, a method of treating hypertension, methods of making the renin inhibiting compounds and intermediates useful in making the renin inhibiting compounds.
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- Organotin-containing composition for the stabilization of polymers of vinyl chloride
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An organotin-containing composition for the stabilization of polymers or copolymers of vinyl chloride in which there is incorporated a stabilizing amount of an organotin compound containing at least two tin atoms and which is a mercapto, hydroxy or alkoxy substituted ester of a mercapto acid substituted organotin mercapto acid diester.
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