- New 4-aryl-1,3,2-oxathiazolylium-5-olates: Chemical synthesis and photochemical stability of a novel series of S-nitrosothiols
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S-nitrosothiols (RSNOs) remain one of the most popular classes of NO-donating compounds due to their ability to release nitric oxide (NO) under non-enzymatic means whilst producing an inert disulphide by-product. However, alligning these compounds to the different biological fields of NO research has proved to be problematic due to the inherent instability of such compounds under a variety of conditions including heat, light and the presence of copper ions. 1,3,2-Oxathiazolylium-5-olates (OZOs) represent an interesting subclass of S-nitrosothiols that lock the –SNO moiety into a five membered heterocyclic ring in an attempt to improve the compound's overall stability. The synthesis of a novel series of halogen-containing OZOs was comprehensively studied resulting in a seven-step route and overall yields ranging between 21 and 37%. The photochemical stability of these compounds was assessed to determine if S-nitrosothiols locked within these mesoionic ring systems can offer greater stability and thereby release NO in a more controllable fashion than their non-cyclic counterparts.
- Eilertsen, Monica,Allin, Steve M.,Pearson, Russell J.
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p. 1106 - 1110
(2018/02/28)
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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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p. 2928 - 2936
(2018/04/19)
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- Reactions of α-mercaptocarboxylic acid hydrazides with triethyl orthoesters: Synthesis of 1,3,4-thiadiazin-5(6H)-ones and 1,3,4-oxadiazoles
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Reactions of α-mercapto-β-phenylpropionic and α-mercaptophenylacetic acid hydrazides with triethyl orthoesters were conducted under N2 in glacial acetic acid and resulted in the formation of two groups of products, derivatives of 1,3,4-thiadiazin-5(6H)-ones and 2-(1-mercaptomethyl)-1,3,4-oxadiazoles. When conducting the same transformations on α-mercaptophenylacetic acid hydrazide in the presence of air, two different products from the 1,3,4-oxadiazole family, the appropriate bis(1,3,4-oxadiazol-2-yl-phenylmethyl) disulfides and 2-benzyl-1,3,4- oxadiazoles, were formed with the liberation of free sulfur. The oxygenated bis(1,3,4-oxadiazol-2-yl-phenylmethyl) disulfides were reduced to the corresponding 2-(1-mercaptomethyl)-1,3,4-oxadiazoles with the use of zinc powder under mild conditions.
- Kudelko, Agnieszka
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experimental part
p. 3616 - 3625
(2012/06/18)
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- AMIDO-ISOTHIAZOLE COMPOUNDS AND THEIR USE AS INHIBITORS OF 11BETA-HSD1 FOR THE TREATMENT OF METABOLIC SYNDROME AND RELATED DISORDERS
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The present invention pertains generally to the field of therapeutic compounds. More specifically the present invention pertains to certain amido-isothiazole compounds that, inter alia, inhibit 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). The present invention also pertains to pharmaceutical compositions comprising such compounds, and the use of such compounds and compositions, both in vitro and in vivo, to inhibit 11β-hydroxysteroid dehydrogenase type 1; to treat disorders that are ameliorated by the inhibition of 11β-hydroxysteroid dehydrogenase type 1; to treat the metabolic syndrome, which includes disorders such as type 2 diabetes and obesity, and associated disorders including insulin resistance, hypertension, lipid disorders and cardiovascular disorders such as ischaemic (coronary) heart disease; to treat CNS disorders such as mild cognitive impairment and early dementia, including Alzheimer's disease; etc.
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Page/Page column 77
(2010/12/31)
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- 4-Aryl-1,3,2-oxathiazolylium-5-olates as pH-controlled NO-donors: The next generation of S-nitrosothiols
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S-Nitrosothiols (RSNOs) are important exogenous and endogenous sources of nitric oxide (NO) in biological systems. A series of 4-aryl-1,3,2- oxathiazolylium-5-olates derivatives with varying aryl para-substituents (-CF3, -H, -Cl, and -OCH3) were synthesized. These compounds were found to release NO under acidic condition (pH = 5). The decomposition pathway of the aryloxathiazolyliumolates proceeded via an acid-catalyzed ring-opening mechanism after which NO was released and an S-centered radical was generated. Electron paramagnetic resonance (EPR) spin trapping studies were performed to detect NO and the S-centered radical using the spin traps of iron(II) N-methyl-D-glucamine dithiocarbamate [(MGD) 2-FeII] and 5,5-dimethyl-1-pyrroline N-oxide (DMPO). Also, EPR spin trapping and UV-vis spectrophotometry were used to analyze the effect of aryl para substitution on the NO-releasing property of aryloxathiazolyliumolates. The results showed that the presence of an electron-withdrawing substituent such as -CF3 enhanced the NO-releasing capability of the aryloxathiazolyliumolates, whereas an electron-donating substituent like methoxy (-OCH3) diminished it. Computational studies using density functional theory (DFT) at the PCM/B3LYP/6-31+G*7/B3LYP/6-31G* level were used to rationalize the experimental observations. The aryloxathiazolyliumolates diminished susceptibility to reduction by ascorbate or gluthathione, and their capacity to cause vasodilation as compared to other S-nitrosothiols suggests potential application in biological systems.
- Lu, Dongning,Nadas, Janos,Zhang, Guisheng,Johnson, Wesley,Zweier, Jay L.,Cardounel, Arturo J.,Villamena, Frederick A.,Wang, Peng George
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p. 5503 - 5514
(2008/02/07)
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- Oxathi(SIV)azol-5-one compounds
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The present invention relates to the compounds of formula (I). STR1 wherein R1 is C1-8 alkyl, C2-8 alkenyl, C5-8 cycloalkyl, aryl-C1-4 alkyl, aryl or heteroaryl; or aryl or heteroaryl which is mono-,
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- SUBSTITUTED-4-THIAZOLIDINONE DERIVATIVES
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Disclosed are novel substituted 4-thiazolidinone derivatives having cyclooxygenase and 5-lipoxygenase inhibiting properties and which are topical antiinflammatory agents for inflammed conditions of the skin
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- 2-Mercaptoaldehyde dimers and 2,5-dihydrothiophenes from 1,3-oxathiolan-5-ones
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Representative 1,3-oxathiolan-5-ones (6), prepared from 2-mercaptoacids, have been reduced to 2-mercaptoaldehydes 1 with diisobutylaluminum hydride.The aldehydes 1, which appear to exist in several dimeric forms, react with vinyltriphenylphosphonium bromide to give 2,5-dihydrothiophenes.
- McIntosh, John M.,Siddiqui, Maqbool A.
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p. 1872 - 1875
(2007/10/02)
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