A Universal Procedure for the [18F]Trifluoromethylation of Aryl Iodides and Aryl Boronic Acids with Highly Improved Specific Activity

AbstractIn this manuscript we describe the oxidative fluorination of aryl phosphorothiolates to access Ar-SF4Cl compounds. These compounds serve as precursors for the highly coveted Ar-SF5 compounds. The use of phosphorothiolates as starting materials permits access to Ar-SF4Cl from a wide variety of available starting materials, namely boronic acids, diazonium salts, aryl iodides, thiophenols, or simple arenes. The protocol has been demonstrated for >10 examples and showed good tolerance to various functional groups. Finally, we demonstrated that AgBF4 can be used as a fluorinating agent, affording good yields of an Ar-SF5.

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Catalyzed C–C Coupling of Aryl Iodides and Boronic Acids

ISRN Organic Chemistry ◽

10.5402/2012/814247 ◽

2012 ◽

Vol 2012 ◽

pp. 1-4

Author(s):

Payal Malik ◽

Debashis Chakraborty

Keyword(s):

Functional Group ◽

Bond Formation ◽

Coupling Reaction ◽

Boronic Acids ◽

Carbon Bond ◽

Aryl Iodides ◽

Carbon Carbon Bond ◽

Wide Range

An efficient La2O3-catalyzed new route for the carbon-carbon bond formation in particular, symmetrical and unsymmetrical biphenyls has been developed, which proceeds through carbon-carbon coupling reaction of aryl iodides with boronic acids. The reaction provided the desired products in moderate-to-good yields with a wide range of functional group tolerance.

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The Morphology of the Rat Kidney Following Folic Acid Administration

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067996 ◽

1970 ◽

Vol 28 ◽

pp. 200-201

Author(s):

Aline Byrnes ◽

Elsa E. Ramos ◽

Minoru Suzuki ◽

E.D. Mayfield

Keyword(s):

Folic Acid ◽

De Novo ◽

Specific Activity ◽

Rat Kidney ◽

Present Report ◽

Intracellular Localization ◽

Male Rats ◽

Renal Hypertrophy ◽

Electron Microscopic ◽

Biochemical Alterations

Renal hypertrophy was induced in 100 g male rats by the injection of 250 mg folic acid (FA) dissolved in 0.3 M NaHCO3/kg body weight (i.v.). Preliminary studies of the biochemical alterations in ribonucleic acid (RNA) metabolism of the renal tissue have been reported recently (1). They are: RNA content and concentration, orotic acid-c14 incorporation into RNA and acid soluble nucleotide pool, intracellular localization of the newly synthesized RNA, and the specific activity of enzymes of the de novo pyrimidine biosynthesis pathway. The present report describes the light and electron microscopic observations in these animals. For light microscopy, kidney slices were fixed in formalin, embedded, sectioned, and stained with H & E and PAS.

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Synthesis of S-aryl thioesters via palladium-catalyzed thiocarbonylation of aryl iodides and aryl sulfonyl hydrazides

Organic Chemistry Frontiers ◽

10.1039/d0qo00748j ◽

2020 ◽

Vol 7 (19) ◽

pp. 2938-2943

Author(s):

Yeojin Kim ◽

Kwang Ho Song ◽

Sunwoo Lee

Keyword(s):

Aryl Iodide ◽

Aryl Iodides ◽

Palladium Catalyzed

Aryl sulfonyl hydrazide reacted with aryl iodide in the presence of CO to give the corresponding S-aryl thioesters.

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Palladium-catalyzed carbonylative transformation of aryl iodides and sulfonyl chlorides: convenient access to thioesters

Organic Chemistry Frontiers ◽

10.1039/d0qo00158a ◽

2020 ◽

Vol 7 (6) ◽

pp. 885-889 ◽

Cited By ~ 2

Author(s):

Xinxin Qi ◽

Zhi-Peng Bao ◽

Xiao-Feng Wu

Keyword(s):

Sulfonyl Chlorides ◽

Aryl Iodides ◽

Palladium Catalyzed ◽

Convenient Access

A palladium-catalyzed carbonylative transformation of aryl iodides and sulfonyl chlorides to thioesters has been studied.

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Assays for Phospholipid-Dependent Formation of Thrombin and Xa: A Potential Method for Quantifying Lupus Anticoagulant Activity

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646437 ◽

1991 ◽

Vol 66 (04) ◽

pp. 453-458 ◽

Cited By ~ 15

Author(s):

John T Brandt

Keyword(s):

Specific Activity ◽

Anticoagulant Activity ◽

Factor Xa ◽

Clinical Importance ◽

Potential Method ◽

Quantitative Expression ◽

Increased Risk ◽

Apparent Association

SummaryLupus anticoagulants (LAs) are antibodies which interfere with phospholipid-dependent procoagulant reactions. Their clinical importance is due to their apparent association with an increased risk of thrombo-embolic disease. To date there have been few assays for quantifying the specific activity of these antibodies in vitro and this has hampered attempts to purify and characterize these antibodies. Methods for determining phospholipid-dependent generation of thrombin and factor Xa are described. Isolated IgG fractions from 7 of 9 patients with LAs were found to reproducibly inhibit enzyme generation in these assay systems, permitting quantitative expression of inhibitor activity. Different patterns of inhibitory activity, based on the relative inhibition of thrombin and factor Xa generation, were found, further substantiating the known heterogeneity of these antibodies. These systems may prove helpful in further purification and characterization of LAs.

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Extraction of Protein-Bound ATP and ADP from Human Platelets in Plasma

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645211 ◽

1990 ◽

Vol 63 (02) ◽

pp. 286-290 ◽

Cited By ~ 3

Author(s):

Christina Beurling-Harbury ◽

Pehr B Harbury

Keyword(s):

Specific Activity ◽

Platelet Rich Plasma ◽

Binding Protein ◽

Human Platelets ◽

Luciferase Assay ◽

First Time ◽

Plasma Extraction

SummaryActin is the major ATP and ADP binding protein in platelets, 0.9–1.3 nmol/108 cells, 50–70% in the unpolymerized state. The goal of these experiments was to develop a method for extracting all protein-bound ATP and ADP from undisturbed platelets in plasma. Extraction of actin-bound ADP is routine while extraction of actin-bound ATP from platelets in buffer has been unsuccessful. Prior to extraction the platelets were exposed to 14-C adenine, to label the metabolic and actin pools of ATP and ADP. The specific activity was determined from the actin-bound ADP in the 43% ethanol precipitate. Sequential ethanol and perchlorate extractions of platelet rich plasma, and the derived supernatants and precipitates were performed. ATP concentrations were determined with the luciferase assay, and radioactive nucleotides separated by TLC. A total of 1.18 nmol/108 cells of protein-bound ATP and ADP was recovered, 52% ATP (0.61 nmol). The recovery of protein-bound ADP was increased from 0.3 to 0.57 nmol/108 cells. This approach for the first time successfully recovered protein bound ATP and ADP from platelets in a concentration expected for actin.

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On the Preparation of Bovine α-Thrombin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646669 ◽

1978 ◽

Vol 39 (01) ◽

pp. 193-200 ◽

Cited By ~ 7

Author(s):

Erwin F Workman ◽

Roger L Lundblad

Keyword(s):

Immobilized Enzyme ◽

Catalytic Properties ◽

Specific Activity ◽

Guanidine Hydrochloride ◽

Low Molecular Weight ◽

Reversible Process ◽

Gel Beads ◽

Tissue Thromboplastin ◽

C 50 ◽

Hydrolysis Of

SummaryAn improved method for the preparation of bovine α-thrombin is described. The procedure involves the activation of partially purified prothrombin with tissue thromboplastin followed by chromatography on Sulfopropyl-Sephadex C-50. The purified enzyme is homogeneous on polyacrylamide discontinuous gel electrophoresis and has a specific activity toward fibrinogen of 2,200–2,700 N.I.H. U/mg. Its stability on storage in liquid media is dependent on both ionic strenght and temperature. Increasing ionic strength and decreasing temperature result in optimal stability. The denaturation of α-thrombin by guanidine hydrochloride was found to be a partially reversible process with the renatured species possessing properties similar to “aged” thrombin. In addition, the catalytic properties of a-thrombin covalently attached to agarose gel beads were also examined. The activity of the immobilized enzyme toward fibrinogen was affected to a much greater extent than was the hydrolysis of low molecular weight, synthetic substrates.

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