The orderly migration of various white blood cell types to inflammatory sites is a highly regulated process that involves a diversity of adhesion and signaling molecules. This cellular influx is initiated by relatively low affinity interactions that allow for leukocytes to roll along the vascular surfa ce. This rolling phe­ nomenon is mediated by adhesive interactions between lectin containing ad­ hesion molecules, termed selectins, on both the vascular endothelium and leukocytes, and car bohydrate ligands immobilized on mucin-like scaffolds. This adhesion allows for a rapid recognition of various cell types under the conditions of vascular flow, with the result that inflammatory cells are spe­

Interactions and the initiation of the inflammatory response

The sulfinatodehalogenation reaction represents one of the most important methodologies to incorporate fluorine into organic molecules. Using inexpensive sulfur-containing reactants such as Na2S2O4 under mild conditions, per- and polyfluoroalkyl halides (RFX, X = Br, I, CCl3) can be transformed smoothly into the corresponding sulfinate salts. This method is also used for the perfluoroalkylation of alkenes, dienes, alkynes and aromatics. Notably, after 1998, the sulfinatodehalogenation of perfluoroalkyl chlorides (RFCl) has been realized by using dimethylsulfoxide (DMSO) as a solvent instead of CH3CN/H2O in the Na2S2O4/NaHCO3 initiation system. Perfluoroalkyl chlorides, ethyl chlorofluoroacetates and chlorodifluoroacetates, and even nonfluorinated compounds, such as ethyl chloro- or dichloroacetates and chloroform, were either converted into the corresponding sulfinate salts or alkylated alkenes, alkynes and aromatics (including porphyrins). The sulfinatodehalogenation reaction has remarkable advantages. With the increasing demands to utilize the unique properties of fluorine and fluorinated functional groups in medicinal, agricultural and material sciences, we believe that there will continue to be useful developments in sulfinatodehalogenation chemistry and it will be applied more widely in the future.

Progress in fluoroalkylation of organic compounds via sulfinatodehalogenation initiation system

for Organic Synthesis Valentine G. Nenajdenko,*,†,§ Vasiliy M. Muzalevskiy,† and Aleksey V. Shastin†,‡ †Department of Chemistry, Moscow State University, Leninskie Gory, Moscow 119992, Russia ‡The Institute of Problems of Chemical Physics of the Russian Academy of Sciences (IPCP RAS), Chernogolovka, Moscow Region 142432, Russia A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), 119991, GSP-1, Moscow, V-334, Vavilova St. 28, Russia

Polyfluorinated ethanes as versatile fluorinated C2-building blocks for organic synthesis.

One way to introduce fluorine into a molecule is through fluoroalkylation reactions. Transition-metal catalysts play an increasing role in selectively incorporating fluoroalkyl groups into organic molecules, especially during the late stages of a synthesis. In this review, we highlight the development of methodologies to incorporate the (CF2H), (CF2R), and ((CF2)n) functionalities into organic substrates by transition-metal complexes. Also discussed are the structural changes that can arise when repeating arrays of (CF2) or (CH2CF2) units are introduced into a single molecule through polydifluoromethylenation reactions.

Transition-Metal-Catalyzed Difluoromethylation, Difluoromethylenation, and Polydifluoromethylenation Reactions

UDP-Galactopyranose mutase (UGM) is a flavin-containing enzyme that catalyzes the reversible conversion of UDP-galactopyranose (UDP-Galp) to UDP-galactofuranose (UDP-Galf) and plays a key role in the biosynthesis of the mycobacterial cell wall galactofuran. A soluble, active form of UGM from Mycobacterium tuberculosis (MtUGM) was obtained from a dual His6-MBP-tagged MtUGM construct. We present the first complex structures of MtUGM with bound substrate UDP-Galp (both oxidized flavin and reduced flavin). In addition, we have determined the complex structures of MtUGM with inhibitors (UDP and the dideoxy-tetrafluorinated analogues of both UDP-Galp (UDP-F4-Galp) and UDP-Galf (UDP-F4-Galf)), which represent the first complex structures of UGM with an analogue in the furanose form, as well as the first structures of dideoxy-tetrafluorinated sugar analogues bound to a protein. These structures provide detailed insight into ligand recognition by MtUGM and show an overall binding mode similar to those reported for...

/pdf/structural-basis-of-ligand-binding-to-udp-galactopyranose-32ztugh6rc.pdf

Structural Basis of Ligand Binding to UDP-Galactopyranose Mutase from Mycobacterium tuberculosis Using Substrate and Tetrafluorinated Substrate Analogues

Enantioselective synthesis of tetrafluorinated glucose and galactose.

A perfluoroalkylidene lithium mediated cyclisation approach for the enantioselective synthesis of a tetrafluorinated aldose (ribose) and of a tetrafluorinated ketose (fructose), both in the furanose and in the pyranose form, is described.

Enantioselective synthesis of tetrafluorinated ribose and fructose.

Heavily fluorinated carbohydrates as enzyme substrates: oxidation of tetrafluorinated galactose by galactose oxidase

Carbohydrates typically have low affinities to protein binding sites, and the development of carbohydrate mimetics with improved binding is therefore of interest. Tetrafluorination of monosaccharides is one of the strategies currently under investigation for that purpose. The synthesis of the required tetrafluorinated monosaccharides is achieved by a fluorinated building block approach. The enantioselective synthesis of tetrafluorinated hexose derivatives is described here, in both pyranose and furanose forms. In particular, the optimization of the enantioselective synthesis of the previously reported 2,3-dideoxy-2,2,3,3-tetrafluoro-d-threo-hexopyranose 3, 2,3-dideoxy-2,2,3,3-tetrafluoro-d-threo-hexofuranose 4, and 2,3-dideoxy-2,2,3,3-tetrafluoro-d-erythro-hexopyranose 5 is described as is the synthesis of two novel sugar derivatives, 3,4-dideoxy-3,3,4,4-tetrafluoro-d-threo-hexopyranose 6 and 3,4-dideoxy-3,3,4,4-tetrafluoro-d-erythro-hexopyranose 7. The key step of all syntheses is a perfluoroalkyl lithiu...

https://pubs.acs.org/doi/pdf/10.1021/acs.joc.6b00302

Roxana S. Timofte

Papers

Enantioselective synthesis of tetrafluorinated glucose and galactose.

Enantioselective synthesis of tetrafluorinated ribose and fructose.

Heavily fluorinated carbohydrates as enzyme substrates: oxidation of tetrafluorinated galactose by galactose oxidase

Enantioselective Synthesis of Dideoxy-tetrafluorinated Hexoses.

Preparation of silane-grafted pellets: silica bound reagents in a very convenient form