6411-34-3Relevant articles and documents
Protein Glycosylation through Sulfur Fluoride Exchange (SuFEx) Chemistry: The Key Role of a Fluorosulfate Thiolactoside
Marra, Alberto,Dong, Jiajia,Ma, Tiancheng,Giuntini, Stefano,Crescenzo, Elisa,Cerofolini, Linda,Martinucci, Marco,Luchinat, Claudio,Fragai, Marco,Nativi, Cristina,Dondoni, Alessandro
, p. 18981 - 18987 (2018)
Protein glycosylation is the most complex post-translational modification process. More than 50 % of human cells proteins are glycosylated, whereas bacteria such as E. coli do not have this modification machinery. Indeed, the carbohydrate residues in natural proteins affect their folding, immunogenicity, and stability toward proteases, besides controlling biological properties and activities. It is therefore important to introduce such structural modification in bioengineered proteins lacking the presence of carbohydrate residues. This is not trivial as it requires reagents and conditions compatible with the protein's stability and reactivity. This work reports on the introduction of lactose moieties in two natural proteins, namely ubiquitin (Ub) and l-asparaginase II (ANSII). The synthetic route employed is based on the sulfur(VI) fluoride exchange (SuFEx) coupling of a lactose tethered arylfluorosulfate (Lact-Ar-OSO2F) with the ?-NH2 group of lysine residues of the proteins. This metal-free click SuFEx reaction relies on the properties of the fluorosulfate employed, which is easily prepared in multigram scale from available precursors and reacts chemoselectively with the ?-NH2 group of lysine residues under mild conditions. Thus, iterative couplings of Lact-Ar-OSO2F to Ub and ANSII, afforded multiple glycosylations of these proteins so that up to three and four Lact-Ar-OSO2 groups were introduced in Ub and ANSII, respectively, via the formation of a sulfamoyl (OSO2-NH) linkage.
Nickel Hydride Catalyzed Cleavage of Allyl Ethers Induced by Isomerization
Kathe, Prasad M.,Berkefeld, Andreas,Fleischer, Ivana
supporting information, p. 1629 - 1632 (2021/02/09)
This report discloses the deallylation of O - and N -allyl functional groups by using a combination of a Ni-H precatalyst and excess Bronsted acid. Key steps are the isomerization of the O - or N -allyl group through Ni-catalyzed double-bond migration followed by Bronsted acid induced O/N-C bond hydrolysis. A variety of functional groups are tolerated in this protocol, highlighting its synthetic value.
Enantioselective Synthesis of 3-Fluorochromanes via Iodine(I)/Iodine(III) Catalysis
Daniliuc, Constantin G.,Gilmour, Ryan,Neufeld, Jessica,Sarie, Jér?me C.,Thiehoff, Christian
supporting information, p. 15069 - 15075 (2020/06/17)
The chromane nucleus is common to a plenum of bioactive small molecules where it is frequently oxidized at position 3. Motivated by the importance of this position in conferring efficacy, and the prominence of bioisosterism in drug discovery, an iodine(I)/iodine(III) catalysis strategy to access enantioenriched 3-fluorochromanes is disclosed (up to 7:93 e.r.). In situ generation of ArIF2 enables the direct fluorocyclization of allyl phenyl ethers to generate novel scaffolds that manifest the stereoelectronic gauche effect. Mechanistic interrogation using deuterated probes confirms a stereospecific process consistent with a type IIinv pathway.
Direct Aryloxylation/Alkyloxylation of Dialkyl Phosphonates for the Synthesis of Mixed Phosphonates
Huang, Hai,Denne, Johanna,Yang, Chou-Hsun,Wang, Haobin,Kang, Jun Yong
supporting information, p. 6624 - 6628 (2018/05/14)
A strategy for the direct functionalization strategy of inertial dialkyl phosphonates with hydroxy compounds to afford diverse mixed phosphonates with good yields and functional-group tolerance has been developed. Mechanistic investigations involving both NMR studies and DFT studies suggest that an unprecedented highly reactive PV species (phosphoryl pyridin-1-ium salt), a key intermediate for this new synthetic transformation, is generated in situ from dialkyl phosphonate in the presence of Tf2O/pyridine.