1.Photostable, amino reactive and water-soluble fluorescent labels based on sulfonated rhodamine with a rigidized xanthene fragment.
Boyarskiy VP1, Belov VN, Medda R, Hein B, Bossi M, Hell SW. Chemistry. 2008;14(6):1784-92.
Highly water soluble fluorescent dyes were synthesized and transformed into new amino reactive fluorescent labels for biological microscopy. To this end, rhodamine 8 (prepared from 7-hydroxy-1,2,3,4-tetrahydroquinoline (7) and phthalic anhydride in 85 % aq. H(3)PO(4)) was sulfonated with 30 % SO(3) in H(2)SO(4) and afforded the water soluble disulfonic acid 3 a (64 %). Amidation of the carboxy group in 3 a with 2-(methylamino)ethanol in the presence of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluroniumPF(6) (-) (HATU) led to alcohol 3 b (66 %), which was transformed into the amino reactive mixed carbonate 3 d with di(N-succinimidyl)carbonate and Et(3)N. Reaction of the carboxy group in 3 a with MeNH(CH(2))(2)CO(2)Me and N,N,N',N'-tetramethyl-O-(N-succinimidyl)-uroniumBF(4) (-) (TSTU) yielded methyl ester 13. After saponification of the aliphatic carboxy group in 13, the compound was converted into NHS-ester 3 e (using HATU and Et(3)N).
2.Improved method for preparing N-hydroxysuccinimide ester-containing polymers for affinity chromatography.
Wilchek M1, Knudsen KL, Miron T. Bioconjug Chem. 1994 Sep-Oct;5(5):491-2.
N,N,N',N'-Tetramethyl(succinimido) uronium tetrafluoroborate is proposed as a reagent of choice for the activation of carboxyl groups and formation of N-hydroxysuccinimide esters on polymers. Unlike conventional methods which generate unstable gels, the reaction is appropriate for hydroxy-containing resins like Sepharose, cellulose, and dextran. The yields of activation and subsequent coupling capacity for ligands and proteins are very high. The respective columns can be used for affinity chromatography and immobilization of proteins.
3.O-(N-succinimidyl)-1,1,3,3-tetramethyluronium tetrafluoroborate-N-hydroxysuccinimide-CuCl2: a facile and reliable system for racemization-free coupling of peptides having a carboxy-terminal N-methylamino acid.
Nishiyama Y1, Ishizuka S, Mori T, Kurita K. Chem Pharm Bull (Tokyo). 2000 Mar;48(3):442-4.
Simultaneous use of N-hydroxysuccinimide (HOSu) and CuCl2 with a HOSu-based uronium coupling reagent, O-(N-succinimidyl)-1,1,3,3-tetramethyluronium tetrafluoroborate, has been found to eliminate the racemization of the carboxy-terminal N-methylamino acid residue during the segment condensation.
4.Synthesis of oligosaccharides with oligoethylene glycol spacers and their conversion into glycoconjugates using N,N,N',N'-tetramethyl(succinimido)uronium tetrafluoroborate as coupling reagent.
Andersson M1, Oscarson S, Ohberg L. Glycoconj J. 1993 Dec;10(6):461-5.
Glycosides of glucose and lactose with di- and tetraethylene glycols, transformed into bifunctional (alcohol, ester) spacer molecules, have been synthesized. After deprotection, these spacer glycosides, containing a free carboxyl group, have been transformed efficiently into glycoconjugates using N,N,N',N'-tetramethyl(succinimido)uronium tetrafluoroborate (TSTU) for the formation of an active ester.
