deprotectionkineticsmethioninescavengerstrifluoroacetic acidtryptophantyrosineThe trifluoroacetic acid-mediated removal of t-butyl groups in protected amino acids leads to the formation of t-butyl trifluoroacetate. This t-butyl ester alkylates in trifluoroacetic acid methionine and tryptophan. The t-butyl ...
deprotectionkineticsmethioninescavengerstrifluoroacetic acidtryptophantyrosineThe trifluoroacetic acid-mediated removal of t-butyl groups in protected amino acids leads to the formation of t-butyl trifluoroacetate. This t-butyl ester alkylates in trifluoroacetic acid methionine and tryptophan. The t-butyl ...
Deprotection of Boc groups in the presence of tert-butyl esters was achieved by using concentrated H2SO4 (1.5–3.0 equiv.) in tBuOAc or MeSO3H (1.5–3.0 eq... LS Lin,T Lanza,SED Laszlo,... - 《Tetrahedron Letters》 被引量: 74发表: 2000年 ...
After trifluoroacetic acid (TFA) deprotection, the corresponding amines 6a, 6b were coupled with the adenosine derivative 7 31 in the presence of EDC hydrochloride as an activating agent. The obtained derivatives 8a,8b were finally subjected to acidic deprotection to give the desired compounds 1i ...
Deprotection The terbutyloxycarbonyl group, which temporarily protects the N-terminal end of the peptide on the resin, is cleaved by the action of a 40% trifluoroacetic acid solution in dichloromethane for 20 minutes with stirring. The resin is washed with: ...
butyl 3-fluoro-4-(((2,3,4,5-tetrafluoro-N-isopropylphenyl)sulfonamido)methyl)benzoate (4, 76%). Acid-mediated hydrolysis of the carboxylate ester generated the free carboxylic acid product (5, 92%), which coupled to tetrahydropyranyl (THP) (6, 71%). A final deprotection using 4 M ...
Characterization of di-tert-butyl ((S)-2-(((9H-fluoren-9-yl)methoxy)carbonyl)amino)-4-(tert-butoxy)-4-ox obutanoyl)-L-glutamate (HT-A). Obtained from Fmoc-L-aspartic acid β-tert-butyl ester by method A as a white powder; m.p. 116.6–116.9 ◦C; Yield: 85.8%; 1H-NMR (500...
7,100.1,118.0,197.5,209.0 溶剂：氯仿 [Last edited by 齐君 on 2012-8-23 at 21:29]...
摘要: NEW MATERIAL:A cephalosporin analog of formula I (X is acyl group; Hal is halogen) R is carboxylic acid or ester thereof), and its salt. EXAMPLE:tert-Butyl. ester of (+ or -) cis-7-(2-phenyl-2-tert-butyloxycarbonylaminoacetamido)-3-chloro-1-azab icyclo [4.2.0] oct-2-en-...
The hydroxyl group of this compound was then protected by the reaction with di-tert-butyl dicarbonate ester (DBDC) in the presence of 4-dimethylaminopyridine (DMAP) as catalyst to give t-butyloxy carbonyl (tBOC) protected HHPCP. Fourier-transform infrared spectroscopy (FT-IR) and proton ...