116821-47-7Relevant articles and documents
Syntheses and transglutaminase-catalyzed incorporation of novel spin-labeled primary amines into proteins
Narasimhan, Chakravarthy,Lai, Ching-San,Joseph, Joy
, p. 50 - 58 (1996)
A series of spin-labeled primary amine derivatives, namely, 2,2,6,6-tetramethyl-piperidinyl-oxyl-4-amidoalkylamines with varying alkyl chain lengths, have been synthesized. The spin-labeled primary amine-with a tetramethylene or a pentamethylene chain covalently modifies human plasma fibronectin with a stoichiometry of 0.97-to-1.0 (probe-to-subunit) in the presence of coagulation factor XIIIa. The labels with two or one methylene chain also similarly modify fibronectin, but with a stoichiometry of only about 0.3-0.4 per subunit. The spin-labeled primary amine with a trimethylene chain does not label fibronectin. The labeling site appears to be the glutamine-3 residue at the amino-terminal region of fibronectin. Electron spin resonance studies show that the bound labels are partially immobilized with an effective rotational correlation time of 0.4-0.6 ns. The spin-labeled primary amine with tetramethylene chain also is shown to covalently incorporate into bee venom melittin in the presence of guinea-pig liver transglutaminase. The syntheses of the various spin-labeled primary amines and their applications in the study of structure and dynamics of different proteins and peptides are discussed. The observations from this study suggest that these spin-labeled primary amines have potentially wide application as structural probes.
Enzymatic removal of carboxyl protecting groups. 1. Cleavage of the tert-butyl moiety
Schmidt, Marlen,Barbayianni, Efrosini,Fotakopoulou, Irene,Hoehne, Matthias,Constantinou-Kokotou, Violetta,Bornscheuer, Uwe T.,Kokotos, George
, p. 3737 - 3740 (2005)
(Chemical Equation Presented) A recent discovery that a certain amino acid motif (GGG-(A)X-motif) in lipases and esterases determines their activity toward tertiary alcohols prompted us to investigate the use of these biocatalysts in the mild and selective removal of tert-butyl protecting groups in amino acid derivatives and related compounds. An esterase from Bacillus subtilis (BsubpNBE) and lipase A from Candida antarctica (CAL-A) were identified as the most active enzymes, which hydrolyzed a range of tert-butyl esters of protected amino acids (e.g., Boc-Tyr-OtBu, Z-GABA-OtBu, Fmoc-GABA-O tBu) in good to high yields and left Boc, Z, and Fmoc-protecting groups intact.
4-Methyltrityl-Protected Pyrrole and Imidazole Building Blocks for Solid Phase Synthesis of DNA-Binding Polyamides
Heinrich, Benedikt,Vázquez, Olalla
, p. 533 - 536 (2020)
DNA-binding polyamides are synthetic oligomers of pyrrole/imidazole units with high specificity and affinity for double-stranded DNA. To increase their synthetic diversity, we report a mild methodology based on 4-methyltrityl (Mtt) solid phase peptide synthesis (SPPS), whose building blocks are more accessible than the standard Fmoc and Boc SPPS ones. We demonstrate the robustness of the approach by preparing and studying a hairpin with all precursors. Importantly, our strategy is orthogonal and compatible with sensitive molecules and could be readily automated.
Dicyclohexylurea derivatives of amino acids as dye absorbent organogels and anion sensors
Roy, Karabi,Ghosh, Suvankar,Chetia, Monikha,Satpati, Priyadarshi,Chatterjee, Sunanda
, p. 3026 - 3039 (2019/03/21)
Dicyclohexyl urea (DCU) derivatives of amino acids Fmoc-Phe-DCU (M1), Fmoc-Phg-DCU (M2) and Fmoc-Gaba-DCU (M3) have been shown to form phase selective, thermoreversible and mechanically robust gels in a large range of organic solvents. This is the first report of low molecular weight gelators (LMWG) from DCU derivatives of amino acids. The self-assembly mechanism of the organogels has been probed using concentration dependent 1H NMR, DMSO titration 1H NMR, fluorescence, FTIR, PXRD and FESEM techniques. Self-assembly leading to gelation process is mainly driven by hydrophobicity and π-π stacking interactions in between Fmoc groups. Interestingly, the gels can absorb several kinds of organic dyes efficiently and can be reused for dye absorption for multiple cycles. Additionally, M1-M3 act as sensors for anions like fluoride, acetate and hydroxide, for which they have specific fluorescence response. Gel formation by M1-M3 is completely arrested in the presence of fluoride. The possible binding mode of fluoride has been delineated using DFT studies. Calculations suggest, involvement of urea NH in a six membered intramolecular hydrogen bond, rendering it unavailable for fluoride binding. Backbone -NH of the amino acids of M1-M3 is responsible for fluoride binding. The reported small, economically viable, synthetically facile molecules not only enrich the repertoire of LMWG molecules, but can have multifaceted applications.