New di- and triorganotin(IV) derivatives of tyrosinylphenylalanine as models for metal–protein interactions: Synthesis and structural characterization. Crystal structure of Me2Sn(Tyr-Phe)·MeOH
摘要:
New di- and triorganotin(IV) derivatives of tyrosinylphenylalanine (H(2)Tyr-Phe) with general formulae R(2)Sn(Tyr-Phe) where R = Me, n-Bu, n-Oct and Ph, and R(3)'Sn(HTyr-Phe) where R' = Me and Ph have been synthesized. The bonding and coordination behaviour in these derivatives are discussed on the basis of FT-IR, multinuclear (1)H, (13)C and (119)Sn NMR and (119)Sn Mossbauer spectroscopic studies. These investigations suggest that dipeptide in R(2)Sn(Tyr-Phe) acts as dianionic tridentate coordinating through -C(O) O, -NH(2) and (-CO)N(peptide) groups while in case of R(3)'Sn(HTyr-Phe) the ligand acts as monoanionic bidentate coordinating through -C(O)O and -NH(2), and the polyhedron around tin in R(2)Sn(Tyr-Phe) and R'(3)Sn(HTyr-Phe) is a distorted trigonal-bipyramidal. It is further confirmed by the single crystal X-ray structure of Me(2)Sn(Tyr-Phe) center dot MeOH which shows two methyl groups and peptide nitrogen (N(peptide)) in the equatorial positions, while the two axial positions are occupied by the carboxylic oxygen (O(carboxyl)) and the amino nitrogen (N(amino)) atom from the same ligand molecule. One methanol molecule is also present in the asymmetric unit. (C) 2008 Elsevier B.V. All rights reserved.
Protecting group free radical C–H trifluoromethylation of peptides
作者:Naoko Ichiishi、John P. Caldwell、Melissa Lin、Wendy Zhong、Xiaohong Zhu、Eric Streckfuss、Hai-Young Kim、Craig A. Parish、Shane W. Krska
DOI:10.1039/c8sc00368h
日期:——
approaches have been developed to effect the trifluoromethylation of aryl C–H bonds in native peptides either using stoichiometric oxidant or visible light photoredox catalysis. The reported methods are able to derivatize tyrosine and tryptophan sidechains under biocompatible conditions, and a number of examples are reported involving fully unprotected peptides with up to 51 amino acids. The development
Chiral adaptive recognition with sequence specificity of aromatic dipeptides in aqueous solution by an achiral cage
作者:Lin Cheng、Ping Tian、Honghong Duan、Qingfang Li、Xiaowen Song、Anyang Li、Liping Cao
DOI:10.1039/d2sc05854e
日期:——
dipeptides to form 1 : 2 host–guest complexes with high binding affinity (>1010 M−2), especially up to ∼1014 M−2 for TrpTrp. Given the dynamic rotational conformation of TPE units, achiral 1 can exhibit chiral adaptive responses with mirror-symmetrical circular dichroism (CD) and circularly polarized luminescence (CPL) spectra to enantiomeric dipeptides via supramolecular chirality transfer in the host–guest
Chemical isotope labeling-assisted liquid chromatography-mass spectrometry enables sensitive and accurate determination of dipeptides and tripeptides in complex biological samples
作者:Feng-Qing Huang、Yu Wang、Ji-Wen Wang、Dai Yang、Shi-Lei Wang、Yuan-Ming Fan、Raphael N. Alolga、Lian-Wen Qi
DOI:10.1016/j.cclet.2024.109670
日期:2024.2
their unique features and diverse biological functions. Achieving rapid separation and accurate quantification, however, remains a challenge because of their low abundance and the co-existence of numerous structural isomers. In this study, we developed a novel approach using isotopechemical labeling for ultrasensitive determination of di/tripeptides in biologicalsamples. We successfully synthesized a