31972-52-8Relevant articles and documents
Light-responsive peptide [2]rotaxanes as gatekeepers of mechanised nanocontainers
Martinez-Cuezva,Valero-Moya,Alajarin,Berna
, p. 14501 - 14504 (2015)
Novel mechanized silica nanoparticles incorporating a peptide-based molecular shuttle as a photo-responsive interlocked gatekeeper of nanocontainers are described including the uptake and delivery studies of a model cargo.
Side-chain glycylglycine-based polymer for simultaneous sensing and removal of copper(II) from aqueous medium
Choudhury, Neha,Mete, Sourav,Kambalapalli, Srikanth,De, Priyadarsi
, p. 914 - 921 (2018)
Since glycylglycine (Gly-Gly) residue in the N-terminal region of human prion protein, a copper binding protein, binds with Cu(II), N-terminus Gly-Gly side-chain containing water soluble block copolymer was synthesized and used for simultaneous sensing an
Purification-Free Method for Preparing Technetium-99m-Labeled Multivalent Probes for Enhanced in Vivo Imaging of Saturable Systems
Mizuno, Yuki,Uehara, Tomoya,Hanaoka, Hirofumi,Endo, Yota,Jen, Chun-Wei,Arano, Yasushi
, p. 3331 - 3339 (2016)
Metallic radionuclides provide target-specific radiolabeled probes for molecular imaging in radiochemical yields sufficient for administration to subjects without purification. However, unlabeled ligands in the injectate can compete for targeted molecules with radiolabeled probes, which eventually necessitates postlabeling purification. Herein we describe a "1 to 3" design to circumvent the issue by taking advantage of inherent coordination properties of technetium-99m (99mTc). A monovalent RGD ligand possessing an isonitrile as a coordinating moiety (CN-RGD) was reacted with [99mTc(CO)3(OH2)3]+ to prepare [99mTc(CO)3(CN-RGD)3]+ in over 95% radiochemical yields. This complex exhibited higher integrin αvβ3 binding affinity than its unlabeled monovalent ligand, primarily due to its multivalency. This compound visualized a murine tumor without removing unlabeled ligands, while a 99mTc-labeled monovalent probe derived from a monovalent ligand could not. The metal coordination-mediated synthesis of radiolabeled multivalent probes thereby can be a useful approach for preparing ready-to-use target-specific probes labeled with 99mTc and other metallic radionuclides of interest.
Synthesis of Vitamin B12-Antibiotic Conjugates with Greatly Improved Activity against Gram-Negative Bacteria
Zhao, Sheng,Wang, Zhi-Peng,Wen, Xumei,Li, Siyu,Wei, Guoxing,Guo, Jian,He, Yun
, p. 6632 - 6636 (2020)
There is an urgent need to discover new antibiotics and improve the efficacy of known antibiotics against Gram-negative bacteria. "Trojan horse"conjugates are novel and promising antibiotics. Herein we report the design and synthesis of vitamin-B12-ampicillin conjugates, which exhibited more than 500 times improved activity against Escherichia coli compared with ampicillin itself. Our studies demonstrate that the vitamin-B12 uptake pathway could be employed for effective antibiotic delivery and efficacy enhancement.
Dynamic Kinetic Cross-Electrophile Arylation of Benzyl Alcohols by Nickel Catalysis
Guo, Peng,Wang, Ke,Jin, Wen-Jie,Xie, Hao,Qi, Liangliang,Liu, Xue-Yuan,Shu, Xing-Zhong
supporting information, p. 513 - 523 (2021/01/12)
Catalytic transformation of alcohols via metal-catalyzed cross-coupling reactions is very important, but it typically relies on a multistep procedure. We here report a dynamic kinetic cross-coupling approach for the direct functionalization of alcohols. The feasibility of this strategy is demonstrated by a nickel-catalyzed cross-electrophile arylation reaction of benzyl alcohols with (hetero)aryl electrophiles. The reaction proceeds with a broad substrate scope of both coupling partners. The electron-rich, electron-poor, and ortho-/meta-/para-substituted (hetero)aryl electrophiles (e.g., Ar-OTf, Ar-I, Ar-Br, and inert Ar-Cl) all coupled well. Most of the functionalities, including aldehyde, ketone, amide, ester, nitrile, sulfone, furan, thiophene, benzothiophene, pyridine, quinolone, Ar-SiMe3, Ar-Bpin, and Ar-SnBu3, were tolerated. The dynamic nature of this method enables the direct arylation of benzylic alcohol in the presence of various nucleophilic groups, including nonactivated primary/secondary/tertiary alcohols, phenols, and free indoles. It thus offers a robust alternative to existing methods for the precise construction of diarylmethanes. The synthetic utility of the method was demonstrated by a concise synthesis of biologically active molecules and by its application to peptide modification and conjugation. Preliminary mechanistic studies revealed that the reaction of in situ formed benzyl oxalates with nickel, possibly via a radical process, is an initial step in the reaction with aryl electrophiles.
Synthesis of Histidine-Containing Oligopeptides via Histidine-Promoted Peptide Ligation
Huang, Kai-Jin,Huang, Yi-Chen,Lin, Yuya A.
, p. 400 - 403 (2018/02/21)
Histidine-containing peptides are valuable therapeutic agents for a treatment of neurodegenerative diseases. However, the synthesis of histidine-containing peptides is not trivial due to the potential of imidazole sidechain of histidine to act as a nucleophile if unprotected. A peptide ligation method utilizing the imidazole sidechain of histidine has been developed. The key imidazolate intermediate that acts as an internal acyl transfer catalyst during ligation is generated by deprotonation. Transesterification with amino acids or peptides tethered with C-terminal thioester followed by N→N acyl shifts led to the final ligated products. A range of histidine-containing dipeptides could be synthesized in moderate to good yields via this method without protecting the imidazole sidechain. The protocol was further extended to tripeptide synthesis via a long-range N→N acyl transfer, and tetrapeptide synthesis.