A novel copper NHC complex enables mild compatible aqueous alkylation at the O6-G position of guanine.
一种新型铜NHC配合物实现了对鸟嘌呤的O6-G位置进行温和兼容的水相烷基化。
The synthetic tuning of clickable pH responsive cationic polypeptides and block copolypeptides
作者:Amanda C. Engler、Daniel K. Bonner、Hilda G. Buss、Eva Y. Cheung、Paula T. Hammond
DOI:10.1039/c1sm05064h
日期:——
A series of pH responsive synthetic polypeptides has been developed based on an N-carboxyanhydride ring opening polymerization combined with a facile and versatile click chemistry. Poly(γ-propargyl L-glutamate) (PPLG) homopolymers and poly(ethylene glycol-b-γ-propargyl L-glutamate) (PEG-b-PPLG) block copolymers were substituted with various amine moieties that range in pKa and hydrophobicity, providing the basis for a library of new synthetic structures that can be tuned for specific interactions and responsive behaviors. These amine-functionalized polypeptides have the ability to change solubility, or reversibly self-assemble into micelles with changes in the degree of ionization; they also adopt an α-helical structure at biologically relevant pHs. Here we characterize the pH responsive behavior of the new polypeptides and the hydrolysis of the ester containing amine side chains. We examine the reversible micellization with block copolymers of the polypeptides and nucleic acid encapsulation that demonstrate the potential use of these materials for systemic drug and gene delivery.
Identification of Adenosine-to-Inosine RNA Editing with Acrylonitrile Reagents
作者:Ying Li、Matthias Göhl、Ke Ke、Christopher D. Vanderwal、Robert C. Spitale
DOI:10.1021/acs.orglett.9b02929
日期:2019.10.4
New chemical probes have been designed to facilitate the identification of adenosine-to-inosine (A-to-I) edited RNAs. These reagents combine a conjugate acceptor for selective inosine covalent modification with functional groups for bioorthogonal biotinylation. The resulting biotinylated RNA was enriched and verified with RT-qPCR. This powerful chemical approach provides new opportunities to identify
one-pot Staudinger/aza-Wittig/Castagnoli-Cushman reaction sequence for a series of azido aldehydes and homophthalic anhydrides is described. The reaction proceeded at room temperature and delivered novel polyheterocycles related to the natural product realm in high yields and high diastereoselectivity. The methodology has been extended to three other cyclic anhydrides. These further unravel the potential