摘要：
Poly(ethylene glycol)s (PEGs) are the most used polymers in biomedicine, and their so-called “stealth” effects are the “gold standard” for biomaterials. However, the polydispersity in regular PEGs hampers their biomedical application, especially in modification of small molecular drugs (SMDs). To address this issue, many synthetic strategies for monodisperse PEGs (M-PEGs) have recently been developed. More importantly, M-PEGs have been successfully employed to modify SMDs, and the crucial roles of M-PEGs in PEGylated SMDs have been discovered in many cases. Herein we summarize the strategies for the synthesis of M-PEGylated SMDs, including Movantik, NKTR-181, polidocanol, propofol, and camptothecin, and the important roles of M-PEGs in optimizing the physicochemical properties, bioavailability, and therapeutic efficacy of SMDs. M-PEGylation is a convenient and effective strategy to develop novel SMDs, especially on the basis of marketed drugs. This review may shed light on the rational design and efficient synthesis of new M-PEGylated SMDs.
作者机构：
[Jiang, Zhong-Xing; Wang, Xuemeng; Yang, Zhigang] Wuhan Univ, Wuhan, Peoples R China.;[Li, Yu; Zhou, Xin; Chen, Shizhen] Chinese Acad Sci, Wuhan, Peoples R China.;[Wu, Tingjuan; Zheng, Xing] Univ South China, Hengyang, Peoples R China.
通讯机构：
[Zhou, Xin] C;[Jiang, Zhong-Xing] W;Chinese Acad Sci, Wuhan, Peoples R China.;Wuhan Univ, Wuhan, Peoples R China.
摘要：
In biomedicine, PEGylation is one of the most successful strategies to modify the physicochemical and biological properties of peptides, proteins, and other biomacromolecules. Because of the polydisperse nature of regular PEGs and limited PEGylation strategies, it is challenging to quantitatively fine-tune and accurately predict the properties of biomacromolecules after PEGylation. However, such fine-tuning and prediction may be crucial for their biomedical applications. Herein, some monodisperse PEGylation strategies, including backbone PEGylation, side-chain PEGylation, and highly branched PEGylation, have been developed. In a comparative fashion, the impact of PEGylation strategies and monodisperse PEG sizes on the physicochemical and biological properties, including lipophilicity, thermosensitivity, biocompatibility, plasma stability, and drug delivery capability, of peptidic polymers has been quantitatively studied. It was found that the physicochemical and biological properties of PEGylated peptidic polymers can be quantitatively fine-tuned and accurately predicted through these monodisperse PEGylation strategies. After the comparative study, a side-chain monodisperse PEGylated peptidic polymer was chosen as fluorine-19 magnetic resonance and fluorescence dual-imaging traceable drug delivery vehicle. Our study may not only promote the transformation of PEGylation from an empirical technology to a quantitative science but also shed light on the rational design of PEGylated biomaterials and pharmaceutics.
关键词：
drug delivery;imaging;liposome;polyethylene glycols;stimuli-responsive biomaterials
摘要：
Monodisperse polyethylene glycols-modified (M-PEGylated) biomaterials exhibit high structural accuracy, biocompatibility, and fine-tunable physicochemical properties. To develop "smart" drug delivery systems in a controllable and convenient manner, a peptidic M-PEG "comb" with fluorinated L-lysine side chains and a fluorescent N-terminal is conveniently prepared as a (19) F magnetic resonance imaging ((19) F MRI) and fluorescence dual-imaging traceable and thermo-responsive "add-on" module for liposomal theranostics in cancer therapy. The peptidic M-PEG "comb" has high biocompatibility, thermo-responsivity with a sharp lower critical solution temperature, an aggregation-induced emission fluorescence, and high (19) F MRI sensitivity. As a highly branched amphiphile, it self-assembles and firmly anchors on the doxorubicin-loaded liposomal nanoparticles, which M-PEGylates the liposomes and facilitates the thermo-responsive drug release and drug tracking with dual-imaging technologies. In a rodent xenograft model of human liver cancer HepG2 cells, the M-PEGylated liposomes exhibit long in vivo half time, low toxicity, high tumor accumulation, "hot spot" (19) F MRI, and therapeutic efficacy. With accurately programmable chemical structure, fine-tunable physicochemical and biological properties to meet the demands of diagnosis, drug delivery, and therapy, the M-PEG "comb" is promising as a versatile "add-on" module for rapid and convenient formulation of various "smart" theranostics.
摘要：
<jats:title>Abstract</jats:title><jats:p>Resveratrol is a natural phytoestrogen produced by plants to protect themselves from injury, UV irradiation, and fungal attack. The main active structure is <jats:italic>E</jats:italic>‐resveratrol, which has many pharmacological activities. As the structure of resveratrol is similar to the natural estrogen 17β‐estradiol and the synthetic estrogen <jats:italic>E</jats:italic>‐diethylstilbestrol, resveratrol is used in reducing the incidence of breast cancer. However, the therapeutic application of resveratrol is limited due to its low bioavailability. To improve its bioavailability and pharmacological activity, some resveratrol derivatives have been designed and synthesized by substitutions of methoxy, hydroxyl, and other functional groups or heterocyclic esterification either on the “A” or “B” ring, and double bonds were replaced by imine bonds and isometric heterocycles such as naphthyl and imidazole, or synthetic resveratrol oligomers. The structures, synthetic routes, and evaluation of the biological activities of these compounds are discussed. These are aimed at providing some references for the study of resveratrol derivatives in anti‐breast cancer treatment.</jats:p>
通讯机构：
[Zheng, Xing; Zhang, Xingang] U;Univ South China, Hunan Prov Cooperat Innovat Ctr Mol Target New Dr, Hunan Prov Key Lab Tumor Microenvironm Respons Dr, Inst Pharm & Pharmacol, Hengyang 421001, Hunan, Peoples R China.;Univ Chinese Acad Sci, Key Lab Organofluorine Chem, Ctr Excellence Mol Synth, Shanghai Inst Organ Chem,Chinese Acad Sci, 345 Lingling Lu, Shanghai 200032, Peoples R China.
摘要：
A nickel-catalyzed tandem reaction of N-vinylamides with arylboronic acids and bromodifluoroacetate has been developed. The use of amide carbonyl as a chelating group efficiently furnishes a series of protected alpha,alpha-difluoro-gamma-amino acid esters. The reaction can also extend to bromoacetate and 2-bromomalonate. The advantages of this protocol are high functional group tolerance and a broad substrate scope, including a variety of N-vinylamides. In particular, the use of removable amide carbonyl groups provides potential opportunities for applications in peptide chemistry and protein engineering.
通讯机构：
[Zheng, Xing] U;[Wang, Ruowen] S;Univ South China, Hunan Prov Cooperat Innovat Ctr Mol Target New Dr, Inst Pharm & Pharmacol, Hengyang 421001, Hunan, Peoples R China.;Shanghai Jiao Tong Univ, Renji Hosp, Sch Med, Inst Mol Med,State Key Lab Oncogenes & Related Ge, Shanghai 00240, Peoples R China.
关键词：
Amino acids;Prodrug;SuFEx;Fluorosulfate
摘要：
Sulfur (VI) Fluoride Exchange (SuFEx) chemistry is proposed as a new generation of click chemistry with potential in drug discovery and biological study. Herein we report a simple and convenient approach to synthesize amino acid derivatives functionalized with aryl fluorosulfonyl group from a simple building block. Promoted by 1,1'-Carbonyldiimidazole (CDI), methyl protected amino acids and other amines were efficiently functionalized with SO2F by the reaction with 4-((fluorosulfonyl)oxy)benzoic acid giving fluorosulfonylated amides (FSAs) as products. We also demonstrated that FSAs are useful building blocks in drug discovery. The conjugation of FSA with pharmaceutical phenols by SuFEx efficiently introduced amino acid moiety into target molecule, providing a series of prodrugs with diverse property. (C) 2020 Elsevier Ltd. All rights reserved.
摘要：
Camptothecin, which represents a class of natural products with high anticancer activity, suffers low water solubility which hampers its clinic application. To address this issue, monodisperse polyethylene glycols were employed to modify this class of natural products, including Camptothecin, 10-Hydroxycamptothecin, and SN38. Through selective modification with a series of monodisperse polyethylene glycols, 31 Camptothecin derivatives, including 9 ethers and 22 carbonates, were prepared using a macrocyclic sulfate-based strategy with high efficacy. Monodisperse polyethylene glycols modification provided the Camptothecin derivatives with high purity and fine-tunable water solubility. Through the physicochemical and biological assays, a few novel prodrugs with good solubility, cytotoxicity, and valuable drug release profile were identified as promising anticancer drug candidates.
摘要：
A novel amphiphilic supramolecular polymer (ASP) with rigid linear main chain has been constructed by the co-assembly of a rigid amphiphilic monomer and cucurbit[8]uril (CB[8]) in water, driven by CB[8]-based host-guest interactions. The ASP could further self-assemble into well-defined architectures including nanotubes and 2D films, depending on its concentration. Moreover, pH-responsive behavior of the ASP was also observed. (C) 2019 Elsevier Ltd. All rights reserved.
摘要：
In this study, we investigated the anticancer effects of FS-7, a flavonoid salicylate derivative, in human gastric carcinoma MGC-803 cell line and studied its preliminary anticancer effects. FS-7 displayed greater in vitro cytotoxicity against MGC-803 cell line compared with 5-Fu and had a certain extent of selectivity to cancer cells. The flow cytometry analysis revealed that FS-7 induced apoptosis MGC-803 cells and mainly caused cells arrest in the G2/M phase in a concentration-dependent manner. Additionally, FS-7 inhibited the colony formation and cell migration in a concentration-dependent manner. Notably, FS-7 noticeably down-regulated glycolysis-related protein HIF-1 alpha, HK-II and PFKP expression in a concentration-dependent manner, possibly causing glycolysis inhibition. Importantly, compared with 5-Fu, FS-7 showed better anticancer activity in the MGC-803 xenograft murine tumor models. Collectively, the present study provided a promising anticancer drug candidate for gastric cancer therapy.
摘要：
Flavan-3-ols are a series of natural products widely present in plants and show versatile biological activities. The structures of such compounds are characterized by owing two adjacent chiral centers and three rings. Their interesting structures and promising biological activities have driven increasing research developments toward the preparation of enantioenriched flavan-3-ols. This review summarizes the recent approaches for the asymmetric synthesis of chiral flavan-3-ols from two strategies in the construction of chiral centers. The key steps in the synthetic protocol involve Sharpless asymmetric dihydroxylation, Shi asymmetric epoxidation and Sharpless asymmetric epoxidation.
