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1.
Molecules ; 29(9)2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38731412

ABSTRACT

Skeleton editing has rapidly advanced as a synthetic methodology in recent years, significantly streamlining the synthesis process and gaining widespread acceptance in drug synthesis and development. This field encompasses diverse ring reactions, many of which exhibit immense potential in skeleton editing, facilitating the generation of novel ring skeletons. Notably, reactions that involve the cleavage of two distinct rings followed by the reformation of new rings through ring insertion play a pivotal role in the construction of novel ring skeletons. This article aims to compile and systematize this category of reactions, emphasizing the two primary reaction types and offering a thorough exploration of their associated complexities and challenges. Our endeavor is to furnish readers with comprehensive reaction strategies, igniting research interest and injecting fresh impetus into the advancement of this domain.


Subject(s)
Heterocyclic Compounds , Heterocyclic Compounds/chemistry , Heterocyclic Compounds/chemical synthesis , Molecular Structure , Chemistry Techniques, Synthetic
2.
Org Biomol Chem ; 22(22): 4420-4435, 2024 06 05.
Article in English | MEDLINE | ID: mdl-38775347

ABSTRACT

Over past decades, chiral amides and peptides have emerged as powerful and versatile compounds due to their various biological activities and interesting molecular architectures. Although some chiral condensation reagents have been applied successfully for their synthesis, the introduction of racemization-free methods of amino acid activation have shown lots of advantages in terms of their low cost and low toxicity. In this review, advancements in amide and peptide synthesis using racemization-free coupling reagents over the last 10 years are summarized. Various racemization-free coupling reagents have been applied in the synthesis of enantioselective amides and peptides, including ynamides, allenones, HSi[OCH(CF3)2]3, Ta(OMe)5, Nb(OEt)5, Ta(OEt)5, TCFH-NMI, water-removable ynamides, DBAA, DATB, o-NosylOXY, TCBOXY, Boc-Oxyma, NDTP, 9-silafluorenyl dichlorides, the Mukaiyama reagent, EDC and T3P. The racemization-free reagents described in this review provide an alternative greener option for the asymmetric synthesis of chiral amides and peptides. We hope that this review will inspire further studies and developments in this field.


Subject(s)
Amides , Peptides , Amides/chemistry , Amides/chemical synthesis , Peptides/chemistry , Peptides/chemical synthesis , Stereoisomerism , Chemistry Techniques, Synthetic/methods , Indicators and Reagents/chemistry , Molecular Structure
3.
Nucl Med Biol ; 132-133: 108911, 2024.
Article in English | MEDLINE | ID: mdl-38614036

ABSTRACT

INTRODUCTION: The pretargeting approach consists of in vivo ligation between pre-injected antibodies and low-molecular-weight radiolabeled effectors. The advantage of the pretargeting approach is to improve a tumor-to-background ratio, but the disadvantage is to compromise tumor accumulation. In this study, we applied albumin binder (ALB) to the pretargeting approach to overcome low tumor accumulation. METHODS: We synthesized two novel trifunctional effectors containing an ALB moiety, a chelator, and a different tetrazine and two corresponding effectors without an ALB moiety. Albumin-binding assays and stability assays were performed using 111In-labeled effectors. Measurements of reaction rate constant were conducted using 111In-labeled effectors and anti-HER2 antibody trastuzumab modified by trans-cyclooctene, which drives the click reaction with tetrazine. Biodistribution studies using HER2-expressing tumor-bearing mice were performed with or without the pretargeting approach. RESULTS: In albumin-binding assays, ALB-containing effectors exhibited a marked binding to albumin. Two ALB-containing effectors showed the difference in the reactivity and the slight difference in the stability. In biodistribution studies without the pretargeting approach, two ALB-containing effectors showed different pharmacokinetics in blood retention. With the pretargeting approach, the tumor accumulation was improved by the introduction of ALB and the highest tumor accumulation was observed in using the ALB-containing effector with higher blood retention. CONCLUSION: These results suggest that the application of ALB to the pretargeting approach is effective to improve tumor accumulation, and the structure of tetrazine influences the utility of ALB-containing effectors.


Subject(s)
Chelating Agents , Animals , Mice , Chelating Agents/chemistry , Chelating Agents/chemical synthesis , Tissue Distribution , Cell Line, Tumor , Humans , Chemistry Techniques, Synthetic , Female , Albumins/chemistry , Receptor, ErbB-2/metabolism , Trastuzumab/chemistry , Trastuzumab/pharmacokinetics
4.
Science ; 384(6692): eadl4015, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38603508

ABSTRACT

Therapeutic oligonucleotides are a powerful drug modality with the potential to treat many diseases. The rapidly growing number of therapies that have been approved and that are in advanced clinical trials will place unprecedented demands on our capacity to manufacture oligonucleotides at scale. Existing methods based on solid-phase phosphoramidite chemistry are limited by their scalability and sustainability, and new approaches are urgently needed to deliver the multiton quantities of oligonucleotides that are required for therapeutic applications. The chemistry community has risen to the challenge by rethinking strategies for oligonucleotide production. Advances in chemical synthesis, biocatalysis, and process engineering technologies are leading to increasingly efficient and selective routes to oligonucleotide sequences. We review these developments, along with remaining challenges and opportunities for innovations that will allow the sustainable manufacture of diverse oligonucleotide products.


Subject(s)
Oligonucleotides , Oligonucleotides/chemical synthesis , Oligonucleotides/therapeutic use , Chemistry Techniques, Synthetic
5.
Ultrason Sonochem ; 105: 106858, 2024 May.
Article in English | MEDLINE | ID: mdl-38564910

ABSTRACT

Zinc sulfide/graphitic Carbon Nitride binary nanosheets were synthesized by using a novel sonochemical pathway with high electrocatalytic ability. The as- obtained samples were characterized by various analytical methods such as Transmission Electron Microscopy (TEM), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS) to evaluate the properties of ZnS@CNS synthesized by this new route. Subsequently, the electrical and electrochemical performance of the proposed electrodes were characterized by using EIS and CV to establish an electroactive ability of the nanocomposites. The complete properties like structural and physical of ZnS@CNS were analyzed. As-prepared binary nanocomposite was applied towards the detection of anticancer drug (flutamide) by various electrochemical methods such as cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometry. The glassy carbon electrode modified with a ZnS@CNS composite demonstrates a remarkable electrocatalytic efficiency for detecting flutamide in a pH 7.0 (PBS). The composite modified electrode shows synergistic effect of ZnS and CNS catalyst. The electrochemical sensing performance of the linear range was improved significantly due to high electroactive sites and rapid electron transport pathways. Crucially, the electrochemical method was successfully demonstrated in biological fluids which reveals its potential real-time applicability in the analysis of drug.


Subject(s)
Antineoplastic Agents , Electrodes , Graphite , Nitrogen Compounds , Sulfides , Ultrasonic Waves , Zinc Compounds , Zinc Compounds/chemistry , Sulfides/chemistry , Antineoplastic Agents/chemistry , Graphite/chemistry , Flutamide/analysis , Flutamide/chemistry , Electrochemical Techniques/methods , Chemistry Techniques, Synthetic , Electrochemistry , Limit of Detection , Catalysis , Nanocomposites/chemistry , Nanostructures/chemistry
6.
J Labelled Comp Radiopharm ; 67(5): 186-196, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38661253

ABSTRACT

Malaria continues to be a serious and debilitating disease. The emergence and spread of high-level resistance to multiple antimalarial drugs by Plasmodium falciparum has brought about an urgent need for new treatments that will be active against multidrug resistant malaria infections. One such treatment, ELQ-331 (MMV-167), an alkoxy carbonate prodrug of 4(1H)-quinolone ELQ-300, is currently in preclinical development with the Medicines for Malaria Venture. Clinical development of ELQ-331 or similar compounds will require the availability of isotopically labeled analogs. Unfortunately, a suitable method for the deuteration of these important compounds was not found in the literature. Here, we describe a facile and scalable method for the deuteration of 4(1H)-quinolone ELQ-300, its alkoxycarbonate prodrug ELQ-331, and their respective N-oxides using deuterated acetic acid.


Subject(s)
Chemistry Techniques, Synthetic , Deuterium , Quinolones , Quinolones/chemical synthesis , Quinolones/chemistry , Deuterium/chemistry , Prodrugs/chemical synthesis , Prodrugs/chemistry , Prodrugs/pharmacology , Antimalarials/chemical synthesis , Antimalarials/chemistry , Antimalarials/pharmacology
7.
Int J Biol Macromol ; 268(Pt 2): 131724, 2024 May.
Article in English | MEDLINE | ID: mdl-38653427

ABSTRACT

The emergence of novel well-defined biological macromolecular architectures containing fluorine moieties displaying superior functionalities can satisfactorily address many biomedical challenges. In this research, ABA- and AB-type glucose-based biological macromolecules were synthesized using acryl-2,3,4,6-tetra-O-acetyl-D-glucopyranoside with pentafluorophenyl (FPM), pentafluorobenzyl (FBM), phenyl (PM) and benzyl (BM) methacrylate-based macro-RAFT agents following RAFT polymerization. The macro-RAFT agents and the corresponding copolymers were characterized by 19F, 1H, and 13C NMR and FTIR spectroscopic techniques to understand the chemical structure, molecular weight by size-exclusion chromatography, thermal analysis by TGA and DSC. Thermal stability (Td5%) of the FPM and FBM fluoro-based polymers was observed in the range of 219-267 °C, while the non-fluoro PM and BM polymers exhibited in the range of 216-264 °C. Among the macro-RAFT agents, PFPM (107 °C, ΔH: 0.613 J/g) and PPM (103 °C, ΔH: 0.455 J/g) showed higher Tm values, while among the block copolymers, PFBM-b-PG (123 °C, ΔH: 0.412 J/g) and PG-b-PFPM-b-PG (126 °C, ΔH: 0.525 J/g) exhibited higher Tm values. PFBMT and PPM macro-RAFT agents, PPM-b-PG and PG-b-PPM-b-PG copolymer spin-coated films showed the highest hydrophobicity (120°) among the synthesized polymers. The block copolymers exhibited self-assembled segregation by using relatively hydrophobic segments as the core and hydrophilic moieties as the corona. Synthesized biological macromolecules exhibit maximum antibacterial activity towards S. aureus than E. coli bacteria. Fluorophenyl (PFPM) and non-fluorobenzyl-based (PBMT) macro-RAFT agents exhibit low IC50 values, suggesting high cytotoxicity. All the triblock copolymers exhibit lesser cytotoxicity than the di-block polymers.


Subject(s)
Glucose , Macromolecular Substances , Glucose/chemistry , Macromolecular Substances/chemistry , Macromolecular Substances/chemical synthesis , Macromolecular Substances/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Polymers/chemistry , Polymers/chemical synthesis , Polymers/pharmacology , Humans , Polymerization , Molecular Weight , Fluorine/chemistry , Chemistry Techniques, Synthetic
8.
Int J Biol Macromol ; 267(Pt 1): 131407, 2024 May.
Article in English | MEDLINE | ID: mdl-38582463

ABSTRACT

Succinate dehydrogenase (SDH) is an important inner mitochondrial membrane-bound enzyme involved in redox reactions during the tricarboxylic acid cycle. Therefore, a series of novel chitosan derivatives were designed and synthesized as potential microbicides targeting SDH and precisely characterized by FTIR, 1H NMR and SEM. Their antifungal and antibacterial activities were evaluated against Botrytis cinerea, Fusarium graminearum, Staphylococcus aureus and Escherichia coli. The bioassays revealed that these chitosan derivatives exerted significant antifungal effects, with four of the compounds achieving 100 % inhibition of Fusarium graminearum merely at a concentration of 0.5 mg/mL. Additionally, CSGDCH showed 79.34 % inhibition of Botrytis cinerea at a concentration of 0.1 mg/mL. In vitro antibacterial tests revealed that CSGDCH and CSGDBH have excellent Staphylococcus aureus and Escherichia coli inhibition with MICs of 0.0156 mg/mL and 0.03125 mg/mL, respectively. Molecular docking studies have been carried out to explore the binding energy and binding mode of chitosan and chitosan derivatives with SDH. The analyses indicated that chitosan derivatives targeted the active site of the SDH protein more precisely, disrupting its normal function and ultimately repressing the growth of microbial cells. Furthermore, the chitosan derivatives were also evaluated biologically for antioxidation, and all of these compounds had a greater degree of reducing power, superoxide radical, hydroxyl radical and DPPH-radical scavenging activity than chitosan. This research has the potential for the development of agricultural antimicrobial agents.


Subject(s)
Antioxidants , Chitosan , Enzyme Inhibitors , Molecular Docking Simulation , Schiff Bases , Succinate Dehydrogenase , Chitosan/chemistry , Chitosan/pharmacology , Succinate Dehydrogenase/antagonists & inhibitors , Succinate Dehydrogenase/metabolism , Succinate Dehydrogenase/chemistry , Schiff Bases/chemistry , Schiff Bases/pharmacology , Schiff Bases/chemical synthesis , Antioxidants/pharmacology , Antioxidants/chemistry , Antioxidants/chemical synthesis , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Glycine/chemistry , Glycine/analogs & derivatives , Glycine/pharmacology , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/chemical synthesis , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Escherichia coli/drug effects , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/chemical synthesis , Fusarium/drug effects , Botrytis/drug effects , Chemistry Techniques, Synthetic
9.
Int J Biol Macromol ; 267(Pt 2): 131591, 2024 May.
Article in English | MEDLINE | ID: mdl-38621574

ABSTRACT

In the present study, a novel environment friendly dry method for preparation of guar gum maleate (GGM) with varying degrees of substitution (DS; 0.02-1.04) was optimized. GGM with a maximum DS of 1.04 was successfully synthesized using guar gum (GG) and maleic anhydride (MA) in proportion of 1: 1 at 80 °C with 4 h of reaction time. The activation energy for the reaction was determined to be 36.91 ± 3.61 kJ mol-1 with pre-exponential factor of 1392 min-1. Esterification of GG was confirmed by FT-IR and 13C NMR. Analysis using size exclusion chromatography (SEC) indicated a decrease in weight average molecular weight (Mw) of the polymer with an increase in polydispersity index (PDI) due to esterification. In comparison with GG, GGM displayed increased hydrophobicity and reduced thermal stability, as analysed by differential scanning calorimetry (DSC). Rheological studies of GGM revealed that initial apparent viscosity decreased with increasing DS. For the first time, the study offered valuable insights on GGM synthesis under dry solvent-less reaction conditions enabling simpler and scalable synthesis process.


Subject(s)
Galactans , Maleates , Mannans , Plant Gums , Plant Gums/chemistry , Galactans/chemistry , Mannans/chemistry , Kinetics , Maleates/chemistry , Molecular Weight , Viscosity , Esterification , Rheology , Temperature , Chemistry Techniques, Synthetic , Hydrophobic and Hydrophilic Interactions
10.
J Labelled Comp Radiopharm ; 67(5): 180-185, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38605481

ABSTRACT

Velagliflozin is the active ingredient of the first oral liquid medication approved by the Food and Drug Administration for the treatment of diabetes in cats. This compound belongs to the known class of sodium-glucose cotransporter 2 inhibitors approved to treat diabetes in human. Here, we report the detailed synthesis of velagliflozin labeled with carbon 14 and carbon 13.


Subject(s)
Carbon Isotopes , Carbon Radioisotopes , Carbon Radioisotopes/chemistry , Carbon Isotopes/chemistry , Chemistry Techniques, Synthetic , Glucosides/chemical synthesis , Glucosides/chemistry , Glucosides/pharmacology , Sodium-Glucose Transporter 2 Inhibitors/chemical synthesis , Sodium-Glucose Transporter 2 Inhibitors/chemistry , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Benzhydryl Compounds
11.
J Am Chem Soc ; 146(12): 7876-7884, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38489244

ABSTRACT

Biocatalysis is becoming an indispensable tool in organic synthesis due to high enzymatic catalytic efficiency as well as exquisite chemo- and stereoselectivity. Some biocatalysts display great promiscuity including a broad substrate scope as well as the ability to catalyze more than one type of transformation. These promiscuous activities have been applied individually to efficiently access numerous valuable target molecules. However, systems in which enzymes possessing multiple different catalytic activities are applied in the synthesis are less well developed. Such multifunctional biocatalysts (MFBs) would simplify chemical synthesis by reducing the number of operational steps and enzyme count, as well as simplifying the sequence space that needs to be engineered to develop an efficient biocatalyst. In this Perspective, we highlight recently reported MFBs focusing on their synthetic utility and mechanism. We also offer insight into their origin as well as comment on potential strategies for their discovery and engineering.


Subject(s)
Biocatalysis , Catalysis , Chemistry Techniques, Synthetic
12.
Top Curr Chem (Cham) ; 382(1): 10, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38457062

ABSTRACT

Organophosphorus compounds have long been considered valuable in both organic synthesis and life science. P(III)-nucleophiles, such as phosphites, phosphonites, and diaryl/alkyl phosphines, are particularly noteworthy as phosphorylation reagents for their ability to form new P-C bonds, producing more stable, ecofriendly, and cost-effective organophosphorus compounds. These nucleophiles follow similar phosphorylation routes as in the functionalization of P-H bonds and P-OH bonds. Activation can occur through photocatalytic, electrocatalytic, or thermo-driven reactions, often in coordination with a Michaelis-Arbuzov-trpe rearrangement process, to produce the desired products. As such, this review offers a thorough overview of the phosphorylated transformation and potential mechanisms of P(III)-nucleophiles, specifically focusing on developments since 2010. Notably, this review may provide researchers with valuable insights into designing and synthesizing functionalized organophosphorus compounds from P(III)-nucleophiles, guiding future advancements in both research and practical applications.


Subject(s)
Organophosphorus Compounds , Phosphines , Organophosphorus Compounds/chemistry , Phosphines/chemistry , Chemistry Techniques, Synthetic
13.
ChemSusChem ; 17(8): e202400234, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38441462

ABSTRACT

As we work to transition the modern society that is based on non-renewable chemical feedstocks to a post-modern society built around renewable sources of energy, fuels, and chemicals, there is a need to identify the renewable resources and processes for converting them to platform chemicals. Herein, we explore a strategy for utilizing the p-hydroxybenzoate in biomass feedstocks (e. g., poplar and palm trees) and converting it into a portfolio of commodity chemicals. The targeted bio-derived product in the first processing stage is p-hydroxybenzamide produced from p-hydroxybenzoate esters found in the plant. In the second stage a continuous reaction process converts the p-hydroxybenzamide to p-aminophenol via the Hofmann rearrangement and recovers the unreacted p-hydroxybenzamide. In the third stage the p-aminophenol can be acetylated to form paracetamol, which is readily isolated by liquid/liquid extraction at >95 % purity and an overall p-hydroxybenzamide-to-paracetamol process yield of ~90 %. We explore how utilization of protecting groups alters the challenges in this process and expands the portfolio of possible products to include p-(methoxymethoxy)aniline and N-acetyl-p-(methoxymethoxy)aniline. These target compounds could become value-added renewably-sourced platform chemicals that could be used to produce biodegradable plastics, pigments, and pharmaceuticals.


Subject(s)
Acetaminophen , Aminophenols , Biomass , Aminophenols/chemistry , Acetaminophen/chemistry , Acetaminophen/chemical synthesis , Benzamides/chemistry , Benzamides/chemical synthesis , Chemistry Techniques, Synthetic , Parabens/chemistry
14.
Nature ; 628(8007): 326-332, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38480891

ABSTRACT

Heteroarenes are ubiquitous motifs in bioactive molecules, conferring favourable physical properties when compared to their arene counterparts1-3. In particular, semisaturated heteroarenes possess attractive solubility properties and a higher fraction of sp3 carbons, which can improve binding affinity and specificity. However, these desirable structures remain rare owing to limitations in current synthetic methods4-6. Indeed, semisaturated heterocycles are laboriously prepared by means of non-modular fit-for-purpose syntheses, which decrease throughput, limit chemical diversity and preclude their inclusion in many hit-to-lead campaigns7-10. Herein, we describe a more intuitive and modular couple-close approach to build semisaturated ring systems from dual radical precursors. This platform merges metallaphotoredox C(sp2)-C(sp3) cross-coupling with intramolecular Minisci-type radical cyclization to fuse abundant heteroaryl halides with simple bifunctional feedstocks, which serve as the diradical synthons, to rapidly assemble a variety of spirocyclic, bridged and substituted saturated ring types that would be extremely difficult to make by conventional methods. The broad availability of the requisite feedstock materials allows sampling of regions of underexplored chemical space. Reagent-controlled radical generation leads to a highly regioselective and stereospecific annulation that can be used for the late-stage functionalization of pharmaceutical scaffolds, replacing lengthy de novo syntheses.


Subject(s)
Carbon , Chemistry Techniques, Synthetic , Heterocyclic Compounds, 1-Ring , Pharmaceutical Preparations , Carbon/chemistry , Cyclization , Heterocyclic Compounds, 1-Ring/chemical synthesis , Heterocyclic Compounds, 1-Ring/chemistry , Solubility , Oxidation-Reduction , Photochemistry , Pharmaceutical Preparations/chemical synthesis , Pharmaceutical Preparations/chemistry , Chemistry Techniques, Synthetic/methods
15.
J Org Chem ; 89(7): 4261-4282, 2024 04 05.
Article in English | MEDLINE | ID: mdl-38508870

ABSTRACT

Small molecule therapeutics represent the majority of the FDA-approved drugs. Yet, many attractive targets are poorly tractable by small molecules, generating a need for new therapeutic modalities. Due to their biocompatibility profile and structural versatility, peptide-based therapeutics are a possible solution. Additionally, in the past two decades, advances in peptide design, delivery, formulation, and devices have occurred, making therapeutic peptides an attractive modality. However, peptide manufacturing is often limited to solid-phase peptide synthesis (SPPS), liquid phase peptide synthesis (LPPS), and to a lesser extent hybrid SPPS/LPPS, with SPPS emerging as a predominant platform technology for peptide synthesis. SPPS involves the use of excess solvents and reagents which negatively impact the environment, thus highlighting the need for newer technologies to reduce the environmental footprint. Herein, fourteen American Chemical Society Green Chemistry Institute Pharmaceutical Roundtable (ACS GCIPR) member companies with peptide-based therapeutics in their portfolio have compiled Process Mass Intensity (PMI) metrics to help inform the sustainability efforts in peptide synthesis. This includes PMI assessment on 40 synthetic peptide processes at various development stages in pharma, classified according to the development phase. This is the most comprehensive assessment of synthetic peptide environmental metrics to date. The synthetic peptide manufacturing process was divided into stages (synthesis, purification, isolation) to determine their respective PMI. On average, solid-phase peptide synthesis (SPPS) (PMI ≈ 13,000) does not compare favorably with other modalities such as small molecules (PMI median 168-308) and biopharmaceuticals (PMI ≈ 8300). Thus, the high PMI for peptide synthesis warrants more environmentally friendly processes in peptide manufacturing.


Subject(s)
Peptides , Solid-Phase Synthesis Techniques , Peptides/chemistry , Chemistry Techniques, Synthetic , Solvents
16.
Int J Biol Macromol ; 266(Pt 1): 131211, 2024 May.
Article in English | MEDLINE | ID: mdl-38552688

ABSTRACT

Our study aimed at developing polymer micelles that possess redox sensitivity and excellent controlled release properties. 3,3'-dithiodipropionic acid (DTDPA, Abbreviation in synthetic polymers: SS) was introduced as ROS (Reactive oxygen species)response bond and connecting arm to couple hydroxyethyl starch (HES) with oleanolic acid (OA), resulting in the synthesis of four distinct grafting ratios of HES-SS-OA. FTIR (Fourier Transform infrared spectroscopy) and 1H NMR (1H Nuclear magnetic resonance spectra) were used to verify the triumphant combination of HES-SS-OA. Polymer micelles were found to encapsulate OA in an amorphous form, as indicated by the results of XRD (X-ray diffraction) and DSC (Differential scanning calorimetry). When the OA grafting rate on HES increased from 7.72 % to 11.75 %, the particle size decreased from 297.79 nm to 201.39 nm as the polymer micelles became compact due to enhanced hydrophobicity. In addition, the zeta potential changed from -16.42 mv to -25.78 mv, the PDI (polydispersity index) decreased from 0.3649 to 0.2435, and the critical micelle concentration (CMC) decreased from 0.0955 mg/mL to 0.0123 mg/mL. Results of erythrocyte hemolysis, cytotoxicity and cellular uptake illustrated that HES-SS-OA had excellent biocompatibility and minimal cytotoxicity for AML-12 cells. Disulfide bond breakage of HES-SS-OA in the presence of H2O2 and GSH confirmed the redox sensitivity of the HES-SS-OA micelles and their excellent controlled release properties for OA. These findings suggest that HES-SS-OA can be potentially used in the future as a healthcare drug and medicine for the prevention or adjuvant treatment of inflammation.


Subject(s)
Hydroxyethyl Starch Derivatives , Micelles , Oleanolic Acid , Oxidation-Reduction , Hydroxyethyl Starch Derivatives/chemistry , Oleanolic Acid/chemistry , Polymers/chemistry , Drug Liberation , Drug Carriers/chemistry , Humans , Hemolysis/drug effects , Chemistry Techniques, Synthetic , Animals , Particle Size
17.
J Am Chem Soc ; 146(6): 4270-4280, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38316681

ABSTRACT

Peptide therapeutics have experienced a rapid resurgence over the past three decades. While a few peptide drugs are biologically produced, most are manufactured via chemical synthesis. The cycle of prior protection of the amino group of an α-amino acid, activation of its carboxyl group, aminolysis with the free amino group of a growing peptide chain, and deprotection of the N-terminus constitutes the principle of conventional C → N peptide chemical synthesis. The mandatory use of the Nα-protecting group invokes two additional operations for incorporating each amino acid, resulting in poor step- and atom-economy. The burgeoning demand in the peptide therapeutic market necessitates cost-effective and environmentally friendly peptide manufacturing strategies. Inverse peptide chemical synthesis using unprotected amino acids has been proposed as an ideal and appealing strategy. However, it has remained unsuccessful for over 60 years due to severe racemization/epimerization during N → C peptide chain elongation. Herein, this challenge has been successfully addressed by ynamide coupling reagent employing a transient protection strategy. The activation, transient protection, aminolysis, and in situ deprotection were performed in one pot, thus offering a practical peptide chemical synthesis strategy formally using unprotected amino acids as the starting material. Its robustness was exemplified by syntheses of peptide active pharmaceutical ingredients. It is also amenable to fragment condensation and inverse solid-phase peptide synthesis. The compatibility to green solvents further enhances its application potential in large-scale peptide production. This study offered a cost-effective, operational convenient, and environmentally benign approach to peptides.


Subject(s)
Amino Acids , Peptides , Amino Acids/chemistry , Peptides/chemistry , Chemistry Techniques, Synthetic , C-Peptide , Peptide Biosynthesis , Solid-Phase Synthesis Techniques
18.
Methods Mol Biol ; 2763: 187-199, 2024.
Article in English | MEDLINE | ID: mdl-38347411

ABSTRACT

Mucins are sugar-rich glycoproteins. Glycoprotein sugar moieties are structurally diverse, making it difficult to obtain naturally pure glycoproteins. Chemical synthesis is a powerful tool for obtaining target or designed compounds. Automated peptide synthesizers are commercially available, and many use the solid-phase peptide synthesis (SPPS) method. In addition, some of these synthesizers apply microwave irradiation to obtain higher reaction yields, thereby enabling the synthesis of 40 to 50 amino acid residual glycopeptides. Theoretically, glycopeptides can be synthesized using methods similar to those used for peptide synthesis, but glycosylated amino acid synthons are less stable than amino acid synthons and are also very expensive. Therefore, they are not suitable for use in large excess amounts. Many of oligosaccharide-linked amino acid synthons are not commercially available, so they must be specially prepared, and they also require careful handling that demands specific organic synthesis experience and techniques. However, monosaccharide-linked amino acid synthons are commercially available and are relatively easy to handle. Here, as an entry into glycopeptide synthesis, we describe a typical glycopeptide synthesis procedure for a 27 amino acid residual MUC1 repeating unit with monosaccharides.


Subject(s)
Glycopeptides , Mucins , Mucins/chemistry , Glycopeptides/chemistry , Mucin-1 , Carbohydrates/chemistry , Glycoproteins , Chemistry Techniques, Synthetic , Sugars , Amino Acids/chemistry
19.
Angew Chem Int Ed Engl ; 63(14): e202318897, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38326236

ABSTRACT

Mirror-image proteins (D-proteins) are useful in biomedical research for purposes such as mirror-image screening for D-peptide drug discovery, but the chemical synthesis of many D-proteins is often low yielding due to the poor solubility or aggregation of their constituent peptide segments. Here, we report a Lys-C protease-cleavable solubilizing tag and its use to synthesize difficult-to-obtain D-proteins. Our tag is easily installed onto multiple amino acids such as DLys, DSer, DThr, and/or the N-terminal amino acid of hydrophobic D-peptides, is impervious to various reaction conditions, such as peptide synthesis, ligation, desulfurization, and transition metal-mediated deprotection, and yet can be completely removed by Lys-C protease under denaturing conditions to give the desired D-protein. The efficacy and practicality of the new method were exemplified in the synthesis of two challenging D-proteins: D-enantiomers of programmed cell death protein 1 IgV domain and SARS-CoV-2 envelope protein, in high yield. This work demonstrates that the enzymatic cleavage of solubilizing tags under denaturing conditions is feasible, thus paving the way for the production of more D-proteins.


Subject(s)
Peptides , Proteins , Proteins/chemistry , Peptides/chemistry , Amino Acids/chemistry , Chemistry Techniques, Synthetic/methods , Peptide Hydrolases , Endopeptidases
20.
Eur J Nucl Med Mol Imaging ; 51(7): 2023-2035, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38376806

ABSTRACT

Integrin receptor αvß3 and gastrin-releasing peptide receptor (GRPR) expression of tumors could be detected using PET imaging with radiolabeled Arg-Gly-Asp (RGD) and the antagonistic bombesin analog RM26, respectively. The purpose of this study was to investigate the dual receptor-targeting property of the heterodimer RGD-RM26-03 (denoted as LNC1015), demonstrate the tumor diagnostic value of [68Ga]Ga-LNC1015 in preclinical experiments, and evaluate its preliminary clinical feasibility. METHODS: LNC1015 was designed and synthesized by linking cyclic RGD and the RM26 peptide. Preclinical pharmacokinetics were detected in a PC3 xenograft model using microPET and biodistribution studies. The clinical feasibility of [68Ga]Ga-LNC1015 PET/CT was performed in patients with breast cancer, and the results were compared with those of 18F-fluorodeoxyglucose (FDG). RESULTS: [68Ga]Ga-LNC1015 had good stability in saline for at least 2 h, and favorable binding affinity and specificity were demonstrated in vitro and in vivo. The tumor uptake and retention of [68Ga]Ga-LNC1015 during PET imaging were improved compared with its monomeric counterparts [68Ga]Ga-RGD and [68Ga]Ga-RM26 at all the time points examined. In our initial clinical studies, the tumor uptake and tumor-to-background ratio (TBR) of primary and metastatic lesions in [68Ga]Ga-LNC1015 PET/CT were significantly higher than those in [18F]FDG PET/CT, resulting in high lesion detection rate and tumor delineation. CONCLUSION: The dual targeting radiotracer [68Ga]Ga-LNC1015 showed significantly improved tumor uptake and retention, as well as lower liver uptake than [68Ga]Ga-RGD and [68Ga]Ga-RM26 monomer. The first-in-human study showed high TBRs in patients, suggesting favorable pharmacokinetics and high clinical feasibility for PET/CT imaging of cancer.


Subject(s)
Gallium Radioisotopes , Integrin alphaVbeta3 , Oligopeptides , Receptors, Bombesin , Receptors, Bombesin/metabolism , Humans , Animals , Mice , Female , Integrin alphaVbeta3/metabolism , Oligopeptides/pharmacokinetics , Oligopeptides/chemistry , Tissue Distribution , Male , Positron Emission Tomography Computed Tomography/methods , Radiochemistry , Middle Aged , Cell Line, Tumor , Radioactive Tracers , Radiopharmaceuticals/pharmacokinetics , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/chemistry , Chemistry Techniques, Synthetic , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/metabolism
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