Abstract Proteolysis-targeting chimeras (PROTACs) are driving medicinal chemistry progress, yet efficient synthesis and rational linker design remain two critical bottlenecks for their clinical translation. Those core challenges directly limit the advancement of PROTACs from preclinical research to practical application. This review focuses on state-of-the-art enabling chemical strategies to address these key bottlenecks, ensuring tight relevance to PROTACs development needs. The modular assembly can be streamlined by click chemistry, multicomponent, and late-stage C–H functionalizations, whereas microscale and solid-phase platforms can be used to deliver thousands of analogues in days without purification. In this work, we emphasize covalent sulfonyl fluoride warheads and photocaged or photoswitchable scaffolds that provide spatiotemporal control of degradation. The employment of dynamic combinatorial chemistry, DNA-encoded libraries, and intracellular self-assembly further expands chemical space and accelerates hit triage. At last, we outline how artificial intelligence-driven modeling integrates these data to predict linker length, exit vector geometry, and ADME profiles, shortening iterative design cycles. Collectively, these chemistry-centric innovations are turning PROTACs from a conceptual breakthrough into a practical drug-discovery engine by directly addressing the synthesis, optimization, and functional control challenges that have impeded their clinical advancement.

This paper aims to improve the synthetic process of molnupiravir based on previously reported synthetic routes. The route begins with uracil (ML-2), which is protected with an isopropyl group to yield ML-3 (Step 1), followed by an esterification and a triazolation reaction (Steps 2 and 3) to produce ML-5, which, via a hydroxylation reaction and deprotection (Steps 4 and 5), gives the target product ML-1. Nuclear magnetic resonance (1H NMR) and mass spectra were used for chemical structure identification. There are mainly the following improvements, including: (1) replacing the separate addition of acetone and concentrated H2SO4 with 2,2-dimethoxypropane and catalytic p-toluenesulfonic acid monohydrate in Step 1, simplifying the workup operation and reducing the dosage of reaction solvent. (2) Optimize the synthesis conditions of ML-5, reduce the formation of impurities, and improve the purity of the crude product from 43.12 to 85.21%. (3) Three impurities were isolated, two of which are new compounds. This article lays a foundation to obtain molnupiravir with controllable quality and a stable process for the treatment of coronavirus disease 2019.

Targeting cyclin-dependent kinase (CDK) families is a promising strategy for cancer therapy due to the close association between CDKs and an abnormal cell cycle or transcriptional regulation. However, after extensive clinical use, small molecule inhibitors of CDKs have also exposed issues, such as off-target effects or acquired drug resistance. Targeting protein degradation technology, which has been validated to be effective for many targets, has undergone more than 20 years of development, and some of these methods have been pushed into clinical trials. In this review, we summarized some successful reports on CDK-targeted degradation during recent years. Moreover, some challenging issues and future development trends are highlighted in the prospect section, which might provide updated insight into the development of novel CDK-targeted degraders with great potential as a new weapon for cancer therapy.

Abstract While some Coleus species have demonstrated anti-HIV activity, the potential of Mayana (Coleus scutellarioides Benth.) remains largely unexplored. This study therefore aimed to investigate the anti-HIV potential of phytoconstituents from Mayana using in silico methods. Phytochemicals from Mayana were identified using gas chromatography–mass spectrometry and their binding affinity against HIV-1 integrase (IN), protease (PR), and reverse transcriptase (RT) were evaluated through molecular docking simulations. In this work, a total of 32 individual compounds were identified. Stigmasterol was found to have the highest binding affinity to HIV IN (−8.571 kcal/mol) and HIV PR (−10.250 kcal/mol), whereas caryophyllene showed the highest affinity to HIV RT (−9.625 kcal/mol). These compounds also demonstrated multitarget interactions, suggesting potential inhibitory effects. However, compared with synthetic drugs such as amprenavir (−9.421 kcal/mol for PR), raltegravir (−9.825 kcal/mol for IN), and nevirapine (−9.748 kcal/mol for RT), the phytoconstituents had lower binding affinities. Pharmacokinetic predictions revealed that the top-ranked phytochemicals conform to Lipinski's Rule of Five, indicating favorable drug-like properties. Overall, Mayana contains bioactive phytoconstituents with promising affinity for key HIV-1 enzymes, supporting the potential of Mayana as a source of novel anti-HIV leads. However, further in vitro and in vivo studies are needed to confirm the efficacy, safety, and pharmacokinetic profile.

Pravastatin sodium (PS) is a hydrophilic statin lipid-lowering drug that reduces low-density lipoprotein levels in the blood by inhibiting the activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase. It is known to exist in 17 crystalline forms, with some different crystalline forms overlapping in the powder diffraction patterns, making it difficult to control the purity of the crystalline forms. In this study, we aimed to determine the purity of PS crystals using powder X-ray diffraction (PXRD), mid-infrared (MIR) spectroscopy, and Raman techniques. The predictive ability of the partial least squares (PLS) model was constructed and assessed using SPXY, K_S, and Random methods at different partitioning ratios. PLS calibration curves were established based on the relationship between PXRD, MIR, and Raman data and the content of a solid forms of PS (PS-A) in different ranges (full and partial spectra) using different preprocessing algorithms such as multiplicative scattering correction, standard normal variable, Savitzky–Golay filtering, and derivative spectroscopy, or a combination of them. The results showed that the calibration model (y = 0.999x + 0.008 with R 2 = 0.999) established using the PXRD method was better, with a low detection limit (1.52%) and quantification limit (4.60%). In addition, by analyzing the testing results of the blind sample, it was found that the confidence intervals of the predicted values of MIR and Raman were wider, indicating a large uncertainty of their parameter estimation. Therefore, it will be better to select the calibration model established by the PXRD method to determine the purity of PS in actual production. This can provide more reliable methodological support for the quality control of pharmaceutical products.

(2-Bromo-5-chloro-4-((5-ethylthiophen-2-yl)methyl)phenyl)methanol (1) is a key intermediate of the SGLT2 inhibitor LH-1801. This study aimed to explore an efficient process for the synthesis of 1 on a large scale. In this work, the synthetic route started with 3-amino-4-methylbenzoic acid methyl ester (2), followed by (1) bromination, (2) diazotization–Sandmeyer reaction, (3) the oxidation of the benzylic hydrogen to give the corresponding benzoic acid, (4) Friedel–Crafts acylation, and (5) reduction of a carbonyl group (C = O) into a methylene group (–CH2–) to achieve the target product. We optimized the diazotization-Sandmeyer reaction conditions and reaction parameters for a successful oxidation sequence. In addition, a reduction system for Step 5 was screened. With the optimal reduction system (NaBH4/BF3•THF) in hand, the target product (1) could be generated in an efficient and concise one-step reduction approach. Given the above, the synthesis route with process optimization delivered the target product (1) in only five steps with an overall yield of 18.9% and a purity higher than 99%.

Abstract Vosoritide is a therapeutic peptide that promotes skeletal growth by targeting the NPR-B receptor and was approved in 2021 for the treatment of achondroplasia. However, its high production cost poses a considerable economic burden on patients, limiting its widespread use. This study aims to establish an efficient and cost-effective biosynthetic process for the production of Vosoritide using Escherichia coli. In this work, Vosoritide was expressed as inclusion bodies (IBs) in E. coli BL21 (DE3) via a gp55 fusion strategy. Downstream processes, including fermentation, HCl-induced acidic cleavage of IBs, pH-dependent protein precipitation, as well as the performing conditions of the ion-exchange chromatography and reverse-phase chromatography, were optimized. The analysis methods included sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), high-performance liquid chromatography (HPLC), and liquid chromatography-tandem mass spectrometry. Cyclic guanosine monophosphate (cGMP) assays were conducted to assess the biological activity of the protein in NIH3T3 cells. Vosoritide was obtained at 1.3 g per liter of fermentation broth with a purity exceeding 99%. The peptide's primary structure, molecular weight, and disulfide bond integrity were also confirmed through mass spectrometry and peptide mapping. The purified Vosoritide stimulated cGMP production in NIH3T3 cells with a half-maximal effective concentration (EC50) of 0.37 nmol/L. In conclusion, this study provided a scalable, high-yield production method for Vosoritide that yields Vosoritide with pharmaceutical-grade purity and activity, holding significant potential for manufacturing a cost-effective biosimilar with broader clinical accessibility.

Abstract Tavapadon is a potent, selective G protein-biased partial agonist for the dopamine D1/D5 receptors, with positive experimental results in phase 3 trials for the treatment of Parkinson's disease (PD). This study aims to study the structure–activity relationship (SAR) of tavapadon to discover novel compounds with improved binding activity to D1/D5 receptors. In this work, a series of tavapadon derivatives were designed and synthesized based on the pharmacophores of tavapadon. Their binding activity to D1/D5 receptors was evaluated by determining in vitro median effect concentration (EC50). The binding mode was predicted by molecular docking. Our data showed that among those compounds, III-1 exhibited a similar binding pose to tavapadon at D1 dopamine receptors and demonstrated nanomolar potency for both D1 and D5 receptors. Compound III-1 is a potent partial agonist for the D1/D5 receptors, and may be a potent alternative to tavapadon for the treatment of PD in further study.

Abstract Brolucizumab was the first single-chain fragment variable (scFv) antibody approved by the FDA for the treatment of age-related macular degeneration (AMD). However, the manufacturing process of brolucizumab remains rarely reported. This study aimed to explore a bioprocess for the production of brolucizumab, where it is expressed as inclusion bodies (IBs) in Escherichia coli (E. coli) BL21 (DE3) cells. In this work, IBs were initially obtained via high cell density fermentation (HCDF) at a high expression level of 30 g/L, followed by denaturation, refolding, and purification to obtain brolucizumab. The refolding parameters were systematically optimized to ensure a high yield of brolucizumab, with 413 mg of the target protein from a 1-L fermentation broth, and purity exceeding 98%. In addition, the amino acid sequence coverage and disulfide bond pairing of the protein were further verified. The results confirmed that brolucizumab has excellent structural integrity, high purity, and notable biological activity. The biosynthetic process holds significant potential for therapeutic applications of brolucizumab and provides valuable insights for the further development of additional scFv bioprocesses.