Synthetic approaches and clinical application of representative small-molecule inhibitors of phosphodiesterase.

Phosphodiesterases (PDEs) constitute a family of enzymes that play a pivotal role in the regulation of intracellular levels of cyclic nucleotides, including cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Dysregulation of PDE activity has been implicated in diverse pathological conditions encompassing cardiovascular disorders, pulmonary diseases, and neurological disorders. Small-molecule inhibitors targeting PDEs have emerged as promising therapeutic agents for the treatment of these ailments, some of which have been approved for their clinical use. Despite their success, challenges such as resistance mechanisms and off-target effects persist, urging continuous research for the development of next-generation PDE inhibitors. The objective of this review is to provide an overview of the synthesis and clinical application of representative approved small-molecule PDE inhibitors, with the aim of offering guidance for further advancements in the development of novel PDE inhibitors.

Retraction: Recent advances in total synthesis of protoberberine and chiral tetrahydroberberine alkaloids.

Retraction of 'Recent advances in total synthesis of protoberberine and chiral tetrahydroberberine alkaloids' by Zhen-Xi Niu et al., Nat. Prod. Rep., 2024, https://doi.org/10.1039/d4np00016a.

Synthetic routes and clinical application of Small-Molecule HER2 inhibitors for cancer therapy.

This comprehensive review undertakes a meticulous scrutiny of the synthesis and clinical applications pertaining to small-molecule tyrosine kinase inhibitors (TKIs) directed towards the human epidermal growth factor receptor 2 (HER2), a pivotal protagonist in the pathogenesis of cancer. Focused on compounds like lapatinib, neratinib, and tucatinib, the review delves into the intricate synthesis strategies, emphasizing the challenges associated with their structural complexity. The clinical utilization of HER2 TKIs underscores noteworthy strides in the therapeutic landscape for HER2-positive breast and gastric malignancies. Lapatinib, a dual HER2/ epidermal growth factor receptor (EGFR) inhibitor, has demonstrated efficacy in combination therapies, addressing the need for overcoming resistance mechanisms. Neratinib, an irreversible HER2 inhibitor, presents a promising avenue for patients with refractory tumors. Tucatinib, strategically engineered to traverse the blood-brain barrier, epitomizes a groundbreaking advancement in the management of metastatic HER2-positive breast cancer manifesting cerebral involvement. Despite their success, challenges such as resistance mechanisms and off-target effects persist, urging continuous research for the development of next-generation HER2 TKIs. This comprehensive review serves as a valuable resource for pharmaceutical scientists, offering insights into the synthetic intricacies and clinical impact of small-molecule TKIs targeting HER2.

Synthetic approaches and application of representative clinically approved fluorine-enriched anti-cancer medications.

Fluorine possesses distinctive chemical characteristics, such as its strong electron-withdrawing ability and small atomic size, which render it an invaluable asset in the design and optimization of pharmaceuticals. The utilization of fluorine-enriched medications for combating cancer has emerged as a prominent approach in medicinal chemistry and drug discovery, offering improved clinical outcomes and enhanced pharmacological properties. This comprehensive review explores the synthetic approaches and clinical applications of approved 22 representative fluorinated anti-cancer drugs from 2019 to present, shedding light on their historical development, brand names, drug target activity, mechanism of action, preclinical pharmacodynamics, clinical efficacy, and toxicity. Additionally, the review provides an extensive analysis of the representative synthetic techniques employed. Overall, this review emphasizes the significance of incorporating fluorine chemistry into anti-cancer drug research while highlighting promising future prospects for exploring compounds enriched with fluorine in the battle against cancer.

Synthetic Approaches and Clinical Application of Representative Small-Molecule Inhibitors of Cyclin-Dependent Kinase for Cancer Therapy.

The regulation of the cancer cell cycle heavily relies on cyclin-dependent kinases (CDKs). Targeting CDKs has been identified as a promising approach for effective cancer therapy. In recent years, there has been significant attention paid towards developing small-molecule CDK inhibitors in the field of drug discovery. Notably, five such inhibitors have already received regulatory approval for the treatment of different cancers, including breast tumors, lung malignancies, and hematological malignancies. This review provides an overview of the synthetic routes used to produce 17 representative small-molecule CDK inhibitors that have obtained regulatory approval or are currently being evaluated through clinical trials. It also discusses their clinical applications for treating CDK-related diseases and explores the challenges and limitations associated with their use in a clinical setting, which will stimulate the further development of novel CDK inhibitors. By integrating therapeutic applications, synthetic methodologies, and mechanisms of action observed in various clinical trials involving these CDK inhibitors, this review facilitates a comprehensive understanding of the versatile roles and therapeutic potential offered by interventions targeting CDKs.

Recent advances in total synthesis of protoberberine and chiral tetrahydroberberine alkaloids.

Covering: Up to 2024Due to the widespread distribution of protoberberine alkaloids (PBs) and tetrahydroberberine alkaloids (THPBs) in nature, coupled with their myriad unique physiological activities, they have garnered considerable attention from medical practitioners. Over the past few decades, synthetic chemists have devised various total synthesis methods to attain these structures, continually expanding reaction pathways to achieve more efficient synthetic strategies. Simultaneously, the chiral construction of THPBs has become a focal point. In this comprehensive review, we categorically summarized the developmental trajectory of the total synthesis of these alkaloids based on the core closure strategies of protoberberine and tetrahydroberberine.

Synthetic Routes and Clinical Application of Representative Small-Molecule EGFR Inhibitors for Cancer Therapy.

The epidermal growth factor receptor (EGFR) plays a pivotal role in cancer therapeutics, with small-molecule EGFR inhibitors emerging as significant agents in combating this disease. This review explores the synthesis and clinical utilization of EGFR inhibitors, starting with the indispensable role of EGFR in oncogenesis and emphasizing the intricate molecular aspects of the EGFR-signaling pathway. It subsequently provides information on the structural characteristics of representative small-molecule EGFR inhibitors in the clinic. The synthetic methods and associated challenges pertaining to these compounds are thoroughly examined, along with innovative strategies to overcome these obstacles. Furthermore, the review discusses the clinical applications of FDA-approved EGFR inhibitors such as erlotinib, gefitinib, afatinib, and osimertinib across various cancer types and their corresponding clinical outcomes. Additionally, it addresses the emergence of resistance mechanisms and potential counterstrategies. Taken together, this review aims to provide valuable insights for researchers, clinicians, and pharmaceutical scientists interested in comprehending the current landscape of small-molecule EGFR inhibitors.

Mitochondrial antioxidant elamipretide improves learning and memory impairment induced by chronic sleep deprivation in mice.

BACKGROUND: The inflammation and synaptic dysfunction induced by mitochondrial dysfunction play essential roles in the learning and memory impairment associated with sleep dysfunction. Elamipretide (SS-31), a novel mitochondrion-targeted antioxidant, was proven to improve mitochondrial dysfunction, the inflammatory response, synaptic dysfunction, and cognitive impairment in models of cerebral ischemia, sepsis, and type 2 diabetes. However, the potential for SS-31 to improve the cognitive impairment induced by chronic sleep deprivation (CSD) and its underlying mechanisms is unknown. METHODS: Adult c57BL/6J mice were subjected to CSD for 21 days using an activity wheel accompanied by daily intraperitoneal injection of SS-31 (5 mg/kg). The novel object recognition and Morris water maze test were used to evaluate hippocampus-dependent cognitive function. Western blotting and reverse transcription-quantitative polymerase chain reaction assays were used to determine the effects of CSD and SS-31 on markers of mitochondria, inflammation response, and synaptic function. Enzyme-linked immunosorbent assays were used to examine the levels of proinflammatory cytokines. RESULTS: SS-31 could improve the cognitive impairment induced by CSD. In particular, SS-31 treatment restored the CSD-induced decrease in sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor γ coactivator alpha levels and the increase in levels nuclear factor kappa-B and inflammatory cytokines, including interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha. Furthermore, SS-31 significantly increased the levels of brain-derived neurotrophic factor, postsynaptic density protein-95, and synaptophysin in CSD mice. CONCLUSION: Taken together, these results suggest that SS-31 could improve CSD-induced mitochondrial biogenesis dysfunction, inflammatory response, synaptic dysfunction, and cognitive impairment by increasing SIRT1 expression levels.

Fluorine in the pharmaceutical industry: Synthetic approaches and application of clinically approved fluorine-enriched anti-infectious medications.

The strategic integration of fluorine atoms into anti-infectious agents has become a cornerstone in the field of medicinal chemistry, owing to the unique influence of fluorine on the chemical and biological properties of pharmaceuticals. This review examines the synthetic methodologies that enable the incorporation of fluorine into anti-infectious drugs, and the resultant clinical applications of these fluorine-enriched compounds. With a focus on clinically approved medications, the discussion extends to the molecular mechanisms. It further outlines the specific effects of fluorination, which contribute to the heightened efficacy of anti-infective therapies. By presenting a comprehensive analysis of current drugs and their developmental pathways, this review underscores the continuing evolution and significance of fluorine in advancing anti-infectious treatment options. The insights offered extend valuable guidance for future drug design and the development of next-generation anti-infectious agents.

Synthesis and clinical application of new drugs approved by FDA in 2023.

In 2023, the U.S. Food and Drug Administration (FDA) granted approval to a total of 55 new drugs, comprising 29 new chemical entities (NCEs) and 25 new biological entities (NBEs). These drugs primarily focus on oncology, the central nervous system, anti-infection, hematology, cardiovascular, ophthalmology, immunomodulatory and other therapeutic areas. Out of the 55 drugs, 33 (60 %) underwent an accelerated review process and received approval, while 25 (45 %) were specifically approved for the treatment of rare diseases. The purpose of this review is to provide an overview of the clinical uses and production techniques of 29 newly FDA-approved NCEs in 2023. Our intention is to offer a comprehensive understanding of the synthetic approaches employed in the creation of these drug molecules, with the aim of inspiring the development of novel, efficient, and applicable synthetic methodologies.

Harmonizing the craft of crafting clinically endorsed small-molecule BCR-ABL tyrosine kinase inhibitors for the treatment of hematological malignancies.

The advancement and practical use of small-molecule tyrosine kinase inhibitors (TKIs) that specifically target the BCR-ABL fusion protein have introduced a revolutionary era of precision medicine for the treatment of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). This review offers a comprehensive exploration of the synthesis, mechanisms of action, and clinical implementation of clinically validated TKIs in the context of BCR-ABL, emphasizing the remarkable strides made in achieving therapeutic precision. We delve into the intricate design and synthesis of these small molecules, highlighting the synthetic strategies and modifications that have led to increased selectivity, enhanced binding affinities, and reduced off-target effects. Additionally, we discuss the structural biology of BCR-ABL inhibition and how it informs drug design. The success of these compounds in inhibiting aberrant kinase activity is a testament to the meticulous refinement of the synthetic process. Furthermore, this review provides a detailed analysis of the clinical applications of these TKIs, covering not only their efficacy in achieving deep molecular responses but also their impact on patient outcomes, safety profiles, and resistance mechanisms. We explore ongoing research efforts to overcome resistance and enhance the therapeutic potential of these agents. In conclusion, the synthesis and utilization of clinically validated small-molecule TKIs targeting BCR-ABL exemplify the transformative power of precision medicine in the treatment of hematological malignancies. This review highlights the evolving landscape of BCR-ABL inhibition and underscores the continuous commitment to refining and expanding the therapeutic repertoire for these devastating diseases.

Letter to editor 'Non-invasive model for predicting high-risk esophageal varices based on liver and spleen stiffness'.

This letter to the editor relates to the study entitled "Non-invasive model for predicting high-risk esophageal varices based on liver and spleen stiffness". Acute bleeding caused by esophageal varices is a life-threatening complication in patients with liver cirrhosis. Due to the discomfort, contraindications, and associated complications of upper gastrointestinal endoscopy screening, it is crucial to identify an imaging-based non-invasive model for predicting high-risk esophageal varices in patients with cirrhosis.

Synthetic approaches and application of clinically approved small-molecule drugs to treat hepatitis.

Hepatitis, a global public health concern, presents a significant burden on healthcare systems worldwide. Particularly, hepatitis B and C are viral infections that can lead to severe liver damage, cirrhosis, and even hepatocellular carcinoma (HCC). The urgency to combat these diseases has driven researchers to explore existing small-molecule drugs as potential therapeutics. This comprehensive review provides a systematic overview of synthetic routes to key antiviral agents used to manage hepatitis. Furthermore, it elucidates the mechanisms of action of these drugs, shedding light on their interference with viral replication and liver disease progression. The review also discusses the clinical applications of these drugs, including their use in combination therapies and various patient populations. By evaluating the synthetic pathways and clinical utility of these drugs, this review not only consolidates current knowledge but also highlights potential future directions for research and drug development in the fight against hepatitis, ultimately contributing to improved patient outcomes and reduced global disease burden.

Deletion of the PPARδ gene exacerbates high-fat diet-induced nonalcoholic fatty liver disease in mice through the gut-liver axis.

Gut microbiota dysbiosis is an essential factor contributing to non-alcoholic fatty liver disease (NAFLD), in which the gut-liver axis plays a crucial role. Peroxisome proliferator-activated receptor δ (PPARδ) is considered a new direction for the research on NAFLD due to its positive regulation of glucose and lipid metabolism. Our experiment aimed to investigate the effect of PPARδ gene deletion on gut microbiota and NAFLD through the gut-liver axis. PPARδ-/- mice and wild-type mice were randomly divided into high-fat diet(HFD) groups and normal diet groups. In each group, six mice were sacrificed at weeks 4, 8, and 12. Metabolic indicators and inflammation indicators were measured, and the degree of liver steatosis and the ileum mucosa integrity were evaluated. Additionally, fecal samples were subjected to 16S rDNA gene sequencing and analysis of gut microbiota. Deletion of the PPARδ gene exhibited exacerbated effects on HFD-induced NAFLD and displayed more severe liver inflammation and intestinal mucosal barrier injuries. The HFD reduced the abundance of short-chain fatty acid (SCFA)-producing bacteria and increased the abundance of intestinal endotoxin-rich bacteria in mice. Deletion of the PPARδ gene exacerbated this trend, resulting in decreased abundances of norank_f__Eubacterium_coprostanoligenes_group and Alloprevotella and increased abundances of Acidibacter, unclassified_f__Comamonadaceae, unclassified_c__Alphaproteobacteria, unclassified_f__Beijerinckiaceae, unclassified_f__Caulobacteraceae, unclassified_c__Bacteroidia and Bosea. Spearman's correlation analysis found Lachnoclostridium, unclassified_f__Rhizobiaceae, Allobaculum, Acinetobacter, Romboutsia, norank_f__Muribaculaceae and Dubosiella showed some correlations with metabolic indicators, inflammation indicators, NAS and occludin. Deletion of the PPARδ gene exacerbated HFD-induced gut microbiota dysbiosis and affected NAFLD through the gut-liver axis.

Feasibility of applying a noninvasive method for sleep monitoring based on mouse behaviors.

INTRODUCTION: Currently, electroencephalogram (EEG)/electromyogram (EMG) system is widely regarded as the "golden standard" for sleep monitoring. Imperfectly, its invasive monitoring may somehow interfere with the natural state of sleep. Up to now, noninvasive methods for sleep monitoring have developed, which could preserve the undisturbed and naïve sleep state of mice to the greatest extent, but the feasibility of their application under different conditions should be extensive validated. METHODS: Based on existing research, we verified the feasibility of a sleep monitoring system based on mouse behaviors under different conditions. The experimental mice were exposed to various stresses and placed into a combined device comprising noninvasive sleep monitoring equipment and an EEG/EMG system, and the sleep status was recorded under different physiological, pharmacological, and pathophysiological conditions. The consistency of the parameters obtained from the different systems was calculated using the Bland-Altman statistical method. RESULTS: The results demonstrated that the physiological sleep times determined by noninvasive sleep monitoring system were highly consistent with those obtained from the EEG/EMG system, and the coefficients were 94.4% and 95.1% in C57BL/6J and CD-1 mice, respectively. The noninvasive sleep monitoring system exhibited high sensitivity under the sleep-promoting effect of diazepam and caffeine-induced wakefulness, which was indicated by its ability to detect the effect of dosage on sleep times, and accurate determination of the sleep/wakeful status of mice under different pathophysiological conditions. After combining the data obtained from all the mice, the coefficient between the sleep times detected by behavior-based sleep monitoring system and those obtained from the EEG/EMG equipment was determined to .94. CONCLUSION: The results suggested that behavior-based sleep monitoring system could accurately evaluate the sleep/wakeful states of mice under different conditions.

Synthesis and clinical application of small-molecule drugs approved to treat prostatic cancer.

Prostate cancer is a prevalent form of cancer that primarily affects men, with a high incidence and mortality rate. It is the second most common cancer among males, following lung cancer. Typically occurring in individuals aged 50 and above, this malignant tumor originates from abnormal cells in the prostate tissue. If left untreated, it can spread to nearby tissues, lymph nodes, and even bones. Current treatment methods include surgery, radiotherapy, and chemotherapy. However, these treatments have certain limitations and side effects. Therefore, researching and developing new small-molecule drugs to treat prostate cancer is of great significance. In recent years, many small-molecule drugs have been proven to have therapeutic effects on prostate cancer. The purpose of this review is to give a comprehensive look at the clinical uses and synthetic methods of various significant small-molecule drugs that have been approved to treat prostate cancer, to facilitate the development of more powerful and innovative drugs for the effective control of prostate cancer.

Synthesis and clinical application of small-molecule inhibitors of Janus kinase.

Janus kinase (JAK) plays a crucial role in intracellular signaling pathways, particularly in cytokine-mediated signal transduction, making them attractive therapeutic targets for a wide range of diseases, including autoimmune disorders, myeloproliferative neoplasms, and inflammatory conditions. The review provides a comprehensive overview of the development and therapeutic potential of small-molecule inhibitors targeting JAK family of proteins in various clinical trials. It also discusses the mechanisms of action, specificity, and selectivity of these inhibitors, shedding light on the challenges associated with achieving target selectivity while minimizing off-target effects. Moreover, the review offers insights into the clinical applications of JAK inhibitors, summarizing the ongoing clinical trials and the Food and Drug Administration (FDA)-approved JAK inhibitors currently available for various diseases. Overall, this review provides a thorough examination of the synthesis and clinical use of typical small-molecule JAK inhibitors in different clinical stages and offers a bright future for the development of novel small-molecule JAK inhibitors.

Advances of clinically approved small-molecule drugs for the treatment of non-small cell lung cancer.

Lung cancer continues to pose a significant challenge as a prominent contributor to global cancer-related mortality. Despite the considerable strides made in therapeutic interventions within the past decade, a substantial population of patients diagnosed with non-small cell lung cancer (NSCLC) still face the grim reality of an incurable condition. In the realm of optimal management strategies for individuals afflicted with locally advanced, yet amenable to surgical resection, NSCLC, a therapeutic approach encompassing chemoradiation stands as a fundamental component. Significant strides have been made in the therapeutic landscape of NSCLC during the preceding two decades, facilitating an enhanced comprehension of the underlying disease biology, and mechanisms governing tumor progression, as well as advancements in early detection modalities and multimodal therapeutic interventions. Nevertheless, the overall rates of curative interventions and survival outcomes for NSCLC continue to exhibit a discouragingly low trajectory, particularly in the context of metastatic disease. Hence, the imperative for sustained research endeavors in the realm of novel pharmaceutical agents and combinatorial therapeutic approaches remains paramount, with the overarching objective of broadening the scope of clinical advantages conferred upon a wider demographic of patients, thereby fostering tangible improvements in outcomes pertaining to NSCLC. The primary objective of this review is to provide an all-encompassing examination encompassing the clinical application and synthetic routes of specific drugs, with the explicit aim of disseminating invaluable knowledge that can inform future research and development endeavors focused on NSCLC.

Synthetic approaches and application of clinically approved small-molecule Anti-HIV drugs: An update.

Application of chemotherapeutic agents to inhibit the HIV replication process has brought about a significant metamorphosis in the landscape of AIDS. Substantial declines in morbidity and mortality rates have been attained, accompanied by notable decreases in healthcare resource utilization. However, treatment modalities do not uniformly inhibit HIV replication in every patient, while the emergence of drug-resistant viral strains poses a substantial obstacle to subsequent therapeutic interventions. Furthermore, chronic administration of therapy may lead to the manifestation of toxicities. These challenges necessitate the exploration of novel pharmacological agents and innovative therapeutic approaches aimed at effectively managing the persistent viral replication characteristic of chronic infection. This review examines the role of clinically approved small-molecule drugs in the treatment of HIV/AIDS, which provides an in-depth analysis of the major classes of small-molecule drugs, including nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), integrase inhibitors, entry inhibitors, and pharmacokinetic enhancers. The review mainly discusses the application, synthetic routes, and mechanisms of action of small-molecule drugs employed in the treatment of HIV, as well as their use in combination with antiretroviral therapy, presenting viewpoints on forthcoming avenues in the development of novel anti-HIV drugs.

Recent advance of clinically approved small-molecule drugs for the treatment of myeloid leukemia.

Myeloid leukemia denotes a hematologic malignancy characterized by aberrant proliferation and impaired differentiation of blood progenitor cells within the bone marrow. Despite the availability of several treatment options, the clinical outlook for individuals afflicted with myeloid leukemia continues to be unfavorable, making it a challenging disease to manage. Over the past, substantial endeavors have been dedicated to the identification of novel targets and the advancement of enhanced therapeutic modalities to ameliorate the management of this disease, resulting in the discovery of many clinically approved small-molecule drugs for myeloid leukemia, including histone deacetylase inhibitors, hypomethylating agents, and tyrosine kinase inhibitors. This comprehensive review succinctly presents an up-to-date assessment of the application and synthetic routes of clinically sanctioned small-molecule drugs employed in the treatment of myeloid leukemia. Additionally, it provides a concise exploration of the pertinent challenges and prospects encompassing drug resistance and toxicity. Overall, this review effectively underscores the considerable promise exhibited by clinically endorsed small-molecule drugs in the therapeutic realm of myeloid leukemia, while concurrently shedding light on the prospective avenues that may shape the future landscape of drug development within this domain.