Dihydropyrimidinones as potent anticancer agents: Insight into the structure-activity relationship

Cancer is a serious disease that has been around for a long time but currently has no sustainable solution. Several medications currently available offer an opportunity for the manifestation of cancer treatment; however, the "search for better" has led to the development and study of a variety of new scaffolds. Dihydropyrimidinones (DHPMs) are a privileged scaffold, prominent for their versatile range of biological activities. In recent years, the anticancer potential of these unsaturated pyrimidine ring systems has been traversed, along with their synthesis methods and the interlinked mechanisms leading to the anticancer activity. This review summarizes the structure-activity relationship of DHPMs as potential anticancer agents. This study is a short review of their synthesis, mechanism of action, and structure-activity relationships (SARs) that are answerable for the anticancer activity of DHPMs and have been thoroughly researched and assessed.

Spirocyclic derivatives as antioxidants: a review

In recent years, spiro compounds have attracted significant interest in medicinal chemistry due to their numerous biological activities attributed primarily to their versatility and structural similarity to important pharmacophore centers. Currently, the development of drugs with potential antioxidant activities is of great importance since numerous investigations have shown that oxidative stress is involved in the development and progression of numerous diseases such as cancer, senile cataracts, kidney failure, diabetes, high blood pressure, cirrhosis, and neurodegenerative diseases, among others. This article provides an overview of the synthesis and various antioxidant activities found in naturally occurring and synthetic spiro compounds. Among the antioxidant activities reviewed are DPPH, ABTS, FRAP, anti-LPO, superoxide, xanthine oxidase, peroxide, hydroxyl, and nitric oxide tests, among others. Molecules that presented best results for these tests were spiro compounds G14, C12, D41, C18, C15, D5, D11, E1, and C14. In general, most active compounds are characterized for having at least one oxygen atom; an important number of them (around 35%) are phenolic compounds, and in molecules where this functional group was absent, aryl ethers and nitrogen-containing functional groups such as amine and amides could be found. Recent advances in the antioxidant activity profiles of spiro compounds have shown that they have a significant position in discovering drugs with potential antioxidant activities.

This article provides an overview of the synthesis and various antioxidant activities found in naturally occurring and synthetic spiro compounds.

Engaging Isatins in Multicomponent Reactions (MCRs) - Easy Access to Structural Diversity

Multicomponent reactions (MCRs) are a valuable tool in diversity-oriented synthesis. Its application to privileged structures is gaining relevance in the fields of organic and medicinal chemistry. Isatin, due to its unique reactivity, can undergo different MCRs, affording multiple interesting scaffolds, namely oxindole-derivatives (including spirooxindoles, bis-oxindoles and 3,3-disubstituted oxindoles) and even, under certain conditions, ring-opening reactions occur that leads to other heterocyclic compounds. Over the past few years, new methodologies have been described for the application of this important and easily available starting material in MCRs. In this review, we explore these novelties, displaying them according to the structure of the final products obtained.

Hollow Magnetic Nanocatalysts Drive Starvation-Chemodynamic-Hyperthermia Synergistic Therapy for Tumor

Magnetic hyperthermia therapy (MHT) has been considered as an excellent alternative for treatment of deep tumor tissue; however, up-regulation of heat shock proteins (HSPs) impairs its hyperthermal therapeutic effect. Reactive oxygen species (ROS) and competitive consumption of ATP are important targets that can block excessive HSP generation. We developed a magnetic nanocatalytic system comprised of glucose oxidase (GOD)-loaded hollow iron oxide nanocatalysts (HIONCs) to drive starvation-chemodynamic-hyperthermia synergistic therapy for tumor treatment. The Fe²⁺ present in HIONCs contributed to ROS generation via the Fenton reaction, relieving thermo-resistance and inducing cell apoptosis by chemodynamic action. The Fenton effect was enhanced through the conditions created by increased MHT-related temperature, GOD-mediated H₂O₂ accumulation, and elevated tumor microenvironment acidity. The HIONCs catalase-like activity facilitated conversion of H₂O₂ to oxygen, thereby replenishing the oxygen levels. We further demonstrated that locally injected HIONCs-GOD effectively inhibited tumor growth in PC3 tumor-bearing mice. This study presents a multifunctional nanocarrier system driving starvation-chemodynamic-magnetic-thermal synergistic therapy via ROS and oxygen modulation for prostate tumor treatment.

An overview of spirooxindole as a promising scaffold for novel drug discovery

Introduction: Spirooxindole, a unique and versatile scaffold, has been widely studied in some fields such as pharmaceutical chemistry and synthetic chemistry. Especially in the application of medicine, quite a few compounds featuring spirooxindole motif have displayed excellent and broad pharmacological activities. Many identified candidate molecules have been used in clinical trials, showing promising prospects.Areas covered: This article offers an overview of different applications and developments of spirooxindoles (including the related natural products and their derivatives) in the process of drug innovation, including such as in anticancer, antimicrobial, anti-inflammatory, analgesic, antioxidant, antimalarial, and antiviral activities. Furthermore, the crucial structure-activity relationships, molecular mechanisms, pharmacokinetic properties, and main synthetic methods of spirooxindoles-based derivatives are also reviewed.Expert opinion: Recent progress in the biological activity profiles of spirooxindole derivatives have demonstrated their significant position in present-day drug discovery. Furthermore, we believe that the multidirectional development of novel drugs containing this core scaffold will continue to be the research hotspot in medicinal chemistry in the future.