Concise synthesis and antiproliferative activity evaluation of ellipticine quinone and its analogs

2-Amino-1,4-naphthoquinone as a key precursor for naphthoquinone-fused N-heterocycles: synthetic approaches and mechanistic perspectives

2-Amino-1,4-naphthoquinone has gained significant attention as a key precursor for constructing naphthoquinone-fused N-heterocycles, a class of compounds with broad applications in medicinal chemistry, materials science, and organic synthesis. Its unique structure, characterized by a reactive C-3 position and an amino group, facilitates a wide range of reactions and synthetic strategies. This review provides a comprehensive overview of recent advancements (2012-2024) in utilizing 2-amino-1,4-naphthoquinone for the development of N-heterocyclic frameworks integrating synthetic approaches with mechanistic insights. It is organized based on the type of heterocyclic rings formed, leveraging the C,N-binucleophilic properties of 2-amino-1,4-naphthoquinone.

Authenticity and Bioactive Markers Search in the Phenolic-Rich Extracts of Asteraceae Medicinal Plants Through Integrative Computational Chemometrics

The Asteraceae family has been of significant concern for ethnobotanical studies, thanks to its health-promoting properties linked to a plethora of bioactive compounds, among which phenolic compounds play a critical role. In this work, a workflow based on computational chemometrics was employed to assess the authenticity and biomarker search of five key Asteraceae species commonly employed in traditional medicine. The UHPLC-DAD-ESI/MS-MS phenolic profile of Asteraceae extracts was combined with the evaluation of several in vitro biological properties. Caffeoylquinic acids (CQAs), chicoric acids, and flavonoid glycosides were reported as authenticity markers of Achillea millefolium, Taraxacum officinale, and Arnica montana, respectively. The integration of phenolic profile and in vitro bioactivities provide insights for the identification of trans 3,5-O-dicaffeoylquinic acid (3,5-O-diCQA) and isorhamnetin glycosides as the major antioxidant agents in Asteraceae extracts, whereas several CQAs and caffeoyl-deoxy-octulopyranosonic acids have been reported as responsible for their cytotoxic and anti-inflammatory activities. These results shed light on the authentication and quality evaluation of Asteraceae extracts, along with the characterization of their functional properties, leading to their application in the design of novel plant-based functional foods.

Advances in heterocycles as DNA intercalating cancer drugs

The insertion of a molecule between the bases of DNA is known as intercalation. A molecule is able to interact with DNA in different ways. DNA intercalators are generally aromatic, planar, and polycyclic. In chemotherapeutic treatment, to suppress DNA replication in cancer cells, intercalators are used. In this article, we discuss the anticancer activity of 10 intensively studied DNA intercalators as drugs. The list includes proflavine, ethidium bromide, doxorubicin, dactinomycin, bleomycin, epirubicin, mitoxantrone, ellipticine, elinafide, and echinomycin. Considerable structural diversities are seen in these molecules. Besides, some examples of the metallo-intercalators are presented at the end of the chapter. These molecules have other crucial properties that are also useful in the treatment of cancers. The successes and limitations of these molecules are also presented.

[Development of New Synthetic Methods for Carbazole Compounds Aimed at Drug Discovery and Exploratory Research on Pharmaceutical Materials]

We are developing the synthesis of biologically interesting carbazole compounds, including natural products by tandem cyclic reactions. In this report, we describe the new synthesis of carbazole-1,4-quinones as follows; 1) the synthesis of carbazole-1,4-quinones using a tandem ring closing metathesis (RCM) -dehydrogenation reaction, 2) a novel one-pot synthesis of carbazole-1,4-quinone by consecutive Pd-catalyzed cyclocarbonylation, desilylation, and oxidation reactions. Two new synthetic strategies were applied to the synthesis of carbazole-1,4-quinone alkaloids and ellipticine quinones, and then the antiproliferative activity against HCT-116 and HL-60 cells of the synthesized compounds were evaluated.

Total synthesis of pyrrolo[2,3-c]quinoline alkaloid: trigonoine B

The first total synthesis of the pyrrolo[2,3-c]quinoline alkaloid trigonoine B (1) was accomplished via a six-step sequence involving the construction of an N-substituted 4-aminopyrrolo[2,3-c]quinoline framework via electrocyclization of 2-(pyrrol-3-yl)benzene containing a carbodiimide moiety as a 2-azahexatriene system. The employed six-step sequence afforded trigonoine B (1) in 9.2% overall yield. The described route could be employed for the preparation of various N-substituted 4-aminopyrroloquinolines with various biological activities.

Identification of novel dynamin-related protein 1 (Drp1) GTPase inhibitors: Therapeutic potential of Drpitor1 and Drpitor1a in cancer and cardiac ischemia-reperfusion injury

Mitochondrial fission is important in physiological processes, including coordination of mitochondrial and nuclear division during mitosis, and pathologic processes, such as the production of reactive oxygen species (ROS) during cardiac ischemia-reperfusion injury (IR). Mitochondrial fission is mainly mediated by dynamin-related protein 1 (Drp1), a large GTPase. The GTPase activity of Drp1 is essential for its fissogenic activity. Therefore, we aimed to identify Drp1 inhibitors and evaluate their anti-neoplastic and cardioprotective properties in five cancer cell lines (A549, SK-MES-1, SK-LU-1, SW 900, and MCF7) and an experimental cardiac IR injury model. Virtual screening of a chemical library revealed 17 compounds with high predicted affinity to the GTPase domain of Drp1. In silico screening identified an ellipticine compound, Drpitor1, as a putative, potent Drp1 inhibitor. We also synthesized a congener of Drpitor1 to remove the methoxymethyl group and reduce hydrolytic lability (Drpitor1a). Drpitor1 and Drpitor1a inhibited the GTPase activity of Drp1 without inhibiting the GTPase of dynamin 1. Drpitor1 and Drpitor1a have greater potency than the current standard Drp1 GTPase inhibitor, mdivi-1, (IC50 for mitochondrial fragmentation are 0.09, 0.06, and 10 μM, respectively). Both Drpitors reduced proliferation and induced apoptosis in cancer cells. Drpitor1a suppressed lung cancer tumor growth in a mouse xenograft model. Drpitor1a also inhibited mitochondrial ROS production, prevented mitochondrial fission, and improved right ventricular diastolic dysfunction during IR injury. In conclusion, Drpitors are useful tools for understanding mitochondrial dynamics and have therapeutic potential in treating cancer and cardiac IR injury.