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Quorum sensing (QS) is a bacterial cell-to-cell communication mechanism that plays an essential role in bacterial pathogenesis. QS governs bacterial behavior and controls biofilm formation, which in turn contributes to antibiotic resistance. Therefore, identifying and synthesizing novel compounds to overcome QS and inhibit biofilm formation are essential. Coumarins are important plant-derived natural products with wide-ranging bioactivities and extensive applications, including antibacterial, antifungal, anticoagulant, antioxidant, anticancer, and anti-inflammatory properties. Additionally, coumarins are capable of QS rewiring and biofilm formation inhibition, leading to higher susceptibility to antimicrobial agents and less antibiotic resistance. Therefore, in this review, we aim to provide an overview of QS and biofilm formation. This review also discusses the role of natural and synthesized coumarins in controlling QS, inhibiting biofilm formation, and inducing synergy in antibiotic–coumarin combinations. Hence, this review emphasizes the potential of coumarin compounds to act as antibacterial agents and demonstrates their ability to alleviate antibiotic resistance. [ABSTRACT FROM AUTHOR]

The investigation of natural products used in Traditional Medicine in Africa is complicated as modern analytical and screening methods are often not available. Computer aided product identification from traditional usage records (CAPITURE) may provide an interesting alternative and has been evaluated in the context of an ethnobotanical survey on fungal diseases and their traditional treatment in Tchamba District (Togo). 53 traditional healers were interviewed and their knowledge recorded. Several indicators, the Use Value (UV), Plant Part Value (PPV), Specific Use (SU) Value, Intraspecific Use Value (IUV) and Informant Consensus Factor (ICF), were applied to the data. Those indices, in addition to a bibliographic review, were then fed into a computer-aided approach which predicted two interesting plants out of the 43 species survey-recorded and their specific activities: Pterocarpus erinaceus sap against ringworm, Daniellia oliveri sap against intertrigo and respectively their roots and trunk barks against candidiasis. Subsequent laboratory-based studies have confirmed the predicted antimicrobial activities with MIC (128 μg/mL to 30 mg/mL) and without any notable toxicity on a normal human cell (MRC-5 cells). Although such a method may not be flawless, it is able to provide first leads, and in the face of limited resources, is an attractive alternative worth considering.

Asteltoxins belong to a group of polyene pyrone mycotoxins that are known to be potent inhibitors of mitochondrial ATP synthesis and ATP hydrolysis. Asteltoxin A was first isolated from the toxic maize cultures of Aspergillus stellatus. Several attempts have been made to synthesize asteltoxin A, starting with the synthesis of a bis(tetrahydrofuran) moiety that has been demonstrated previously in biosynthetic studies. This review highlights the fungal sources of asteltoxins, similar asteltoxins, biosynthetic pathways, their synthetic trials, and their biological activities. This review is the first of its kind covering the periods from 1979 to 2023. [ABSTRACT FROM AUTHOR]

Fungal bioactive secondary metabolites are considered promising sources for the production of unique compounds with exceptional chemical structures. Of these bioactive secondary metabolites, meleagrins are prenylated indole alkaloids characterized by a triazaspirocyclic skeleton that is generally obtained from Penicillium species. Meleagrins are alkaloids with promising biological activities. Here is a survey of previously published research on meleagrins: their sources, biosynthetic pathways, synthesis, and bioactivities. [ABSTRACT FROM AUTHOR]

Marine products are among the most promising sources of biologically active molecules. Aplysinopsins, tryptophan-derived marine natural products, were isolated from different natural marine sources including sponges, stony corals (hard corals) especially genus scleractinian, as well as sea anemone, in addition to one nudibranch. Aplysinopsins were reported to be isolated from different marine organisms related to various geographic areas such as Pacific, Indonesia, Caribbean, and Mediterranean regions. This review gives an up-to-date overview of marine alkaloid aplysinopsins: their various sources, their synthesis, and the fact that many aplysinopsin derivatives are biologically active compounds. [ABSTRACT FROM AUTHOR]

Aplysinopsins are a class of indole alkaloids that possess various pharmacological activities. Although their action has been studied in regard to many diseases, their effect on prostate cancer has not yet been examined. Therefore, we synthesized a new series of aplysinopsin analogs and investigated their cytotoxic activity against prostate cancer. Five analogs showed high antitumor activity via suppressing the expression of the anti-apoptotic gene Bcl2, simulationously increasing the expression of the pro-apoptotic genes p53, Bax and Caspase 3. The inhibition of BCL2 led to the activation of BAX, which in turn activated Caspase 3, leading to apoptosis. This dual mechanism of action via apoptosis and cell cycle arrest induction is responsible for aplysinopsin analogs antitumor activity. Hence, our newly synthesized analogs are highly promising candidates for further preclinical studies against prostate cancer. [ABSTRACT FROM AUTHOR]

In consideration of green and efficient organic chemical methodology, we reported here a green, an efficient and convenient procedure for synthesis of 3-aryl-2,3-dihydro-1,3,4-thiadiazoles based on benzofuran as well as chromone moieties, using the grinding technique. Condensation of 1-(4,7-dimethoxybenzofuran-5-yl)ethan-1-ones 2, 3; 7-hydroxy-5-methoxy-2-methyl-4-oxo-4H-chromene-6-carbaldehyde (4); and 4-oxo-4H-chromene-3-carbaldehydes 10a–c with alkyl hydrazine carbodithioates followed with some hydrazonoyl halides 7a–g under grinding and solvent-free condition led to the formation of the targeted 3-aryl-2,3-dihydro-1,3,4-thiadiazoles 8a–g, 9a,b, and 12a–f, correspondingly. Structures of the synthesized compounds were clarified based on their elemental analyses and spectral data. Eleven of the entire target compounds were selected for anticancer activity against 60 human cancer cell lines at a single dose (10‾5 M) by the National Cancer Institute (NCI, Bethesda, USA). [ABSTRACT FROM AUTHOR]

Abstract: The regioselective Friedlander reaction of 3-amino-4-cyanopyrroles with a series of cyclic ketones has enabled the first reported synthesis of substituted 4-azaisoindoles. Structurally, this new class of compounds stands for [...]