A new series of coumarin-1,2,3-triazole conjugates with varied alkyl, phenyl and heterocycle moieties at C-4 of the triazole nucleus were synthesized using a copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reaction of corresponding O-propargylated coumarin (3) or N-propargylated coumarin (6) with alkyl or aryl azides. Based on their minimal inhibitory concentrations (MICs) against selected microorganisms, six out of twenty-six compounds showed significant antibacterial activity towards Enterococcus faecalis (MIC = 12.5–50 µg/mL). Moreover, the synthesized triazoles show relatively low toxicity against human erythrocytes.

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A new series of furan embelin derivatives was synthesized and characterized as ATPcompetitive CK2 inhibitors. The new compounds were efficiently synthesized using a multicomponent approach from embelin (1), aldehydes and isonitriles through a Knoevenagel condensation/ Michael addition/ heterocyclization. Several compounds with inhibitory activities in the low micromolar or even submicromolar were identified.The most active derivative was compound 4l (2-(tert-butylamino)-3-(furan-3-yl)-5hydroxy-6-undecylbenzofuran-4,7-dione) with an IC 50 value of 0.63 µM. It turned out to be an ATP competitive CK2 inhibitor with a K i value determined to be 0.48 µM.Docking studies allowed the identification of key ligand-CK2 interactions, which could help to further optimize this family of compounds as CK2 inhibitors.

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A series of nine derivatives (2–10) were prepared from the diterpene solidagenone (1) and their structures were elucidated by means of spectroscopic studies. Their ability to inhibit inflammatory responses elicited in peritoneal macrophages by TLR ligands was investigated. Compounds 5 and 6 showed significant anti-inflammatory effects, as they inhibited the protein expression of nitric oxide synthase (NOS-2), cyclooxygenase-2 (COX-2), and cytokine production (TNF-α, IL-6, and IL-12) induced by the ligand of TLR4, lipopolysaccharide (LPS), acting at the transcriptional level. Some structure–activity relationships were outlined. Compound 5 was selected as a representative compound and molecular mechanisms involved in its biological activity were investigated. Inhibition of NF-κB and p38 signaling seems to be involved in the mechanism of action of compound 5. In addition, this compound also inhibited inflammatory responses mediated by ligands of TLR2 and TLR3 receptors. To rationalize the obtained results, molecular docking and molecular dynamic studies were carried out on TLR4. All these data indicate that solidagenone derivative 5 might be used for the design of new anti-inflammatory agents.

Derivatives 24-34 bearing both a 4-ketone and a 27-silyl ether group were prepared from compound 23 by silylation at C-27 with different silyl chloride reagents as shown in Scheme 4 (Supporting Information, S41-S46). Scheme 4. Synthesis of 4-Oxo-withaferin A-silyl Ether Analogues 24-34 a a Reagents and conditions: (i) R 1 R 2 R 3 SiCl, imidazol, DMAP, CH 2 Cl 2 , rt.

Three new benzodihydrofurans (1-3) and seven known aromatic compounds (4-10) were isolated from the roots of Cyperus teneriffae. Vibrational circular dichroism spectroscopy was used to define the absolute configuration of 1.