New Diterpenes with Potential Antitumoral Activity Isolated from Plants in the Years 2017-2022.

Diterpenes represent a wider class of isoprenoids, with more than 18,000 isolated compounds, and are present in plants, fungi, bacteria, and animals in both terrestrial and marine environments. Here, we report on the fully characterised structures of 251 new diterpenes, isolated from higher plants and published from 2017, which are shown to have antitumoral activity. An overview on the most active compounds, showing IC50 < 20 μM, is provided for diterpenes of different classes.

Effects of Regioisomerism on the Antiproliferative Activity of Hydroxystearic Acids on Human Cancer Cell Lines.

A series of regioisomers of the hydroxystearic acid () was prepared, and the effect of the position of the hydroxyl group along the chain on a panel of human cancer cell lines was investigated. Among the various regioisomers, those carrying the hydroxyl at positions 5, 7, and 9 had growth inhibitor activity against various human tumor cell lines, including CaCo-2, HT29, HeLa, MCF7, PC3, and NLF cells. and showed a very weak effect.

()-10-Hydroxystearic Acid: Crystals vs. Organogel.

The chiral ()-10-hydroxystearic acid (()-10-HSA) is a positional homologue of both ()-12-HSA and ()-9-HSA with the OH group in an intermediate position. While ()-12-HSA is one of the best-known low-molecular-weight organogelators, ()-9-HSA is not, but it forms crystals in several solvents. With the aim to gain information on the structural role of hydrogen-bonding interactions of the carbinol OH groups, we investigated the behavior of ()-10-HSA in various solvents.

Magnetic Nanoparticles Coated with ()-9-Acetoxystearic Acid for Biomedical Applications.

The well-known ability to selectively drive nanomagnetic materials coated with anticancer drugs into tumor cells suggested the synthesis and the characterization of magnetic nanoparticles (MNPs) functionalized with ()-9-acetoxystearic acid, the acetic ester of ()-9-hydroxystearic acid (9-HSA), an antiproliferative agent active against different cancer cells. The acyl chloride of ()-9-acetoxystearic acid, synthesized in two steps from 9-HSA, was reacted with (3-aminopropyl)triethoxysilane, chosen as a linker between MNPs and the stearyl moiety. In the last step, the novel amide was bound to magnetite NPs by reaction with silyl groups.

Synthesis, Crystal Structure, and Biological Activity of a Multidentate Calix[4]arene Ligand Doubly Functionalized by 2-Hydroxybenzeledene-Thiosemicarbazone.

The design and synthesis of a novel tert-butyl-calix[4]arene functionalized at 1, 3 positions of the lower rim with two terminal 2-hydroxybenzeledene-thiosemicarbazone moieties is reported. The new ligand with multi-dentate chelating properties was fully characterized by several techniques: ESI-Mass spectroscopy, FT-IR, 1H-NMR, and single crystal X-ray diffraction. The solid state structure confirms that the calix[4]arene macrocycle has the expected open cone conformation, with two opposite phenyl rings inclined outwards with large angles.

Novel lysophosphatidic acid receptor 6 antagonists inhibit hepatocellular carcinoma growth through affecting mitochondrial function.

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers worldwide and the commonest liver cancer. It is expected to become the third leading cause of cancer-related deaths in Western countries by 2030. Effective pharmacological approaches for HCC are still unavailable, and the currently approved systemic treatments are unsatisfactory in terms of therapeutic results, showing many side effects.

Design of a Thiosemicarbazide-Functionalized Calix[4]arene Ligand and Related Transition Metal Complexes: Synthesis, Characterization, and Biological Studies.

In this study, we synthesized a new thiosemicarbazide-functionalized calix[4]arene and its Co, Ni, Cu, and Zn transition metal complexes. For characterization several techniques were employed: Fourier-transform infrared (FT-IR), H nuclear magnetic resonance (NMR), C-NMR, N-NMR, correlation spectroscopy (COZY), nuclear Overhauser enhancement spectroscopy (NOESY), electrospray ionization (ESI)-mass spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and elemental analysis. To explore the capability of the thiosemicarbazide function hosted on a calix[4]arene scaffold for growth inhibition of bacteria, fungi, and cancerous tumor cells, a series of biological evaluations were performed.

X-Ray Crystal Structures and Organogelator Properties of -9-Hydroxystearic Acid.

-9-hydroxystearic acid, -9-HSA, is a chiral nonracemic hydroxyacid of natural origin possessing interesting properties as an antiproliferative agent against different cancer types. Considering its potential application for medical and pharmaceutical purposes, the structures and rheological properties of -9-HSA were investigated. Oscillatory rheology measurements reveal that -9-HSA gels only paraffin oil, with less efficiency and thermal stability than its positional isomer -12-HSA.

Enzymatic resolution of α-methyleneparaconic acids and evaluation of their biological activity.

Both enantiomers of three biologically relevant paraconic acids-MB-3, methylenolactocin, and C75-were obtained with enantioselectivities up to 99% by kinetic enzymatic resolutions. Good enantiomeric excesses were obtained for MB-3 and methylenolactocin, using α-chymotrypsin and aminoacylase as enantiocomplementary enzymes, while C75 was resolved with aminoacylase. They all were evaluated for their antiproliferative, antibacterial, and antifungal activities, showing weak effects and practically no difference between enantiomers in each case.

Synthesis, enzymatic resolution, and stereochemical characterization of isoparaconic acid derivatives: a combined experimental and theoretical investigation.

Enantiomerically enriched isoparaconic acid derivatives were obtained by kinetic enzymatic resolution. To explain the solvent dependence observed for their optical rotatory power a computational investigation of their chiroptical properties was performed.

On the dichotomic behavior of the Z-2,4-dinitrophenylhydrazone of 5-amino-3-benzoyl-1,2,4-oxadiazole with acids in toluene and in dioxane/water: rearrangement versus hydrolysis.

The mononuclear rearrangement (MRH) of the Z-2,4-dinitrophenylhydrazone (4a) and of the Z-phenylhydrazone (4b) of 5-amino-3-benzoyl-1,2,4-oxadiazole into the relevant triazoles 5a and 5b in toluene has been quantitatively investigated in the presence of trichloroacetic acid (TCA) and of piperidine at 313.1 K. While the behavior in the presence of piperidine recalls the one previously evidenced for some Z-hydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole, the study of the reactivity in the presence of TCA has most interestingly evidenced a general-acid-catalyzed rearrangement for "both" 4a and 4b.