Jaursup Boonmak

A new lumazine peptide penilumamide E from the fungus Aspergillus terreus

Abstract A new rare lumazine peptide, penilumamide E (1), together with 13 known compounds (2–14) were isolated from the fungus Aspergillus terreus. Their structures were identified by spectroscopic techniques. The relative configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 10 exhibited antimalarial activity against Plasmodium falciparum with IC50 values of 2.83 μg/mL. Compounds 4 and 6 showed weak cytotoxicity against cholangiocarcinoma (CCA) cell lines. In addition, 4 and 11 exhibited weak cytotoxicity against human hepatoma cell line. Graphical abstract

Tuning the nuclearity of iron(III) polynuclear clusters by using tetradentate Schiff-base ligands

Three novel octanuclear, hexanuclear and tetranuclear complexes of high-spin Fe(III) ions were obtained by the reaction of the N,N′-bis-(1R-imidazol-4-ylmethylene)-ethane-1,2-diamine ligand (R = H, CH3) and its derivatives with Fe(ClO4)3·6H2O and KSCN. The tetradentate Schiff-base ligand acts as a bis(bidentate) chelating bridge between two adjacent high-spin Fe(III) centers. The presence of a methyl group in the imidazolyl substituent, the change of counterions or the replacement of imidazole by pyridine has a drastic effect on the nuclearity of the cluster. The magnetic properties of all compounds exhibit antiferromagnetic interactions via μ-oxo or μ-hydroxo pathways in Fe(III) dimers.

Three-dimensional Organometallic Thallium(I) Supramolecular Polymer Nanostructures Synthesized with Sonochemical Process

A new three-dimensional thallium(I) supramolecular polymer, [Tl2(μ2-ATA)]n (1), [H2ATA=2-aminoterephthalic acid], has been synthesized and characterized. The single-crystal X-ray data of compound 1 shows one type of TlI ion with a low coordination number. Compound 1 was self-assembled from Tl⋯C, Tl⋯O and Tl⋯N secondary interactions in thallium(I) coordination and the active lone pair on TlI in this compound may be involved in donor bonding. Two sides of the aromatic ring of ATA2- anion have been involved in two types of secondary Tl⋯C approaches. Three samples of 1 were synthesized with three different concentrations of initial reagents under ultrasonic irradiation. The thermal stability of compound 1 samples were studied by thermo gravimetric (TG) and differential thermal analyses (DTA). These nano-structures were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM).

Bicyclic lactones and racemic mixtures of dimeric styrylpyrones from the leaves of Miliusa velutina

A unique class of eight bicyclic lactones with a C18 carbon architecture, named velutinones A–H (1–8), three new dimeric styrylpyrones, velutinindimers A–C (9–11), five known compounds, the kawapyrone, yangonin (12), three flavonoids (13–15), and an acetogenin, cananginone H (16) were isolated from the leaves of Miliusa velutina. The absolute configurations of 2 and 5 were assigned by Moshers method, whereas ECD, optical rotations, and X-ray crystallographic analysis indicated the racemic nature of compounds 10 and 11. Compounds 2–4 and 7–11 showed antimalarial activity with IC50 values in the range of 5.4–10.0 μM. Moreover, 1–4 and 6–8 displayed cytotoxicity against the KB, MCF7, and NCI-H187 cancer cell lines and Vero cell lines with IC50 values in the range of 4.0–24.1 μM.

Chemical constituents and cytotoxic activity from the wood-decaying fungus Xylaria sp. SWUF08-37

Abstract A new cyclic pentapeptide, pentaminolarin (1), and a new cytochalasin, xylochalasin (2), along with thirteen known compounds (3–15) were isolated from the wood-decaying fungus Xylaria sp. SWUF08-37. The absolute configurations of 1 were determined by a combination of Marfey’s method and TDDFT ECD calculation and the absolute configurations of 2 were established by TDDFT ECD calculation. Compound 12 showed moderate cytotoxicity against HeLa (IC50 = 19.60 µg/mL), HT29 (IC50 = 17.31 µg/mL), HCT116 (IC50 = 14.28 µg/mL), MCF-7 (IC50 = 15.38 µg/mL), and Vero (IC50 = 24.97 µg/mL) cell lines by MTT assay. Compounds 1 and 2 showed slight cytotoxicity against all tested cancer cell lines. Graphical Abstract

Bioactive Lupane and Hopane Triterpenes from Lepisanthes senegalensis

Two lupane and hopane caffeates (1 and 4) and two hopane coumarates (2 and 3) along with eight known compounds (5-12) were isolated from stems and roots of Lepisanthes senegalensis. Their structures were established on the basis of spectroscopic techniques. The structure of compound 2 was confirmed by single-crystal X-ray diffraction analysis. Triterpenes 1 and 4-6 showed cytotoxicity against the NCI-H187 cell line with IC50 values of 31.5, 28.5, 16.2, and 4.0 µM, respectively. However, these compounds also showed cytotoxicity against Vero cells, with IC50 values of 75.5, 16.6, 8.9, and 5.0 µM, respectively. In addition, compound 6 exhibited a moderate antimalarial activity with an IC50 value of 4.5 µM.

Crystal structure of (μ-N-allyl­thio­urea-κ2S:S)bis­[μ-bis­(di­phenyl­phosphanyl)methane-κ2P:P′]bis­[bromido­copper(I)] aceto­nitrile disolvate

In the solvated dinuclear complex [Cu2Br2(ATU)(dppm)2]·2CH3CN, both Cu+ ions adopt distorted tetrahedral geometries, being coordinated by one terminal Br atom, one μ2-S atom of the bridging ATU ligand and two P atoms of the bridging dppm ligands. Within the complex, intramolecular C—H⋯S, C—H⋯π, N—H⋯Br and π–π stacking interactions are observed. In the crystal, the components are linked by N—H⋯Br and C—H⋯N hydrogen bonds and weak π–π stacking interactions, generating chains propagating in the [100] direction.

Crystal structure of (μ-N-allylthiourea-κ2S:S)bis[μ-bis(diphenylphosphanyl)methane-κ2P:P′]bis[bromidocopper(I)] acetonitrile disolvate

In the solvated dinuclear complex [Cu2Br2(ATU)(dppm)2]·2CH3CN, both Cu+ ions adopt distorted tetrahedral geometries, being coordinated by one terminal Br atom, one μ2-S atom of the bridging ATU ligand and two P atoms of the bridging dppm ligands. Within the complex, intramolecular C—H⋯S, C—H⋯π, N—H⋯Br and π–π stacking interactions are observed. In the crystal, the components are linked by N—H⋯Br and C—H⋯N hydrogen bonds and weak π–π stacking interactions, generating chains propagating in the [100] direction.

Crystal structure of (μ-N-allyl-thio-urea-κ(2) S:S)bis-[μ-bis-(di-phenyl-phosphanyl)methane-κ(2) P:P']bis-[bromido-copper(I)] aceto-nitrile disolvate.

In the solvated dinuclear complex [Cu2Br2(ATU)(dppm)2]·2CH3CN, both Cu+ ions adopt distorted tetrahedral geometries, being coordinated by one terminal Br atom, one μ2-S atom of the bridging ATU ligand and two P atoms of the bridging dppm ligands. Within the complex, intramolecular C—H⋯S, C—H⋯π, N—H⋯Br and π–π stacking interactions are observed. In the crystal, the components are linked by N—H⋯Br and C—H⋯N hydrogen bonds and weak π–π stacking interactions, generating chains propagating in the [100] direction.