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Carotane sesquiterpenes are commonly found in plants but are infrequently reported in the fungal kingdom. Chemical investigation of Trichoderma virens QA-8, an endophytic fungus associated with the inner root tissue of the grown medicinal herb Artemisia argyi H. Lév. and Vaniot, resulted in the isolation and characterization of five new carotane sesquiterpenes trichocarotins I–M (1–5), which have diverse substitution patterns, and seven known related analogues (6–12). The structures of these compounds were established on the basis of a detailed interpretation of their NMR and mass spectroscopic data, and the structures including the relative and absolute configurations of compounds 1–3, 5, 9, and 10 were confirmed by X-ray crystallographic analysis. In the antibacterial assays, all isolates exhibited potent activity against Escherichia coli EMBLC-1, with MIC values ranging from 0.5 to 32 µg/mL, while 7β-hydroxy CAF-603 (7) strongly inhibited Micrococcus luteus QDIO-3 (MIC = 0.5 µg/mL). Structure-activity relationships of these compounds were discussed. The results from this study demonstrate that the endophytic fungus T. virens QA-8 from the planted medicinal herb A. argyi is a rich source of antibacterial carotane sesquiterpenes, and some of them might be interesting for further study to be developed as novel antibacterial agents.

In the crystal structure of the title compound, C20H16O4, which is in the enol form, the central benzene ring makes dihedral angles of 63.42 (9) and 5.19 (10)° with the phenyl and furan rings, respectively. There is a short strong intramolecular O—H...O hydrogen bond.

Twelve novel triazolothiadiazole derivatives were synthesized from 4-amino-5-substituted-4H-1,2,4-triazole-3-thiols with various aromatic carboxylic acids by cyclization in the presence of phosphorous oxychloride. All the newly synthesized compounds were characterized by FTIR, ¹H NMR, mass spectroscopy and elemental analysis. The antimicrobial activities of the title compounds were examined by disc diffusion method against Escherichia coli, Staphylococcus aureus, Pyricularia oryzae and Rhizoctnia solani. The bioassay indicated all synthesized triazolothiadiazole derivatives possessed moderate to good antibacterial and antifungal activities against the tested organisms. Especially, compounds 2e and 2k exhibited excellent antibacterial and antifungal activities among these triazolothiadiazole derivatives. [ABSTRACT FROM AUTHOR]

A new Co(II) complex 2 with ligand 4,4,4-trifluoro-1-(6-methoxynaphthalen-2-yl) butane-1,3-dione 1 and pyridine are prepared and crystallized from an acetone solution. The obtained red and transparent crystal conforms to the empirical formula of Co(CHOF)·(CHN). It crystallizes in monoclinic, space group C2/c with a = 23.3152(14), b = 12.0225(7), c = 15.3950(10) Å, β = 124.1360(10)°, V = 3571.8(4) Å, Z = 4, CHCoFNO, Mr = 807.59, F(000) = 1652, Dc = 1.502 g/cm, μ = 0.564 mm, the final R = 0.0466 and wR = 0.1043 for 3901 observed reflections with I > 2σ(I). X-ray structural analysis revealed that the Co(II) atom is coordinated by two oxygen atoms of 1,3-dione ligands 1 and two nitrogen atoms of pyridines, forming a distorted octahedron coordination geometry. Graphical Abstract: A new cobalt complex 2 bis(pyridine)bis(4,4,4-trifluoro-1-(6-methoxynaphthalen-2-yl)butane-1,3-dione) Cobalt(II), Co(CHOF)·(CHN), has been synthesized and characterized by X-ray structure determination. In the complex, the Co(II) atom is coordinated by four oxygen atoms of the β-diketonate ligands and two nitrogen atoms of pyridines, forming a distorted octahedron coordination geometry.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Two new 3,5-diaryl-1 H-pyrazoles: 3(5)-(4-tert-butylphenyl)-5(3)-(naphthalene-2-yl)-1 H-pyrazole ( 1) and 5-(4-(benzyloxy)phenyl)-3-(furan-2-yl)-1 H-pyrazole ( 2) were synthesized and characterized. Two strong ions peaks [2M] and [2M + Na] observed in the ESI-MS spectra are attributed to the dimerization process in solution formed by intermolecular N-H···N hydrogen bonds. The crystal structures have been determined by X-ray crystal structure analysis. Compound 1 exists as a pair of tautomers 1a and 1b, and its dimer [ R(6) motif] is formed by the tautomers 1a and 1b. Compound 2 only exists as a 2a tautomer, and interesting intermolecular N-H···O and O-H···N hydrogen bonds link two pyrazoles and two methanol molecules, leading to the formation of an R(10) dimer motif. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C23H22O2, which exists in the enol form, is stabilized by an intramolecular hydrogen bond. The dihedral angle between the naphthyl ring system and the aromatic ring of the t-BuC6H4 group is 23.50 (10)°. [ABSTRACT FROM AUTHOR]

The molecule of the title compound, C17H13F3O3, exists in the enol form and displays a strong intramolecular O—H...O hydrogen bond. The trifluoromethyl group is disordered over two orientations in an approximate 2:1 ratio. [ABSTRACT FROM AUTHOR]

The molecules of the title compound, C25H24N2, are connected by intermolecular N—H...N hydrogen bonds to form dimers. The crystal packing is stabilized by van der Waals forces. [ABSTRACT FROM AUTHOR]

In the title compound, C25H24O2, the molecular structure exists in a cis-enol form which is stabilized by an intramolecular O—H...O hydrogen bond. This hydrogen bond is described as an approximately symmetrical hydrogen bond. The three methyl groups are disordered over two positions, with a site occupancy ratio of ca 4:1. [ABSTRACT FROM AUTHOR]