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From the fresh leaves of Koelreuteria paniculata Laxm (Sapindaceae), four new compounds, named ethyl p -trigallate ( 1 ), 3″- O -galloyl-4′- O -galloyl-4- O -galloyl-gallic acid ( 2 ), ethyl p -heptagallate ( 3 ) and 3″-galloylquercitrin ( 4 ), together with 12 known compounds namely catechin ( 5 ), galloylepicatechin ( 6 ), isorhamnetin ( 7 ), kaempferol-3- O -arabinopyranoside ( 8 ), quercetin-3′- O -β- d -arabinopyranoside ( 9 ), quercitrin ( 10 ), methyl p -digallate ( 11 ), methyl m -digallate ( 12 ), p -digalloyl acid ( 13 ), m -digalloyl acid ( 14 ), hyperin ( 15 ) and kaempferol-3- O -α- l -rhamnoside ( 16 ) were isolated by extensive column chromatographic separation. Their structures were elucidated on the basis of chemical and spectroscopic methods. Compound 9 was not reported previously with pyranoside of arabinose at C-3′. Compounds 4 and 9 possessed the activity for PTK inhibition. [ABSTRACT FROM AUTHOR]

A series of new benzophenone and diphenylmethane halophenol derivatives were prepared. Their structures were established based on 1H NMR, 13C NMR and HRMS data. All prepared compounds were screened for their in vitro protein tyrosine kinase (PTK) inhibitory activities. The effects of modification of the linker, functional groups and substituted positions at the phenyl ring on PTK inhibitory activity were investigated. Twelve halophenols showed significant PTK inhibitory activity. Among them, compounds 6c, 6d, 7d, 9d, 10d, 11d and 13d exhibited stronger activities than that of genistein, the positive reference compound. The results gave a relatively full and definite description of the structure-activity relationship and provided a foundation for further design and structure optimization of the halophenols. [ABSTRACT FROM AUTHOR]

Chemical examination of the fungus Aspergillus ustus isolated from the Mediterranean sponge Suberites domuncula yielded the five new ophiobolin-type sesterterpenoids - and the two new pyrrolidine alkaloids and , together with the known compound aurantiamine and cerebroside D. The structures of the new compounds were unambiguously elucidated on the basis of extensive spectroscopic-data analysis (1D- and 2D-NMR, MS, and UV) and comparison with literature data. All compounds were evaluated for their cytotoxicity against murine lymphoma cell line L5178Y. [ABSTRACT FROM AUTHOR]

Specimens of Suberites domuncula that had been cultured in aquaria for 4 weeks were analyzed for their associated fungi. A total of 81 fungal strains belonging to 20 different genera was isolated and identified by morphological and molecular methods. The most frequently isolated taxa were Cladosporium spp., Penicillium spp., Petriella sp., Phialophora spp. and Engyodontium album. Based on chromatographic and mass spectrometric analysis of fungal extracts, as well as on bioassay results, Aspergillus ustus, Penicillium sp., Petriella sp. and Scopulariopsis sp. were selected for in-depth analysis of their natural products. A total of 19 different fungal metabolites, including three new natural products, was isolated and structurally identified. A. ustus yielded two sesquiterpenes, a drimane derivative and deoxyuvidin, as well as a sesterterpene ophiobolin H. The drimane derivative had an ED50 value against L5178Y cells of 1.9 μg ml-1 in vitro. The crude extract of Petriella sp. was also strongly cytotoxic against the L5178Y cell line. The cyclic tetrapeptide WF-3161 was primarily responsible for the activity; the ED50 value was <0.1 μg ml-1. It was identical to the known compound WF-3161 and had been previously isolated from Petriella guttulata. In addition to WF-3161, three further natural products were obtained and unequivocally identified as new derivatives of infectopyrone by one- and two-dimensional NMR spectroscopy and by mass spectroscopy. Of the new compounds, only dihydroinfectopyrone was active against L5178Y cells; the ED50 value was 0.2 μg ml-1. Penicillium sp. yielded the largest number of metabolites. Viridicatin, viridicatol, cyclopenin and cyclopenol suppressed larval growth of the polyphagous pest insect Spodoptera littoralis when incorporated into an artificial diet at an arbitrarily chosen concentration of 237 ppm. Viridicatol was the most active compound and had an ED50 value of ca. 50 ppm. Scopulariopsis sp. yielded three metabolites, including the known acetylcholinesterase inhibitors quinolactacin A1 and A2. [ABSTRACT FROM AUTHOR]