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Three new diterpenes, myrocin D (1), libertellenone E (2), and libertellenone F (3), and a new isocoumarin, decarboxyhydroxycitrinone (4), were isolated from the marine fungus Arthrinium sacchari, together with three known compounds (5-7). The structures of 1-4 were elucidated from spectroscopic data (NMR, MS, IR), and the absolute configurations of 1-3 were determined by X-ray diffraction analysis. The antiangiogenic activity of these compounds was evaluated by measuring their antiproliferation effects on human umbilical vein endothelial cells (HUVECs) and human umbilical artery endothelial cells (HUAECs). Compounds 4-7 showed inhibitory activity.

Four novel benzo[j]fluoranthene derivatives, hypoxylonols C (3), D (4), E (5), and F (6), have been isolated from the mushroom Hypoxylon truncatum, together with two known benzo[j]fluoranthene derivatives, hypoxylonols A (1) and B (2). The structures were established by analysis of NMR spectroscopic data and X-ray diffraction data. Compounds 4 and 5 showed antiproliferative activity against HUVECs (human umbilical vein endothelial cells) and HUAECs (human umbilical artery endothelial cells).

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The aims of this study were to investigate the role of tyrosine kinase in intracellular signaling and to search for lead compounds with tyrosine kinase inhibitory activity from metabolites of marine-derived fungi. We initially prepared 400 extracts from 200 species of marine fungi and then subjected them to a tyrosine kinase screening assay using human umbilical vein endothelial cell lysate. Tyrosine kinase inhibitory activity was observed among certain metabolites of Hypocrea vinosa. We isolated one known compound, SC2051 (1), as well as two new compounds, hypochromins A (2) and B (3), which have a bis(naphtho-gamma-pyrone) skeleton. Compounds 1-3 showed tyrosine kinase inhibitory activity, with IC(50) values of 42.1, 58.7, and 18.0 microMu, respectively. Furthermore, compounds 1-3 exhibited inhibitory effects on proliferation, migration, and tubule formation.

Two varieties of Zn-smectite were synthesized hydrothermally: sauconite, with an ideal composition of Na 0.4 Zn 3 (Si 3.6 Al 0.4 )O 10 (OH) 2 ·nH 2 O; and a Zn equivalent of hectorite, with an ideal composition of Na 0.4 (Li 0.4 Zn 2.6 )Si 4 O 10 (OH) 2 ·nH 2 O (referred to here as Zn-hectorite). For comparison, h y d r o t h e r m a l s y n t h e s i s o f t h e r e l a t e d t r i o c t a h e d r a l s m e c t i t e s o f h e c t o r i t e , Na 0.4 (Li 0.4 Mg 2.6 )Si 4 O l0 (OH) 2 ·nH 2 O and hectorites containing Cu, Co or Ni in the octahedral sheets instead of Mg were also attempted.The results showed that sauconite, Zn-hectorite and hectorite could be synthesized in the temperature range 100 1258C but hectorites containing Cu, Co or Ni in the octahedral sheet, under the same conditions or even at a temperature of 1508C, could not.

The three-dimensional structure of a flavoprotein, FP~,~o, from a luminescent bacterium, Photobacterium phosphoreum, solved by the molecular-replacement method, was refined to an R factor of 24.0% for 17433 independent reflections, from 6.0 to 2.7~, resolution, collected by synchrotron radiation. The asymmetric unit of the crystal (space group P4322, a=b=76.8 and c --242 A) contains two monomer molecules related by a non-crystallographic twofold axis to form a dimer. There are two Q-flavin [flavin mononucleotide (FMN) with myristic acid] molecules in FP3,~o monomer. One of them is located at the interface of dimer which is bound to both monomer and the another is at the molecular surface. The electron density of myristic acids of Qflavins at the dimer interface in both monomer are weak and unclear, showing the possibility that the Q-flavins bound in this site are not a single species but a mixture of two components, 6-(3"-myristic acid)-FMN and 6-(4"-myristic acid)-FMN.

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