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Vermistatin (=(3R)-4,6-dimethoxy-3-{4-oxo-6-[(1E)-prop-1-en-1-yl]-4H-pyran-3-yl}-2-benzofuran-1(3H)-one; 1) and two new vermistatin derivatives, compounds 2 and 3, were isolated from the fungal strain Guignardia sp. No. 4382 obtained from the South-China Sea. Their structures were elucidated by various methods, including circular dichroism (CD), 1D- and 2D-NMR, and HR-EI-MS. The structures of 1 and 2 were unequivocally corroborated by X-ray crystallography, and their absolute configurations were derived by CD spectroscopy based on a literature comparison. The in vitro cytotoxic and antifungal activities of 1 and 2 were tested.

Vermistatin (=(3R)-4,6-dimethoxy-3-{4-oxo-6-[(1E)-prop-1-en-1-yl]-4H-pyran-3-yl}-2-benzofuran-1(3H)-one; 1) and two new vermistatin derivatives, compounds 2 and 3, were isolated from the fungal strain Guignardia sp. No. 4382 obtained from the South-China Sea. Their structures were elucidated by various methods, including circular dichroism (CD), 1D- and 2D-NMR, and HR-EI-MS. The structures of 1 and 2 were unequivocally corroborated by X-ray crystallography, and their absolute configurations were derived by CD spectroscopy based on a literature comparison. The in vitro cytotoxic and antifungal activities of 1 and 2 were tested.

In the presence of guest 2,4'-bpy molecules or under acidic conditions, three compounds, [Cd(4,4'-bpy)(2)(H(2)O)(2)](ClO(4))(2).(2,4'-bpy)(2).H(2)O (1), [Zn(4,4'-bpy)(2)(H(2)O)(2)](ClO(4))(2).(2,4'-bpy)(2).H(2)O (2), and [Cu(4,4'-bpy)(2)(H(2)O)(2)](ClO(4))(4).(4,4'-H(2)bpy) (3), were obtained from the reactions of the metal salts and 4,4'-bpy in an EtOH-H(2)O mixture. 1 has a 2-D square-grid network structure, crystallizing in the monoclinic space group P2/n, with a = 13.231(3) Å, b = 11.669(2) Å, c = 15.019(3) Å, beta = 112.82(3) degrees, Z = 2; 2 is isomorphous with 1, crystallizing in the monoclinic space group P2/n, with a = 13.150(3) Å, b = 11.368(2) Å, c = 14.745(3) Å, beta = 110.60(3) degrees, Z = 2. The square grids superpose on each other into a channel structure, in which each layer consists of two pairs of shared edges, perfectly square-planar with an M(II) ion and a 4,4'-bpy at each corner and side, respectively. The square cavity has dimensions of 11.669(2) x 11.788(2) and 11.368(2) x 11.488(2) Å for 1 and 2, respectively. Every two guest 2,4'-bpy molecules are clathrated in each hydrophobic host cavity and are further stabilized by pi-pi stacking and hydrogen bonding interactions. The NMR spectra clearly confirm that both 1 and 2 contain 4,4'-bpy and 2,4'-bpy molecules in a 1:1 ratio, which have stacking interaction with each other in the solution. 3 crystallizes in the orthorhombic space group Ibam, with a = 11.1283(5) Å, b = 15.5927(8) Å, c = 22.3178(11) Å, Z = 4. 3 is made up of two-dimensional square [Cu(4)(4,4'-bpy)(4)] grids, where the square cavity has dimensions of 11.13 x 11.16 Å. Each [4,4'-H(2)bpy](2+) cation is clathrated in a square cavity and stacks with one pair of opposite edges of the host square cavity in an offset fashion with the face-to-face distance of ca. 3.95 Å. Within each cavity, the [4,4'-H(2)bpy](2+) cation forms twin three-center hydrogen bonds with two pairs of ClO(4)(-) anions. The results suggest that the guest 2,4'-bpy molecules and protonated [4,4'-H(2)bpy](2+) cations present in the reaction systems serve as structure-directing templates in the formation of the crystal structures and exclude self-inclusion of the networks having larger square cavities.

The title compound, C9H10Br2N2O3, was synthesized by chloro­form reaction of glycine methyl ester with 4,5-di­bromo-1-methyl-2-(tri­chloro­acetyl)­pyrrole at room temperature and was obtained in 74.6% yield. The crystal structure was determined by X-ray diffraction.