Two new peptides, stylissamides G and H, were isolated from extracts of a sample of Stylissa caribica collected in deep waters of the Caribbean Sea. A single sample of S. caribica among a collection of 10 samples that were examined by LC-MS appeared to be a different chemotype from the others in that it lacked the familiar pyrrole-2-aminoimidazole alkaloids, stevensine and oroidin, and containe...

The title nitro-pyrrole-based compounds, C7H8N2O4, (I) (ethyl 4-nitro-1H-pyrrole-2-carboxyl-ate), its derivative C12H14N2O4, (II) [ethyl 4-nitro-1-(4-pent-yn-yl)-1H-pyrrole-2-carboxyl-ate], C15H26N4O3, (III) {N-[3-(di-methyamino)prop-yl]-1-isopentyl-4-nitro-1H-pyrrole-2-carboxamide}, and C20H27N9O5, (IV) {1-(3-azido-prop-yl)-4-(1-methyl-4-nitro-1H-pyrrole-2-carboxamido)-N-[2-(morpholin-4-yl)eth...

In the frame of a systematic study on sequestering ability natural antioxidants towards metal cations, complexation coumarin-3-carboxilic acid (HCCA) with neodymium(III) and dioxouranium(VI) (uranyl, UO22+), overall stability constants resulting complexes, were evaluated from pH-potentiometric titration data at 37 °C in an aqueous solution (i.e., 0.16 mol/L NaClO4). The graphic representation c...

The title compound, C(5)H(7)N(3)O, was obtained by the reaction of ethyl 1H-pyrrol-2-carboxyl-ate and hydrazide hydrate. In the crystal, mol-ecules are linked via inter-molecular N-H⋯N and N-H⋯O hydrogen bonds, forming a supra-molecular grid.

Organocatalyzed synthesis of tert-butyl 2-amino-3-cyano-5-oxo-4-phenyl-5,7-dihydropyrano[2,3-c]pyrrole-6(4H)-carboxylate, prepared from Boc-tetramic acid and benzylidenemalononitrile, is disclosed. Two bifunctional noncovalent organocatalysts were employed, yielding the product as a racemic mixture in both cases. The structure new synthesized compound was confirmed by high resolution mass-spect...

Carboxhydrazides 3 were synthesized by reaction of substituted furo[3,2-b]pyrrole-5-carboxhydrazides 1 with 4-oxo-4H-chromene-2-carboxaldehyde 2 in the presence of 3-methyl-benzenesulfonic acid in ethanol. Carboxhydrazides 3 were used as ligands for synthesis of Cu, Co, and Ni complexes 4.

Previous studies have established that 4-hydroxy-2-nonenal is a lipid hydroperoxide-derived aldehydic bifunctional electrophile that reacts with DNA and proteins. However, it has now been recognized that 4-oxo-2-nonenal is also a major product of lipid hydroperoxide decomposition. Furthermore, 4-oxo-2-nonenal is more reactive than 4-hydroxy-2-nonenal toward the DNA-bases 2'-deoxyguanosine, 2'-d...

The structures of pyrrolic forms of cross-links in collagen have been confirmed by reacting collagen peptides with a biotinylated Ehrlich's reagent. This reagent was synthesized by converting the cyano group of N-methyl-N-cyanoethyl-4-aminobenzaldehyde to a carboxylic acid, followed by conjugation with biotin pentyl-amine. Derivatization of peptides from bone collagen both stabilized the pyrrol...

In the crystal structure of the title compound, C(9)H(14)BNO(4), the boronic acid group and carbamate groups are nearly co-planar with the pyrrole ring, making dihedral angles of 0.1 (2) and 2.2 (2)°, respectively. Intra-molecular and inter-molecular O-H⋯O hydrogen bonds help to stabilize the structure, the latter interaction leading to inversion dimers..