2-Amino­pyrimidinium dihydrogen phosphate monohydrate

In the title compound, C4H6N3 +·H2O4P−·H2O, the pyrimidin­ium ring is essentially planar, with an r.m.s. deviation of 0.0016 Å. In the structure, pairs of symmetry-related anions are connected into centrosymmetric clusters via strong O—H⋯O hydrogen bonds forming six-membered rings with an R 2 2(6) motif. These clusters are inter­connected via water mol­ecules through OW—H⋯O hydrogen bonds, building an infinite layer parallel to the ab plane. Moreover, infinite chains of 2-amino­pyrimidinium cations spread along the a-axis direction. These chains are connected to the inorganic layer through N—H⋯O, C—H⋯O and C—H⋯N hydrogen bonds, which, together with electrostatic and van der Waals inter­actions, contribute to the cohesion and stability of the network in the crystal structure

A Bulky Biaryl Phosphine Ligand Allows for Palladium-Catalyzed Amidation of Five-Membered Heterocycles as Electrophiles

The incredible bulk: The first palladium-catalyzed amidation of five-membered heterocyclic bromides with multiple heteroatoms was achieved using the Pd/1 catalyst system. N-Arylated imidazoles, pyrazoles, thiazoles, pyrroles, and thiophenes were synthesized in moderate to excellent yield. Experimental results and DFT calculations point to the need for an electron-rich and sterically demanding biaryl phosphine ligand to promote these difficult reactions.National Institutes of Health (U.S.) (Grant GM58160)National Science Foundation (U.S.) (Grant CHE9808061)National Science Foundation (U.S.) (Grant DBI 9729592)National Science Foundation (U.S.) (CHE-0946721

2-Amino­pyrimidinium picrate

The geometric parameters of the title compound, C4H6N3 +·C6H2N3O7 −, are in the usual ranges. While two nitro groups are almost coplanar with the aromatic picrate ring [dihedral angles 3.0 (2) and 4.4 (3)°], the third is significantly twisted out of this plane [dihedral angle 46.47 (8)°]. Anions and cations are connected via N—H⋯O hydrogen bonds. The mol­ecules crystallize in planes parallel to (11)

Antifungal Activity of Resveratrol Derivatives against Candida Species

trans-Resveratrol (1a) is a phytoalexin produced by plants in response to infections by pathogens. Its potential activity against clinically relevant opportunistic fungal pathogens has previously been poorly investigated. Evaluated herein are the candidacidal activities of oligomers (2a, 3–5) of 1a purified from Vitis vinifera grape canes and several analogues (1b–1j) of 1a obtained through semisynthesis using methylation and acetylation. Moreover, trans-ε-viniferin (2a), a dimer of 1a, was also subjected to methylation (2b) and acetylation (2c) under nonselective conditions. Neither the natural oligomers of 1a (2a, 3–5) nor the derivatives of 2a were active against Candida albicans SC5314. However, the dimethoxy resveratrol derivatives 1d and 1e exhibited antifungal activity against C. albicans with minimum inhibitory concentration (MIC) values of 29–37 μg/mL and against 11 other Candida species. Compound 1e inhibited the yeast-to-hyphae morphogenetic transition of C. albicans at 14 μg/mL

Chemical–Genetic Profiling of Imidazo[1,2-a]pyridines and -Pyrimidines Reveals Target Pathways Conserved between Yeast and Human Cells

Small molecules have been shown to be potent and selective probes to understand cell physiology. Here, we show that imidazo[1,2-a]pyridines and imidazo[1,2-a]pyrimidines compose a class of compounds that target essential, conserved cellular processes. Using validated chemogenomic assays in Saccharomyces cerevisiae, we discovered that two closely related compounds, an imidazo[1,2-a]pyridine and -pyrimidine that differ by a single atom, have distinctly different mechanisms of action in vivo. 2-phenyl-3-nitroso-imidazo[1,2-a]pyridine was toxic to yeast strains with defects in electron transport and mitochondrial functions and caused mitochondrial fragmentation, suggesting that compound 13 acts by disrupting mitochondria. By contrast, 2-phenyl-3-nitroso-imidazo[1,2-a]pyrimidine acted as a DNA poison, causing damage to the nuclear DNA and inducing mutagenesis. We compared compound 15 to known chemotherapeutics and found resistance required intact DNA repair pathways. Thus, subtle changes in the structure of imidazo-pyridines and -pyrimidines dramatically alter both the intracellular targeting of these compounds and their effects in vivo. Of particular interest, these different modes of action were evident in experiments on human cells, suggesting that chemical–genetic profiles obtained in yeast are recapitulated in cultured cells, indicating that our observations in yeast can: (1) be leveraged to determine mechanism of action in mammalian cells and (2) suggest novel structure–activity relationships

A two-step target binding and selectivity support vector machines approach for virtual screening of dopamine receptor subtype-selective ligands

10.1371/journal.pone.0039076PLoS ONE76