Crystal structure of a new organic hydrogenmonophosphate adduct [2-NH2-6-CH3-C4H3N2O]2HPO4

Crystal structure of bis-(2-amino-anilinium) hydrogen phosphate

The asymmetric unit of the title compound, 2C6H9N2 (+)·HPO4 (2-), comprises two 2-amino-anilinium cations and one hydrogen phosphate dianion. In the crystal, the HPO4 (2-) dianions are linked by O-H⋯O hydrogen bonds into chains along [100]. The inorganic anionic chains and organic cations are linked by N-H⋯O and N-H⋯N hydrogen bonds, forming a two-dimensional supra-molecular network extending parallel to (001).

N (2)-(4-Meth-oxy-salicyl-idene)arginine hemihydrate

The title compound, C₁₄H₂₀N₄O₄·0.5H₂O [systematic name: (2S)-5-{[amino­(iminium­yl)meth­yl]amino}-2-{[(1Z)-4-meth­oxy-2-oxido­benzyl­idene]aza­nium­yl}penta­noate hemihydrate], has been synthesized by the reaction of l-arginine and 4-meth­oxy­salicyl­aldehyde and crystallizes with two independent substituted l-arginine mol­ecules and one water mol­ecule of solvation in the asymmetric unit. Each mol­ecule exists as a zwitterion and adopts a Z configuration about the central C=N. The mol­ecular conformation is stabilized by strong intra­molecular N—H⋯O hydrogen bonds that generate S(6) and S(10) ring motifs. Inter­molecular N—H⋯O and O—H⋯O hydrogen bonds involving also the water mol­ecule and weak inter­molecular C—H⋯O_water inter­actions link the mol­ecules into an infinite one-dimensional ribbon structure extending along the b axis. The known (2S) absolute configuration for l-arginine was invoked. Weak intermolecular C—H⋯π interactions are also present.

2-Amino-4-methyl-6-oxo-3,6-dihydro-pyrimidin-1-ium perchlorate-2-amino-6-methyl-pyrimidin-4(1H)-one-water (1/1/1)

In the title compound, C(5)H(8)N(3)O(+)·ClO(4) (-)·C(5)H(7)N(3)O·H(2)O, each perchlorate anion is paired with a protonated cationic 2-amino-6-methyl-pyrimidin-4(1H)-one and another non-protonated entity of the same organic pyrimidinone. The crystal structure is stabilized by N-H⋯O(org), N-H⋯O(water), N-H⋯O(ClO4), O-H⋯O(ClO4), N-H⋯N and C-H⋯O(ClO4) hydrogen bonds between the anions, organic entities and water mol-ecules. Inter-molecular π-π stacking inter-actions between neighbouring organic rings are observed with a face-to-face distance of 3.776 (2) Å, and O-H⋯O hydrogen bonds link the perchlorate anions and the water mol-ecules into chains along the b-axis direction. The perchlorate anion and the inter-stitial water mol-ecule are disordered over two mutually incompatible positions with a common occupancy ratio of 0.678 (16):0.322 (16).