organic compounds
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In the crystal structure of the title compound, C4H13N52+·2NO3−, the main intermolecular interactions are the N—HO hydrogen bonds between the cationic amino groups and the O atoms of the nitrate ions. All amino H atoms and nitrate O atoms are involved in the three-dimensional hydrogen-bond network. There are two graph-set motifs R22(8), which include the amino groups connected to the N atoms in the biguanide 3-, 4- and 5-positions, and the O atoms of a nitrate ion. They are extended along the a axis. An O atom of the second nitrate ion is involved in a graph-set motif C(4) that is a part of a helix-like N—HOH—N—HO chain oriented along the b axis. There are also two weak C—HO interactions in the crystal structure.
organic compounds
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In the title compound, C90H120O18·2CH3CN, the calix[6]arene has a 1,2,3-alternate conformation and possesses inversion symmetry. It crystallizes as an acetonitrile disolvate, with a half-molecule of calix[6]arene and one molecule of solvent in the asymmetric unit. In the crystal, the two solvent molecules are enclosed in voids between the calix[6]arene molecules. They form weak C—HO hydrogen bonds involving an O atom of the lower rim substituent. The cavity of the calix[6]arene itself is enclosed by two opposite phenol rings, which are turned into the cavity due to the presence of a C—Hπ interaction. The calix[6]arene molecule exhibits disorder of one substituent on its lower rim [occupancy ratio 0.897 (3):0.103 (3)].
organic compounds
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In the crystal of the title compound, C7H7NO3, molecules associate into infinite chains via O—HO(NO2) hydrogen bonds propagating in the [101] direction. These chains are linked via C—HO(NO2) hydrogen bonds to form double-stranded ribbons lying parallel to the ac plane. The ribbons stack along the b axis by means of π–π interactions involving the benzene rings and the nitro group. The centroid–centroid distances of the alternating parallel aromatic rings are 3.6514 (7) and 3.8044 (7) Å.