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In the title chalcone derivative, C16H16O5, the dihedral angle between the furan and benzene rings is 2.06 (17)°. The two methoxy groups at the ortho and para positions are essentially coplanar with the benzene ring [C—O—C—C angles = −1.0 (5) and 178.5 (3)°], whereas the third one at the meta position is slightly twisted [C—O—C—C = 9.6 (5)°]. In the crystal, weak C—H
O interactions link the molecules into a sheet parallel to (
02). An intermolecular π–π interaction between the furan and benzene rings is present [centroid–centroid distance = 3.772 (2) Å]. A short CC contact [3.173 (5) Å] is also observed between neighbouring furan rings.
O interactions link the molecules into a sheet parallel to (
02). An intermolecular π–π interaction between the furan and benzene rings is present [centroid–centroid distance = 3.772 (2) Å]. A short CC contact [3.173 (5) Å] is also observed between neighbouring furan rings.organic compoundsOpen access
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The title compound {systematic name: (S)-1-[(2S,4aR,8aR)-2,4b,8,8-tetramethyl-2,3,4,4a,4b,5,6,7,8,8a,9,10-dodecahydrophenanthren-2-yl]ethane-1,2-diol}, C20H34O2, is an ent-pimarane diterpenoid which was isolated from the stem bark of Ceriops tagal. In the asymmetric unit, there are two crystallographically independent molecules, which are conformationally almost identical. In each molecule, the two cyclohexane rings of the fused three-ring system adopt chair conformations, while the cyclohexene ring is in an envelope conformation, with the methylene C atom next to the side chain as the flap atom. In the crystal, molecules are stacked in columns along the b axis through O—HO hydrogen bonds.
O hydrogen bonds.organic compoundsOpen access
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There are two crystallographically independent molecules in the asymmetric unit of the title compound, C14H11ClN4O4, with the same E conformation about the C=N double bond. The molecules are approximately planar, with a dihedral angle between the benzene rings of 10.24 (12)° in one molecule and 4.73 (12)° in the other. In both molecules, the ortho-nitro groups of the 2,4-dinitrophenyl units are coplanar to their bound benzene rings, whereas the para-nitro groups are slightly twisted. In each molecule, intramolecular N—HO hydrogen bonds generate S(6) ring motifs. In the crystal, molecules are linked by weak C—HO interactions into sheets parallel to the (-102) plane. These sheets are stacked by π–π interactions, with centroid–centroid distances of 3.7008 (14) and 3.7459 (14) Å. A ClO short contact [3.111 (2) Å] is observed.
O hydrogen bonds generate S(6) ring motifs. In the crystal, molecules are linked by weak C—HO interactions into sheets parallel to the (-102) plane. These sheets are stacked by π–π interactions, with centroid–centroid distances of 3.7008 (14) and 3.7459 (14) Å. A ClO short contact [3.111 (2) Å] is observed.organic compoundsOpen access
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In the molecule of the title benzohydrazide derivative, C17H18N2O4, the dihedral angle between the two benzene rings is 6.86 (11)°. The methoxy group of the 4-methoxyphenyl fragment deviates slightly [Cmethyl—O—C—C = 10.0 (4)°] with respect to the benzene ring, whereas the ethoxy group of the 3-ethoxy-4-hydroxyphenyl fragment is almost coplanar [C—O—C—Cmethyl = 178.5 (2)°]. In the crystal, molecules are linked by N—HO, O—HO and C—HO hydrogen bonds into a two-dimensional network parallel to the ab plane. C—Hπ interactions and CO [2.980 (3) Å] short contacts are also observed.
O, O—HO and C—HO hydrogen bonds into a two-dimensional network parallel to the ab plane. C—Hπ interactions and CO [2.980 (3) Å] short contacts are also observed.organic compoundsOpen access
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The benzohydrazide molecule of the title compound, C16H16N2O3·2H2O, exists in a trans conformation with respect to the C=N double bond. The central O=C—NH—N=C plane [r.m.s. deviation of 0.0165 (1) Å for the five non-H atoms] makes dihedral angles of 6.04 (8) and 2.38 (8)°, respectively, with the hydroxy- and ethoxy-substituted benzene rings. The dihedral angle between these benzene rings is 3.82 (7)°. The ethoxy group is almost coplanar with the attached benzene ring with a C—O—C—C torsion angle of −176.58 (11)°. In the crystal, the benzohydrazide and water molecules are linked by N—HO, O—HO , O—HN and C—HO hydrogen bonds into a three-dimensional network.
O, O—HO , O—HN and C—HO hydrogen bonds into a three-dimensional network.
