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The molecule of the title compound, C14H19N3O7·0.5H2O, exhibits an E conformation about the C=N double bond. The water molecule possesses crystallographically imposed twofold symmetry. In the crystal structure, the molecules are connected by intermolecular O—H...O and N—H...O hydrogen bonds into a three-dimensional network.

The asymmetric unit of the title compound, C29H29ClO11, contains two independent molecules of similar geometry, both adopting an E conformation about the C=C double bond. The dihedral angles formed by benzene rings are 10.73 (16) and 13.79 (18)°. The pyranoside rings adopt a chair conformation. Intramolecular C—H...O close contacts occur. The crystal packing is stabilized by intermolecular C—H...O hydrogen bonds.

In the title compound, C18H18N2O3, the dihedral angle formed by the benzene rings is 71.75 (4)°. In the crystal structure, centrosymmetrically related molecules are linked into dimers by intermolecular O—H...O hydrogen bonds and π–π stacking interactions with centroid–centroid distances of 3.5511 (6) Å.

The title compound, C21H21BrO7·C2H6O, was synthesized by the Claisen–Schimidt reaction of helicid (systematic name: 4-formylphenyl-β-d-allopyranoside) with 4-bromoacetophenone in ethanol. The pyran ring adopts a chair conformation. In the crystal structure, molecules are linked into a three-dimensional network by intermolecular O—H...O hydrogen bonds.

The title compound, C21H24O11, crystallizes exclusively as the β-anomer. The substituent of the protected sugar at position C-3 is in the axial position, while all other groups are in equatorial positions. The pyranoside ring adopts a stable chair conformation.

The title compound, C22H27N3O10S, was synthesized by reaction of an ethanol solution of helicid (systematic name: 4-formylphenl-β-d-allopyranoside), thiosemicarbazide and acetic acid. The molecule exhibits a trans conformation with respect to the C=N double bond. The pyran ring adopts a chair conformation. In the crystal structure, the molecules are linked into chains parallel to the b axis by intermolecular N—H...O hydrogen bonds.

The title compound, C14H19NO6, was synthesized by the condensation reaction between hecilid (4-formylphenl-β-d-allopyranoside) and methylamine in methanol. In the crystal structure, the pyran ring adopts a chair conformation and adjacent molecules are linked by intermolecular O—H...O and O—H...N hydrogen bonds, forming a three-dimensional network.

The title compound, C34H54O5, was synthesized by the reaction of ursolic acid with ethyl chloroacetate in the presence of DMA. All six-membered rings of the pentacyclic triterpene skeleton adopt chair conformations. In the crystal structure, molecules are linked by intermolecular O—H...O hydrogen-bond interactions, forming zigzag chains along the c axis.