In the title compound, C(9)H(15)N(3)O(4), the 1,3-dioxane ring displays a chair conformation and the five-membered ring is close to planar (r.m.s. deviation = 0.054 Å). An intra-molecular N-H⋯O hydrogen bond to one of the nitro-group O atoms generates an S(6) ring. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into C(6) chains propagating in [010] and a C-H⋯O link als...

In the title hydrate, C(10)H(10)O(4)·H(2)O, the six-membered aliphatic ring that is fused to the benzene ring has a sofa shape, with the hy-droxy group in the 3-position (that represents the sofa back) of the aliphatic ring occupying a quasi-axial position. The hy-droxy group of the aromatic ring is hydrogen-bond donor to the carbonyl O atom; other O-H⋯O hydrogen bonds link the organic mol-ecul...

In the asymmetric unit of the title compound, C(16)H(11)FO(5)S, the 2H-chromene ring is essentially planar, with a maximum deviation of 0.040 (2) Å. The dihedral angle between the 2H-chromene ring and the 4-fluoro-phenyl ring is 2.17 (8)°. One of the sulfonamide O atoms is approximately coplanar with the benzene ring [C-C-S-O torsion angle = 166.00 (14)°], whereas the other O atom lies well bel...

In the title compound, C(30)H(32)N(2)O(7)·CH(4)O, the tetra-hydro-furan ring and the six-membered ring fused to it both display envelope conformations, with the ring C atom opposite the carbonyl group and the adjacent bridgehead C atom as the flaps, respectively. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link all moieties into ribbons along [010]. Weak inter-molecular C-H⋯O...

In the title compound, C21H21BrClNO4, the dihydro-pyridine ring adopts a flattened boat conformation. The 3-bromo-5-chloro-2-hy-droxy-phenyl ring forms a dihedral angles of 84.44 (7)° with the dihydro-pyridine mean plane. The mol-ecular conformation is stabilized by an intra-molecular O-H⋯O hydrogen bond, with an S(8) ring motif. In the crystal, O-H⋯O and C-H⋯O hydrogen bonds link the mol-ecule...

In the title compound, C(18)H(14)N(2)O(4), the dihedral angle between the benzene ring and the naphthyl ring system is 10.1 (2)°. The mol-ecule is nearly planar, with a mean deviation from the plane of 0.141 (2) Å for 24 non-H atoms. An intra-molecular O-H⋯N hydrogen bond forms a pseudo-6-membered ring and the mol-ecules are linked into sheets by inter-molecular N-H⋯O and O-H⋯O hydrogen bonds.

in this note we introduce the notion of weak mccoy rings as a generalization of mccoy rings, and investigate their properties. also we show that, if is a semi-commutative ring, then is weak mccoy if and only if is weak mccoy.

The title penta-cyclic oxindole alkadoid, isolated from Uncaria longiflora, crystallizes as a methanol solvate, C(20)H(22)N(2)O(4)·CH(4)O. The five-membered ring comprising the indole fused ring is nearly planar [maximum atomic deviation = 0.031 (2) Å], whereas the five-membered ring having alphatic C atoms adopts an envelope shape (with the tertiary N atom representing the flap). The six-membe...

The asymmetric unit of the title compound, C(12)H(12)O(6), contains two essentially identical mol-ecules related by a pseudo-inversion centre. The three acet-oxy groups in each mol-ecule are essentially planar and are tilted, in a regular propeller-style arrangement, with their normals oriented between 56.72 (12) and 76.35 (9)° from the normal to the mean plane of the central C(6) ring; in each...

The title compound, C19H20N4O3S, was synthesized by refluxing equimolar amounts of 1-phenyl-3-methyl-4-propionylpyrazol-5-one and benzene-sulfonyl hydrazide in ethanol. The compound crystallizes in the keto form and the carbonyl O atom forms an intra-molecular N-H⋯O hydrogen bond with the neighbouring NH group. There is also C-H⋯O short contact involving the neighbouring phenyl ring. Probably a...