Second monoclinic modification of cyclo­hexane-1,1-dicarbonitrile

In the title compound, C8H10N2, the cyclo­hexane ring adopts a chair conformation. he crystal structure of the previously reported monoclinic modification have intramolecular CN⋯CN and C—H⋯N interactions. These types of interaction are not present in this new modification whose crystal structure is built up by van der Waals interactions

Dimethyl 11,13-dimethyl-16-[1,2-bis­(methoxy­carbon­yl)ethen­yl]-12-oxo-16,17-dioxa-18-aza­hexa­cyclo­[7.5.1.11,4.16,9.110,14.05,15]octa­deca-2,7-diene-2,3-dicarboxyl­ate

The title compound, C27H29NO11, is a product of the tandem ‘domino’ Diels–Alder reaction. The mol­ecule comprises a fused hexa­cyclic system containing four five-membered rings (two dihydro­furan and two tetra­hydro­furan) in the usual envelope conformations and two six-membered rings (tetra­hydro­pyridinone and piperidine) adopting slightly flattened boat and chair conformations, respectively. The dispositions of the carboxyl­ate substituents relative to each other are determined by both steric reasons and inter­molecular C—H⋯O hydrogen bonding and attractive anti­parallel C=O⋯C=O inter­actions [C⋯O = 2.995 (2) Å]

Methyl 4,5-diacet­oxy-1-oxo-2-phenyl­perhydro-4,6-epoxy­cyclo­penta­[c]pyridine-7-carboxyl­ate ethanol solvate

The title compound, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as an ethanol monosolvate, C20H21NO8·C2H6O. The title mol­ecule comprises a fused tricyclic system containing two five-membered rings (cyclo­pentane and tetra­hydro­furan) in the usual envelope conformations and one six-membered ring (piperidinone) adopting a flattened twist–boat conformation

N-tert-Butyl-3-mesitylpropanamide

In the title compound, C16H25NO, the N-tert-butyl­propanamide fragment is essentially planar, with the exception of two C atoms of the tert-butyl group (r.m.s. deviation = 0.005 Å), forming a dihedral angle of 84.09 (10)° with the plane of the mesityl fragment (r.m.s. deviation = 0.002 Å). The crystal packing is stabilized by an inter­molecular N—H⋯O hydrogen bond, which links the mol­ecules into chains with graph-set notation C(4) running parallel to the c axis

1-(6-Methyl-3-phenyl-2-sulfanyl­idene-1,2,3,4-tetra­hydro­pyrimidin-5-yl)ethanone

In the title compound, C13H14N2OS, four C atoms of the phenyl ring are disordered over two sets of sites in a 0.60 (3):0.40 (3) ratio. The heterocyclic ring is essentially planar (r.m.s. deviation = 0.017 Å) and forms dihedral angles of 82.0 (2) and 79.3 (3)°, respectively, with the major and minor occupancy components of the phenyl ring. The crystal packing features N—H⋯O hydrogen bonds, which link the mol­ecules into C(6) chains running parallel to the b axis

Methyl 7,8-diacet­oxy-11-oxo-5-(2-oxo­pyrrolidin-1-yl)-7,9-epoxy­cyclo­penta­[4,5]pyrido[1,2-a]quinoline-10-carboxyl­ate sesquihydrate

The title compound, C26H28N2O9·1.5H2O, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as a sesquihydrate with the O atom of one of the two independent water mol­ecules occupying a special position on a twofold axis. The organic mol­ecule comprises a fused penta­cyclic system containing two five-membered rings (cyclo­pentane and tetra­hydro­furan) and three six-membered rings (piperidinone, tetra­hydro­pyridine and benzene). The five-membered rings have the usual envelope conformations, and the central six-membered piperidinone and tetra­hydro­pyridine rings adopt boat and sofa conformations, respectively. In the crystal, there are three independent O—H⋯O hydrogen bonds, which link the organic mol­ecules and water mol­ecules into complex two-tier layers parallel to (001). The layers are further linked into a three-dimensional framework by attractive inter­molecular carbon­yl–carbonyl inter­actions

Ethyl (Z)-2-(4-chloro­benzyl­idene)-3-oxobutano­ate

The C=C double-bond in the title compound, C13H13ClO3, has a Z configuration. The aliphatic substituents at one end of the double bond, i.e. the CH3CO– and C2H5O2C– groups, are aligned at 82.1 (3)° with respect to each other

Molecular and crystalline architectures based on HgI : from metallamacrocycles to coordination polymers

We report the synthesis and X-ray characterization of three metallamacrocycles and one coordination polymer obtained by using coordination driven self-assembly of the HgI2 salt with four different ligands

3-[2-Hy­droxy-3-(2,4,6-trimethyl­phen­yl)prop­yl]-3-methyl-1-phenyl­thio­urea

In the title compound, C20H26N2OS, four non-H atoms of the thio­urea unit are approximately planar (r.m.s. deviation = 0.005 Å); the phenyl and benzene rings are twisted out of this plane by 28.55 (7) and 60.00 (7)°, respectively. An intra­molecular N—H⋯O hydrogen bond occurs. The hy­droxy group is hydrogen bonded to the double-bond S atom of an inversion-related mol­ecule, generating a hydrogen-bonded dimer in the crystal structure

9-(5-Bromo-2-hy­droxy­phen­yl)-10-(2-hy­droxy­prop­yl)-3,3,6,6-tetra­methyl-1,2,3,4,5,6,7,8,9,10-deca­hydro­acridine-1,8-dione

The dihydro­pyridine ring in the title compound, C26H32BrNO4, adopts an envelope conformation with the methine C atom representing the flap. The cyclo­hexenone rings also adopt envelope conformations. The phenolic hy­droxy group forms an intra­molecular hydrogen bond to one of the two keto O atoms. Inter­molecular weak C—H⋯O hydrogen bonding is present in the crystal structure. The hy­droxy­propyl group is disordered over two sets of sites with an occupancy ratio of 0.636 (6):0.364 (6)