ABSTRACT: In the title compound, C22H24N2O6, the indole ring has a twist conformation and the tetra-hydro-2H-pyran-2-one ring a half-chair conformation. One of the pyrrolidine rings adopts an envelope conformation on the N atom, while the other has a twist conformation; the 'butterfly' angle between their mean planes is 62.98?(11)°. The dioxolane ring adopts a twist conformation and the tetra-hydro-furan ring has an envelope conformation on the C atom in the fused tetra-hydro-2H-pyran-2-one ring adjacent to the O atom of the tetra-hydro-furan ring. The 'butterfly' angle between the mean planes of these two five-membered rings is 69.14?(10)°. In the crystal, mol-ecules are linked by N-H?O hydrogen bonds, forming chains along the a axis.
Project description:In the title compound, C14H13ClN2O5S, the chlorine-substituted tetrahydrofuran ring adopts a twist conformation and the other tetra-hydro-furan ring an envelope conformation with the O atom as the flap. The pyrrolidine ring adopts a twist conformation. In the crystal, C-H?O hydrogen bonds link the mol-ecules into zigzag chains running along the b-axis direction.
Project description:In the title compound, C27H24N2O3, the dihedral angle between the mean planes of the di-hydro-furan and 3,4-di-hydro-quinoline ring systems is 70.65?(9)°. The di-hydro-furan ring adopts an envelope conformation with the C atom adjacent to the methyl-ene C atom of the pyrrolidine ring as the flap. The five-membered pyrrolidine ring adopts a twist conformation on the N-C(tetra-substituted) bond. In the crystal, mol-ecules are linked via pairs of N-H?O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. The dimers are linked via pairs of C-H?O hydrogen bonds, forming ribbons enclosing R 2 (2)(12) ring motifs lying in a plane parallel to (01-1).
Project description:In the title compound, C30H29BrN2O5, the ?-lactam ring is essentially planar, with the O atom displaced from this plane by 0.856?(9)?Å, and forming dihedral angles of 24.35?(13) and 89.42?(14)° with the planes of the benzene substituent groups on this ring. The tetra-hydro-pyran ring adopts an envelope conformation with the C atom bearing the ?-lactam ring as the flap. In the crystal, weak C-H?O hydrogen bonds with carboxyl and tetra-hydro-pyran O-atom acceptors give rise to a chain structure extending along the b-axis direction.
Project description:The title compound, C(16)H(17)NOS(2), consists of a carbazole skeleton with tetra-hydro-furan and dithiol-ane rings. In the indole ring system, the benzene and pyrrole rings are nearly coplanar, forming a dihedral angle of 1.57?(15)°. The cyclo-hexenone and tetra-hydro-furan rings have envelope conformations, while the dithiol-ane ring adopts a twist conformation. In the crystal structure, pairs of weak inter-molecular N-H?S hydrogen bonds link the mol-ecules into centrosymmetric dimers with R(2) (2)(16) ring motifs. Weak C-H?? inter-actions may further stabilize the structure.
Project description:The title compound, C15H19NO4, is the a product of the esterification of the corresponding carbonic acid with methanol. The mol-ecule comprises a fused tetra-cyclic system containing three five-membered rings (2-pyrrolidinone, tetra-hydro-furan and di-hydro-furan) and one seven-membered ring (azepane). The five-membered rings have the usual envelope conformations, with the quaternary C atom being the flap atom for the 2-pyrrolidinone ring, and the ether O atom being the common flap atom for the remaining rings. The seven-membered azepane ring adopts a chair conformation with the methine and middle methyl-ene C atoms lying above and below the mean plane defined by the remaining five atoms. The carboxyl-ate substituent is rotated by 77.56?(5)° with respect to the base plane of the tetra-hydro-furan ring. In the crystal, the mol-ecules are bound by weak C-H?O hydrogen-bonding inter-actions into puckered layers parallel to (001).
Project description:In the title compound, C(35)H(30)N(2)O(5)Se, the pyrrolidine ring adopts an envelope conformation and the oxazolidine ring is in a twist conformation. The tetra-hydro-pyran ring adopts a half-chair conformation. The methoxy-phenyl ring is twisted away from the attached azetidinone ring by 15.7?(1)°. In the crystal structure, inter-molecular C-H?O inter-actions link the mol-ecules into a two-dimensional network.
Project description:In the title compound, C(27)H(27)NO(3), the pyrrolidine ring exhibits a twist conformation and the piperidine ring exhibits a chair conformation. The pyrrolidine ring makes dihedral angles of 54.47?(5), 51.50?(5) and 73.37?(6)° with the napthalene ring system and the tetra-hydro-pyran and phenyl rings, respectively. The structure is stabilized by intra-molecular C-H?O and C-H?N inter-actions.
Project description:In the title compound, C14H14O4, the dihedral angle between the hydro-furan and benzene rings is 88.41?(15)°. The hydro-pyran ring adopts an envelope conformation, with the O-bound methyl-ene C atom as the flap. In the crystal, weak aromatic ?-? stacking is observed [centroid-centroid separation = 3.848?(2)?Å].
Project description:Tthe structure of the title compound, C(15)H(24)O(5), has been redetermined at 103?(2)?K, with much improved precision. The title compound was first reported by Luo, Yeh, Brossi, Flippen-Anderson & Gillardi [Helv. Chim. Acta (1984). 67, 1515-1522]. It is a derivative of the anti-malaria compound artemisinin and consists primarily of three substituted ring systems fused together. A cyclo-hexane ring (with a distorted chair conformation), is fused to a tetra-hydro-pyran group (also with a distorted chair conformation), and is adjacent to an oxacyclo-heptane unit containing an endoperoxide bridge. This gives the mol-ecule a unique three-dimensional arrangement. The crystal packing is stabilized by inter-molecular C-H?O and O-H?O inter-actions between an H atom from the cyclo-hexane ring and an O atom from the endoperoxide bridge, as well as between the hydroxyl H atom and an O atom from a tetra-hydro-pyran ring.
Project description:The title compound, C20H18O6, prepared from d-mannitol by a two-step procedure, is a functionalized fused bis-tetra-hydro-furan. In the central fragment, consisting of two fused tetra-hydro-furan rings, one O atom and its two adjacent C atoms, a methyl-ene and a bridgehead C atom, are disordered over two sets of sites with an occupancy ratio of 0.735?(9):0.265?(9). In the major component, the ring containing the disordered O atom is a half-chair conformation with twisted methylene and benzoate-substituted C atoms, whereas the other ring has a half-chair or T-form conformation. In the minor component, the ring with the disordered O atom has an envelope conformation, with the O atom as the flap, and the other ring has a half-chair conformation, with the O atom and the other bridgehead CH atom being twisted. The two aromatic rings are inclined to one another by 20.00?(12)°. In the crystal, adjacent molecules are linked via C-H?? interactions, forming chains propagating along .