D. Sudha

3-Ethyl-9-phenyl-2-tosyl-2,3,3a,4,9,9a-hexahydro-1H-pyrrolo[3,4-b]quinoline

In the molecule of the title compound, C26H28N2O2S, the pyrrolidine ring adopts an envelope conformation and the tetrahydropyridine ring is in a half-chair conformation; these two rings are trans-fused. The dihedral angle between the pyridine- and sulfonyl-bound benzene rings is 36.15 (5)°. In the crystalline state, the molecules are linked into a two-dimensional network parallel to the ab plane by C—H⋯O and C—H⋯π interactions.

cis-1-Ethyl-4,4,6,8-tetra­methyl-2-tosyl-2,3,3a,4,6,7,8,9-octa­hydro-1H-pyrrolo[3′,4′:3,4]pyrano[6,5-d]pyrimidine-7,9-dione

In the title compound, C22H29N3O5S, the pyrrolidine ring is cis-fused to the dihydropyran ring. The pyrrolidine and dihydropyran rings adopt twist and half-chair conformations, respectively. The molecule is in a folded conformation; the sulfonyl-bound benzene ring lies over the pyrimidinedione ring, with a weak π–π interaction [centroid–centroid distance = 3.6147 (4) Å]. A weak intramolecular C—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked into a three-dimensional network by C—H⋯O hydrogen bonds.

1-Benzyl-6,8-dimethyl-4-phenyl-2-tosyl-1,2,3,3a,4,6,7,8,9,9b-deca-hydro-pyrrolo[3,4-c]pyrano[6,5-d]pyrimidine-7,9-dione.

The molecule of the title compound, C31H31N3O5S, adopts a folded conformation, with the sulfonyl-bound phenyl ring lying over the pyrimidine ring [dihedral angle = 12.04 (6)° and centroid–centroid separation = 3.6986 (8) Å]. The pyrrolidine ring adopts a twist conformation, the dihydropyran ring is in a half-chair conformation and the two rings are cis-fused. The tosyl group is attached to the pyrrolidine ring in an equatorial position while the benzyl group is axially attached. The molecular structure is stabilized by weak C—H⋯O hydrogen bonds and C—H⋯π interactions. In the crystal, pairs of molecules related by inversion symmetry are linked by C—H⋯O hydrogen bonds, forming chains propagating along the c axis which are cross-linked into a three-dimensional framework by further C—H⋯O links.

4,4-Dimethyl-2-tosyl-1,2,3,3a,4,11b-hexa-hydro-11H-pyrrolo[3,4-c]pyrano[5,6-c]chromen-11-one 0.125-hydrate.

In the title compound, C23H23NO5S·0.125H2O, the pyrrolidine ring has a twist conformation and the dihydropyran ring adopts a half-chair conformation; the two rings are cis-fused. The molecule adopts a folded conformation. The sulfonyl-bound phenyl ring and the pyran ring of the coumarin ring system are stacked over one another, with a centroid–centroid distance of 3.7470 (7) Å; the dihedral angle between the two rings is 18.93 (2)°. An intramolecular C—H⋯O hydrogen bond is observed. The solvent water molecule, lying on a twofold rotation axis, is only partially occupied with an occupancy of 0.125 (relative occupancy with respect to the main molecule) and is involved in O—H⋯O and C—H⋯O hydrogen bonding.

7-Bromo-3-ethyl-9-phenyl-2-tosyl-pyrrolo[3,4-b]quinoline.

In the title compound, C26H27BrN2O2S, the pyrrolidine ring adopts a twist conformation, while the tetrahydropyridine ring is in a half-chair conformation. The two rings are trans-fused. The dihedral angle between the phenyl ring and the sulfonyl-bound benzene ring is 22.83 (7)°. N—H⋯O hydrogen bonds link the molecules into a chain along the b axis, and the chains are cross-linked into a three-dimensional network by a C—H⋯π interaction and a weak π-π interaction between the sulfonyl-bound benzene rings; the centroid–centroid distance is 3.6957 (8) Å.

1-Ethyl-2-tosyl-4,4,6-trimethyl-2,3,3a,4-tetra-hydro-1H-pyrrolo[3,4-c]pyrano[6,5-b]quinoline-11(6H)-one monohydrate.

In the title compound, C26H30N2O4S·H2O, the pyrrolidine and dihydropyran rings adopt envelope conformations and they are cis-fused. The sulfonyl group has a distorted tetrahedral geometry. In the crystal structure, the molecules are linked into a ribbon-like structure along the a axis by O/C—H⋯O hydrogen bonds involving water molecules and C—H⋯π interactions involving the sulfonyl-bound phenyl ring. Adjacent ribbons are cross-linked via C—H⋯O hydrogen bonds involving a sulfonyl O atom and C—H⋯π interactions involving the pyridinone ring.