8,13,26-Trioxa-23-thia-21-aza­penta­cyclo­[18.6.0.0^2,7.0^14,19.0^21,25]hexa­cosa-2(7),3,5,14,16,18-hexa­ene

In the title compound, C₂₁H₂₃NO₃S, both the thia­zole and oxazolidine rings adopt twist conformations. The mean plane of the thia­zole ring makes a dihedral angle of 61.02 (7)° with the oxazolidine ring mean plane, and dihedral angles of 22.72 (6) and 75.07 (6)° with the benzene rings. The benzene rings are almost perpendicular to one another, making a dihedral angle of 89.14 (6)°. There are bifurcated intra­molecular C—H...O hydrogen bonds in the mol­ecular structure. In the crystal, mol­ecules are linked via C—H...π inter­actions, forming chains propagating along [100].

8,11,24-Trioxa-21-thia-19-aza­penta­cyclo­[16.6.0.0^2,7.0^12,17.0^19,23]tetra­cosa-2(7),3,5,12,14,16-hexa­ene

In the title compound, C₁₉H₁₉NO₃S, the thia­zole and oxazolidine rings each adopt an envelope conformation, with the S and O atoms as the respective flap atoms. The thia­zole and oxazolidine rings (all atoms) make a dihedral angle of 66.39 (11)° while the phenyl rings subtend a dihedral angle of 22.71 (10)°.

6a-Nitro-6-phenyl-6,6a,6b,7,8,9,10,12a-octa­hydro­spiro­[chromeno[3,4-a]indol­izine-12,3′-indolin]-2′-one

In the title compound, C₂₈H₂₅N₃O₄, the central pyrrolidine ring adopts adopts an envelope conformation with the N atom as the flap and the piperidine ring adopts a chair conformation. The pendant pyrrolidine ring is almost planar (r.m.s. deviation = 0.008 Å). An intra­molecular C—H...O inter­action closes an S(6) ring. In the crystal, inversion dimers linked by pairs of N—H...O hydrogen bonds generate R₂²(8) loops.