Highly regio- and diastereo-selective synthesis of novel tri- and tetra-cyclic perhydroquinoline architectures via an intramolecular [3 + 2] cycloaddition reaction.

A facile and efficient synthetic protocol was established for the construction of novel tri- and tetra-cyclic pyrrolo/pyrrolizinoquinoline architectures via the in situ formation of azomethine ylide followed by an intramolecular [3 + 2] cycloaddition reaction strategy. This protocol leads to the creation of two/three new rings and three/four contiguous stereocentres, in which one of them is a tetra-substituted carbon center, in a highly diastereoselective fashion with excellent yields.

Crystal structure of methyl 6-meth-oxy-11-(4-meth-oxy-phen-yl)-16-methyl-14-phenyl-8,12-dioxa-14,15-di-aza-tetra-cyclo-[8.7.0.0(2,7).0(13,17)]hepta-deca-2(7),3,5,13(17),15-penta-ene-10-carboxyl-ate.

In the title compound, C30H28N2O6, the pyran ring adopts a slightly distorted half-chair conformation and the pyrone ring adopts an envelope conformation, with the C atom bearing the carboxyl-ate group as the flap. The pyrazole ring [maximum deviation = 0.002 (2) Å] forms a dihedral angle of 13.2 (1)° with the attached benzene ring. The near-planar atoms of the pyran ring and the pyrazole ring are close to coplanar, the dihedral angles between their mean planes being 6.4 (1)°. The dihedral angle between the pyrone ring and the benzene ring of the chromene unit is 10.7 (1)°. The mol-ecular conformation is stabilized by an intra-molecular C-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, C-H⋯O inter-actions generate supra-molecular chains propagating in [100] and these are connected into double layers that stack along the c-axis direction by weak π-π inter-actions between pyrazole rings [centroid-centroid distance = 3.801 (1) Å].

Crystal structure of (Z)-3-(4-meth-oxy-benzyl-idene)-2,3-di-hydro-benzo[b][1,4]thia-zepin-4(5H)-one.

In the title compound, C17H15NO2S, the two C atoms linking the S and carbonyl C atoms of the seven-membered thia-zepine ring are disordered over two sites, with occupancies of 0.511 (4) and 0.489 (4); both disorder components adopt distorted twist-boat conformations. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds link inverted-related mol-ecules into dimers, incorporating R 1 (2)(6) and R 2 (2)(8) ring motifs; the acceptor carbonyl O atom is bifurcated. These dimers are further linked by C-H⋯O hydrogen bonds, forming supra-molecular tapes running along the a axis.