(6aS*,6bS*,11R*,11aR*)-6-(2-Furylmethyl)-5,12-dioxo-5,6,6a,6b,7,11,11a,12-octahydrofuro[3′,2′:5,6]isoindolo[2,1-a]quinazoline-11-carboxylic acid

Abstract

The title compound, C23H18N2O6, is the product of an intra­molecular thermal cyclo­addition within 1-malein-2-[(E)-2-(2-fur­yl)vin­yl]-4-oxo-3,4-dihydro­quinazoline. The mol­ecule comprises a previously unknown fused penta­cyclic system containing two five-membered rings (2-pyrrolidinone and furan) and three six-membered rings (benzene, 2,3-dihydro-4-pyrimidinone and dihydro­cyclo­hexa­ne). The central five-membered pyrrolidinone ring has the usual envelope conformation. The six-membered dihydro­pyrimidinone and dihydro­cyclo­hexane rings adopt a half-boat and a half-chair conformation, respectively. The dihedral angle between the planes of the terminal benzene and furan rings is 45.99 (7)°. In the crystal, O—H⋯O hydrogen bonds link the mol­ecules into centrosymmetric dimers. Weak C—H⋯O hydrogen bonds consolidate further the crystal packing, which exhibits π–π inter­actions, with a short distance of 3.556 (3) Å between the centroids of benzene rings of neighbouring mol­ecules.

Crystal structure of (±)-(3aR,5R,8bR)-5-hydroperoxy-2-phenyl-6-tosyl-4,5,6,8b-tetrahydropyrrolo[3,4-e]indole-1,3(2H,3aH)-dione

“…Of 13 total entries, none was found containing sulfur atoms. Ten exhibit intermolecular hydrogen bonding, but only two of them are tandem-bonded dimers [pyrimidinone carbonyl to carboxylic acid (Obushak et al, 2011); succinimide dimerization between N-H and a carbonyl oxygen (Beccali et al, 1996)]. None of these structures resembles that of compound (I).…”

(4R*,4aR*,7aS*)-5-Oxo-6-phenyl-4a,5,6,7,7a,8-hexahydro-4H-furo[2,3-f]isoindole-4-carboxylic acid

“…For heterolignan derivatives, see: Ramos et al (1999); Leteurtre et al (1992) and for their pharmaceutical properties, see: Iwasaki et al (1996); Ducharme et al (1994). For a related structure, see: Obushak et al (2011). For puckering parameters, see: Cremer & Pople (1975).…”