Moha Berraho

(1S,3R,8R,9R,10S)-2,2-Dibromo-3,7,7,10-tetra­methyl-9β,10β-ep­oxy-3,7,7,10-tetra­methyl­tricyclo­[6.4.0.01,3]dodeca­ne

The title compound, C16H24Br2O, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (Cedrus atlantica). The molecule contains fused six- and seven-membered rings, each linked to a three-membered ring. The six-membered ring has a half-chair conformation, while the seven-membered ring displays a chair conformation. The dihedral angle between the mean planes through the six- and seven-membered rings is 39.55 (12)°. The two three-membered rings, linked to the six- and seven-membered rings, are nearly perpendicular to the six-membered ring, making dihedral angles of 78.6 (2) and 80.5 (2)°, respectively. The absolute structure was established unambiguously from anomalous dispersion effects. In the crystal, each molecule is linked to its symmetry-equivalent partner by C—H⋯O hydrogen bonds, forming zigzag chains parallel to [100].

(1S,3R,8R,9S,11R)-2,2,10,10-Tetra­chloro-3,7,7,11-tetra­methyl­tetra­cyclo­[6.5.0.01,3.09,11]trideca­ne

The title compound, C17H26Cl2, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The asymmetric unit contains two independent molecules with similar conformations. Each molecule is built up from fused six- and seven-membered rings and two three-membered rings from the reaction of β-himachalene with dichlorocarbene. In both molecules, the six-membered ring has a half-chair conformation, whereas the seven-membered ring displays a boat conformation. The absolute configuration was established from anomalous dispersion effects.

Crystal structure of 1-isopropyl-4,7-dimethyl-3-nitro­naphthalene

The title compound, C15H17NO2, was synthesized from a mixture of α-himachalene (2-methylene-6,6,9-trimethylbicyclo[5.4.01,7]undec-8-ene) and β-himachalene (2,6,6,9-tetramethylbicyclo[5.4.01,7]undeca-1,8-diene), which were isolated from an oil of the Atlas cedar (Cedrus Atlantica). The naphthalene ring system makes dihedral angles of 68.6 (2) and 44.3 (2)°, respectively, with its attached isopropyl C/C/C plane and the nitro group. In the crystal, molecules held together by a C—H⋯O interaction, forming a chain along [-101].

(1S,3R,8R,9S,11R)-2,2,10,10-Tetrachloro-3,7,7,11-tetramethyltetracyclo[6.5.0.01,3.09,11]tridecane

The title compound, C17H24Cl4, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The molecule is built up from fused six- and seven-membered rings and two three-membered rings from the reaction of β-himachalene with dichlorocarbene. The six-membered ring shows a chair conformation, whereas the seven-membered ring displays a boat conformation.

9β-Hy­droxy-1β,10α-ep­oxy­parthenolide

The title compound, C15H20O5 (systematic name: 5-hydroxy-1a,4a-dimethyl-7-methyleneperhydrodioxireno[5,6:9,10]cyclodeca[1,2-b]furan-8-one), was obtained by the reaction of 3-chloroperbenzoic acid with 9β-hydroxyparthenolide. The five-membered ring adopts a twist conformation, whereas the ten-membered ring displays an approximate chair–chair conformation. In the crystal structure, molecules are linked into chains propagating along the b axis by intermolecular O—H⋯O hydrogen bonds.

1-[(1S,6R,7S,9R)-8,8-Di­bromo-5,5,9-tri­methyl­tri­cyclo­[4.4.0.17,9]decan-1-yl]ethanone

The title compound, C16H24Br2O, was synthesized by three steps from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from essential oil of the Atlas cedar cedrus atlantica. The asymmetric unit contains two independent molecules with almost identical conformations. Each molecule is built up from two fused six-membered rings, one having a chair conformation and the other a boat conformation, and an additional three-membered ring arising from the reaction of himachalene with dibromocarbene. In the crystal, there are no significant intermolecular interactions present. The absolute structure of the title compound was confirmed by resonance scattering.

(1S,3R,8S,9R,10S)-2,2-Dichloro-3,7,7,10-tetra­methyl-9,10-ep­oxy­tricyclo­[6.4.0.01,3]dodeca­ne

The title compound, C16H24Cl2O, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (cedrus atlantica). The molecule forms an extended sheet of two fused rings which exhibit different conformations. The six-membered ring has a half-chair conformation, while the seven-membered ring displays a chair conformation; the dihedral angle between the two rings is 38.2 (1)°.

(1R,4R,6S,7R)-5,5-Di­bromo-1,4,8,8-tetra­methyl­tri­cyclo­[5.4.1.04,6]dodecan-12-one

The title compound, C16H24Br2O, was synthesized from the reaction of β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from Atlas cedar (Cedrus atlantica). The asymmetric unit contains two independent molecules with similar conformations. Each molecule is built up from two fused seven-membered rings and an additional three-membered ring. In both molecules, one of the seven-membered rings has a chair conformation, whereas the other displays a screw-boat conformation.

2,2-Dichloro-3,7,7,11-tetra­methyl-10-aza­tetra­cyclo­[6.5.0.01,3.09,11]trideca­ne

The title compound, C16H25Cl2N, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The molecule is built up from fused six- and seven-membered rings linked to two three-membered rings. The six-membered ring shows a half-chair conformation, whereas the seven-membered ring displays a boat conformation. The dihedral angle between the mean planes through the six- and seven-membered rings is 59.8 (2)°. The two three-membered rings lie to one side and each is nearly perpendicular to the six-membered ring, forming dihedral angles of 83.2 (2) and 86.0 (2)°. The absolute structure was established unambiguously from anomalous dispersion effects. No specific intermolecular interactions are noted in the crystal structure.

(1S,3R,8R)-2,2-Dibromo-3,7,7,10-tetra­methyl­tricyclo­[6.4.0.01,3]dodec-9-ene

The title compound, C16H24Br2, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The molecule is built up from two fused six- and seven-membered rings and an additional three-membered ring from the reaction of β-himachalene with dibromocarbene. The six-membered ring shows a screw-boat conformation, whereas the seven-membered ring displays a boat conformation; the dihedral angle between the mean planes through the rings is 57.9 (4)°. The absolute structure was established unambiguously from anomalous dispersion effects.