(±)-N-[4-Acetyl-5-methyl-5-(4-methyl­cyclo­hex-3-en­yl)-4,5-dihydro-1,3,4-thia­diazol-2-yl]acetamide

The new title thiadiazole compound, C14H21N3O2S, was semi-synthesized starting from 1-(4-methyl­cyclo­hex-3-en­yl)ethanone, a natural product isolated from Cedrus atlantica essential oil. The stereochemistry has been confirmed by single-crystal X-ray diffraction. The thia­diazo­line ring is roughly planar, although it may be regarded as having a half-chair conformation. The cyclo­hexenyl ring has a half-chair conformation. The most inter­esting feature is the formation of a pseudo-ring formed by four mol­ecules associated through N—H⋯O hydrogen bonds around a fourfold inversion axis, forming an R 4 4(28) motif

2-Acetyl-3,5,5,9-tetra­methyl-6,7,8,9-tetra­hydro-5H-benzocyclo­hepten-7-one

The title compound, C17H22O2, was semi-synthesized from a mixture of α-atlantone (Z) and α-atlantone (E), which were isolated from the essential oil of the Atlas cedar (cedrus atlantica). The mol­ecule consists of fused six- and seven-membered rings. The seven-membered ring is in a screw-boat conformation

N-[4-Acetyl-5-methyl-5-(2-p-tolyl­prop­yl)-4,5-dihydro-1,3,4-thia­diazol-2-yl]acetamide

The title heterocyclic compound, C17H23N3O2S, was synthesized from 4-(4-methyl­cyclo­hex-3-en­yl)pent-3-en-2-one, which was isolated from Cedrus atlantica essential oil. The thia­diazole ring adopts a flattened envelope conformation, with the flap sp 3-hybridized C atom lying 0.259 (1) Å out of the plane of the other four atoms. The screw-related mol­ecules are linked into chains along the b axis by inter­molecular N—H⋯O hydrogen bonds

N-[4-Acetyl-5-isobutyl-5-(2-p-tolyl­prop­yl)-4,5-dihydro-1,3,4-thia­diazol-2-yl]acetamide ethyl acetate hemisolvate

The racemic title compound, a new terpenoid, C20H29N3O2S·0.5C4H8O2, was synthesized from Cedrus Atlantica essential oil. The compound crystallizes with a disordered ethyl acetate solvent mol­ecule. The thia­diazole ring is almost planar, with a maximum deviation from the mean plane of 0.015 (2) Å for the C atom connected to the isobutyl group and has a puckering amplitude of 0.026 (2) Å. The dihedral angle between the benzene and thia­diazole rings is 18.32 (8)°. The crystal packing involves inter­molecular N—H⋯O hydrogen bonds

(4aS,10aS)-7-Hydr­oxy-8-isopropyl-1,1,4a-trimethyl-1,2,3,4,4a,9,10,10a-octa­hydro­phenanthrene: a new diterpenoid compound

The new title diterpenoid compound, C20H30O, is a natural product isolated from Tetra­clinis articulata wood via chloro­form extraction. The asymmetric unit contains four mol­ecules with the same S,S configuration, deduced from the chemical synthesis. Indeed, an overlay analysis, calculated using structure-matching software, shows that the four mol­ecules can be superimposed. The central ring has a half-chair conformation, whereas the saturated ring displays a chair conformation

7-Hy­droxy-8-isopropyl-1,1,4a-trimethyl-4a,9,10,10a-tetra­hydro-phenanthren-2(1H)-one

The title compound, C20H26O2, was isolated from a chloro­form extract of Tetra­clinis articulata wood. The mol­ecule contains three fused rings which exhibit different conformations. The non-aromatic oxo-substituted ring has a screw-boat conformation, while the central ring has a half-chair conformation. In the crystal, mol­ecules are linked to each other by inter­molecular O—H⋯O hydrogen bonds involving the carbonyl and hy­droxy groups

N-[4-Acetyl-5-(2-methylprop-1-enyl)-5-(2-p-tolyl­prop­yl)-4,5-dihydro-1,3,4-thia­diazol-2-yl]acetamide

The title heterocyclic compound, C20H27N3O2S, was synthesized from 2-(4-methyl­cyclo­hex-3-en­yl)-6-methyl­hepta-2,5-dien-4-one, which was isolated from the essential oil Cedrus atlantica. The thia­diazole ring is essentially planar [maximum deviation 0.006 (2) Å] and it forms a dihedral angle of 18.08 (9)° with the benzene ring. The dihedral angle between the thia­diazole ring and the acetamide plane is 7.62 (10)°. In the crystal, mol­ecules are linked into chains running along the c axis by inter­molecular N—H⋯O hydrogen bonds

4α,14α,Dimethyl-5α-cholest-8-en-3-one thiosemicarbazone

The compound 2 was prepared from equimolecular quantity of 1 (1g, 2.43 mmol), derivative triterpene resulting from Euphorbia officinarum1, and thiosemicarbazide2,3 dissolved in ethanol with several drops of conc. H2SO4.[...