In the title compound, C(16)H(26)NO(2) (+)·C(4)H(5)O(6) (-)·2H(2)O, a meptaz-inol derivative, three C atoms of the azepane ring are disordered over two positions, with site-occupancy factors of 0.80 and 0.20; the major disorder component adopts a twist-chair conformation, while the minor component has a chair conformation. The benzene ring is axially substituted on the heterocyclic ring, result...

In the crystal structure of the title compound, C(21)H(32)O(2), ring A is highly distorted, with a conformation inter-mediate between 10β-sofa and 1α,10β-half chair; rings B and C have slightly flattened chair conformations. Ring D assumes an unusual 13β-envelope conformation, probably induced by the acet-oxy substituent. Cohesion of the crystal structure is due only to weak van der Waals inter...

The title triterpene compound, C(23)H(32)O(4), isolated from Commiphora wightii features four trans-fused rings, among which the five-membered ring adopts an envelope conformation, the cyclo-hexene ring adopts a half-chair conformation and the two cyclo-hexane rings exist in chair conformations. The asymmetric unit contains two independent mol-ecules. Weak inter-molecular C-H⋯O hydrogen bonding...

In the title compound, C(26)H(30)N(2)O(4)S, the thio-morpholine ring adopts a chair conformation whereas the tetra-hydro-pyridine ring is in a half-chair conformation. The dihedral angle between the two phenyl rings is 33.3 (2)°. A strong intra-molecular O-H⋯O hydrogen bond generates an S(6) motif. In the crystal, mol-ecules are linked by inter-molecular C-H⋯O hydrogen bonds, generating a ribbo...

The new title diterpenoid compound, C(20)H(30)O, is a natural product isolated from Tetra-clinis articulata wood via chloro-form extraction. The asymmetric unit contains four mol-ecules with the same S,S configuration, deduced from the chemical synthesis. Indeed, an overlay analysis, calculated using structure-matching software, shows that the four mol-ecules can be superimposed. The central ri...

The title compound, C(41)H(70)O(12)·CH(4)O, was prepared by microbial transformation. Within the steroid skeleton of the mol-ecule, three six-membered rings exhibit a chair conformation, while the five -membered ring adopts an envelope conformation. The two pyranosyl rings also adopt chair conformations. The mol-ecules are held together by an extensive O-H⋯O hydrogen-bonding network.

In the title compound, C(23)H(34)O(4), the C/D and D/E rings are trans fused and the A/B ring possesses an anti fusion. The two cyclo-hexane rings adopt a chair conformation while the cyclo-hexene ring exhibits a half-chair conformation. The cyclo-pentane ring displays an envelope conformation with the C atom bearing the methyl group as the flap. In the crystal, the mol-ecules are linked by O-H...

In the title compound, C(30)H(52)O(5), the three six-membered rings are in chair conformations, the five-membered ring is in an envelope form and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and sofa. Intra-molecular O-H⋯O hydrogen bonds may influence the conformation of the mol-ecule. In the crystal, mol-ecules are linked by inter-molecular O-H⋯O hydrogen bond...

The title compound, C(24)H(37)BrO(3), is a tetra-cyclic diterpenoid with a beyerane skeleton, synthesized by esterification of isosteviol. It comprises a fused four-ring system A/B/C/D. Rings A and B have a chair conformation, whereas ring C is an unsymmetrical distorted chair; the remaining five-membered ring D adopts an envelope conformation. The stereochemistry of the A/B and B/C ring juncti...

In the racemic title compound, C(22)H(21)NO(3), the nitro-gen-containing ring of the pyran-oquinoline moiety adopts a slightly distorted half-chair conformation and the oxygen-containing ring adopts a slightly distorted chair conformation. The benzene rings make a dihedral angle of 84.97 (8)°. In the crystal, weak C-H⋯O inter-actions link the mol-ecules into chains extending along the a-axis di...