The title compound, C27H47NO, is a steroid derivative composed of a saturated carbon fused-ring framework with an alkyl side chain. Ring bond lengths have normal values with an average of 1.533 (2) Å, while the cholestane side chain shows an average bond length of 1.533 (2) Å. The three cyclohexane rings adopt chair conformations or close to chair conformations while the cyclopentane ring is twisted. The cholesterol side-chain is fully extended with a gauche–trans conformation of the terminal methyl groups. There are eight chiral centres in the molecule; the absolute configuration of these sites was determined from the structure presented. There are two molecules in the asymmetric unit; in one, the alkyl chain is disordered over two sets of sites [occupancy ratios of 0.50:0.50 and 0.67:0.33].
The title compound, C27H45Cl, is a second monoclinic polymorph which crystallizes in the space group P21 with four crystallographically independent molecules in the asymmetric unit. The structure was previously reported [Bernal et al. (1940 ▶). Philos. Trans. R. Soc. London Ser. B, 239, 135–182; Vani & Vijayan (1979 ▶). Mol. Cryst. Liq. Cryst.
51, 253–264], also in the space group P21, but with two unique molecules in the asymmetric unit. As in the previously reported structures, rings A and C in the molecule adopt chair conformations with half-chair conformations for rings B and D. The ring junctions B–C and C–D are trans, whereas the junction A–B is quasi-trans. In the crystal structure, molecules are arranged in a head-to-tail fashion along a and are stacked along the b axis.
The title steroid, C23H35ClO4, is a pregnane derivative prepared by ring opening of the corresponding 5α,6α-epoxy steroid with BiCl3. There are two symmetry-independent molecules in the asymmetric unit that show no significant differences concerning bond lengths and angles. The conformation of the six-membered rings in both molecules is close to a chair form, while the five-membered ring adopts an envelope conformation. All rings in both molecules are trans-fused. The molecules are held together by an extensive O—H⋯O hydrogen-bonding network.
In the title compound, C25H25ClO2, the C ring adopts a chair conformation, while the B ring approximates a half-chair conformation. The five-membered ring D has a twist conformation on the C—C bond fused with the C ring. Aromatic rings A and E are not coplanar, as evidenced by the dihedral angle of 7.51 (1)°. In the crystal, O—H⋯O hydrogen bonds form a double chain along the ab plane interconnected by C—H⋯O interactions.
In the title compound, C31H29ClN2O2S, the pyrrolidine ring adopts an envelope conformation with the methine C atom adjacent to the NH group as the flap atom. The tetrahydropyridine ring has a half-chair conformation. The two rings are trans-fused. The chlorobenzene ring and the adjacent phenyl ring form a dihedral angle of 77.9 (1)°. The benzyl phenyl and the tosyl phenyl rings are oriented at a dihedral angle of 88.0 (1)°. In the crystal, molecules are linked into chains along the a axis by N—H⋯Cl and C—H⋯Cl hydrogen bonds and the adjacent chains are cross-linked via C—H⋯π interactions.
In the title compound C27H19ClO6, the coumarin ring system is not exactly planar, with a dihedral angle of 4.12 (7)° between its benzene and lactone rings. The cis-fused pyran rings adopt half-chair conformations. The carbomethoxy and chlorophenyl groups are in a trans configuration. The crystal packing is stabilized by intermolecular C—H⋯O interactions, which produce a centrosymmetric R
2(14) dimer and two centrosymmetric R
2(18) dimers connecting the molecules in a two-dimensional fashion.
In the title compound, C13H11ClO2, the dihedral angle between the mean planes of the 2-chlorophenyl and phenol rings is 87.4 (9)°. The methyl hydroxy group lies nearly perpendicular to the plane of its attached benzene ring [O—C—C—C torsion angle = 84.3 (3)°]. The two hydroxy groups lie on the same side of the molecule and are in a slightly twisted gauche conformation [O—C—C—O torsion angle = 77.1 (8)°] to each other. In the crystal, O—H⋯O hydrogen bonds between nearby methylhydroxy groups form dimers in alternating pairs aligned diagonally along the b axis. A view along the c axis reveals a hexameric aggregate mediated by a ring of six O—H⋯O hydrogen bonds generating an R
6(12) motif loop.
In the title molecule, C11H11ClO3, the fused pyran ring adopts a half-chair conformation. In the crystal, intermolecular O—H⋯O hydrogen bonds link molecules into chains along . These chains are interconnected by weak intermolecular C—H⋯O contacts which generate R
2(8) ring motifs, forming sheets parallel to (001). Tetragonal symmetry generates an equivalent motif along b. Furthermore, the sheets are linked along the c axis by offset π–π stacking interactions involving the benzene rings of adjacent molecules [with centroid–centroid distances of 3.839 (2) Å], together with an additional weak C—H⋯O hydrogen bond, resulting in an overall three-dimensional network.
The asymmetric unit of the title compound, C27H45ClO, consists of two crystallographically independent molecules. In both molecules, the three cyclohexane rings in the steroid fused-ring systems adopt chair conformations, while the cyclopentane ring adopts a half-chair conformation in one molecule and an envelope conformation in the other. In the crystal, the molecules are linked into a two-dimensional network by weak C—H⋯O hydrogen bonds. The crystal studied is a nonmerohedral twin with a refined ratio of twin components of 0.264 (3):0.736 (3).
The title compound, C32H49ClO4, was obtained along with nitrile and lactam products in the POCl3-catalysed Beckmann rearrangement from 3β-acetoxy-12-hydroxyiminoolean-28-olic acid methyl ester. The mechanism of the transformation leading to the title compound remains unclear and requires further investigation. Rings A, B and E are in chair conformations, ring C has a twisted-boat conformation, ring D a conformation halfway between boat and twisted-boat and rings D and E are cis-fused. In the crystal, molecules are connected by weak intermolecular C—H⋯O hydrogen bonds into layers extending parallel to the bc plane.
In the asymmetric unit of the title compound, C38H56O3, there are two symmetry-independent molecules that differ in the rotation angle along the C—O bond between the 3-(4-ethoxyphenyl)prop-2-enoate and cholest-5-en-3β-yl groups by 169.3 (3)°. In both molecules, steroid ring B adopts a half-chair conformation, rings A and C adopt a chair conformation and ring D exists in an envelope form. The two symmetry-independent molecules pack in the crystal into separate layers parallel to (-102) with their long axis parallel to the  direction. Short intermolecular C—H⋯O and C—H⋯π contacts are observed.
In the title compound, C19H19ClO4, the central fused ring and the attached cyclohexene ring adopt envelope conformations, while the cyclohexane ring adopts a chair conformation. The crystal packing is stabilized by O—H⋯O hydrogen bonds, which link the molecules into a chain along the b axis. Weak C—H⋯O bonds also occur.
The title compound, C31H48O7, a polyoxygenated steroid, was obtained by chemical oxidation of 7-dehydrocholesteryl acetate. The molecular geometry features trans A/B and C/D junctions at the steroid core with the acetyl groups in the equatorial position and a fully extended conformation for the alkyl side chain. A chair conformation is observed for rings A and C while ring B adopts a half-chair conformation. The five-membered ring D has an envelope conformation, with the C atom bearing the methyl group at the flap. The terminal isopropyl group and one acetyl group are disordered over two sets of sites with 0.774 (8):0.226 (8) and 0.843 (7):0.157 (7) ratios, respectively. An intramolecular S(6) O—H⋯O hydrogen-bonding motif involving a hydroxy donor and acceptor is observed. In the crystal, chains of molecules running along the b axis are formed via O—H⋯O hydrogen bonds between hydroxy donors and carbonyl acceptors of the ordered acetyl group, giving rise to a C(14) motif. The chains are wrapped around the 21 screw axes.
In the title compound, C37H32Cl2N2O2, the pyridinone ring adopts a twisted half-chair conformation. The fused pyrrolidine and piperidine rings of the octahydroindolizine unit exhibit envelope (with the C atom bound to the C atom bearing the chlorobenzene ring being the flap atom) and chair conformations, respectively. The dihedral angle between the chlorobenzene rings is 84.03 (1)°. In the crystal, C—H⋯π interactions lead to supramolecular chains along  that assemble in the ac plane. Connections along the b axis are of the type Cl⋯Cl [3.4065 (8) Å].
The asymmetric unit of the title compound, C30H48ClN3O, contains two molecules, A and B. In both molecules, the three cyclohexane rings in the steroid fused ring systems adopt chair conformations, while the cyclopentane rings adopt envelope and twist conformations in molecules A and B, respectively. In molecule B, the cyano group is disordered over two orientations with refined site-occupancies of 0.593 (8) and 0.407 (8). An intramolecular C—H⋯N interaction forms an S(10) ring in both molecules. In the crystal, molecules are linked by N—H⋯O, C—H⋯O and C—H⋯N interactions, resulting is chains propagating along the a-axis direction.
The title compound, C24H34O5, a fungal-transformed metabolite of the injectable contraceptive medroxyprogesterone acetate, consists of four fused rings (A, B, C and D; steroid labelling). Ring A exists in a half-chair conformation while trans-fused rings B and C adopt chair conformations. The five-membered ring D adopts an envelope conformation with the C atom bound to the methyl group at the flap. In the crystal, adjacent molecules are linked by O—H⋯O and C—H⋯O hydrogen bonds, forming infinite chains along the a axis.
In the title compound, C19H16BrClO4, both the fused xanthene rings and one of the cyclohexane rings adopt envelope conformations, while the other cyclohexane ring is in a chair conformation. In the crystal, molecules are linked by C—H⋯O hydrogen bonds, forming infinite chains running along [10-1] incorporating R
2(16) ring motifs. In addition, C—H⋯π interactions and weak π–π stacking interactions [centroid–centroid distance = 3.768 (3) Å] help to consolidate the packing.
In the title molecule, C13H21ClO2, there is an intramolecular C—H⋯Cl hydrogen bond. The conformation about the C=C bond is E and the six-membered ring has a chair conformation. In the crystal, molecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers, which are consolidated by C—H⋯O hydrogen bonds. The dimers are linked via C—H.·O hydrogen bonds, forming chains along .
The title compound, C37H31ClN4O4, crystallizes with two molecules (A and B) in the asymmetric unit. The pyrrole rings in both molecules are connected via cis fusion, whereas one ring has a twisted conformation and the other assumes a half-chair conformation. In the crystal, the A molecules form inversion dimers via a pair of C—H⋯Cl interactions, while the B molecules form chains propagating in , via C—H⋯O interactions. In the crystal, there are also a number of C—H⋯π interactions present.
The title compound, C21H29ClO3 [systematic name (8R,9S,10R,13S,14S,17S)-4-chloro-3-oxoandrost-4-en-17β-yl acetate], is a 4-chloro derivative of testosterone, used as an anabolic androgenic agent or applied topically in ophthalmological and dermatological treatments. The absolute configurations at positions 8, 9, 10, 13, 14 and 17 were established by refinement of the Flack parameter as R, S, R, S, S, and S, respectively. Rings B and C of the steroid ring system adopt chair conformations, ring A has a half-chair conformation, while ring D is in a C13 envelope conformation. Ring B and C, and C and D are trans fused. In the crystal, molecules are linked by a weak C—H⋯O interaction.
The title compound, C25H33ClN2O5, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylene-3,14-dioxatricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from fused five- and ten-membered rings with two additional epoxy ring systems and a chlorophenylpiperazine group as a substituent. The ten-membered ring adopts an approximate chair–chair conformation, while the piperazine ring displays a chair conformation and the five-membered ring shows an envelope conformation with the C atom closest to the hydroxy group forming the flap. The molecular conformation is stabilized by an intramolecular O—H⋯N hydrogen bond between the hydroxy group and a piperazine N atom. The crystal structure is stabilized by weak C—H⋯O interactions.
In the title compound, C16H18ClN3O, the cyclohexane ring adopts a distorted chair conformation. In the crystal, pairs of molecules are linked by N—H⋯O hydrogen bonds into inversion dimers, forming R
2(10) ring motifs. These dimers are connected through C—H⋯N hydrogen bonds into chains along the a axis, forming layers parallel to (101).
In the title compound, C14H16ClNO2, the cyclohexyl ring has a chair conformation. The dihedral angle between the benzene ring and the mean plane of the four planar C atoms of the cyclohexyl ring is 45.2 (3)°. The two carbonyl groups are trans to one another, with an O=C—C=O torsion angle of −137.1 (3)°. In the crystal, molecules are linked by N—H⋯O hydrogen bonds forming chains propagating along . A region of disordered electron density, situated near the unit-cell corners, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155]. It gave a solvent-accessible void of ca 400 Å3 for only 21 electrons. It is probably due to traces of the solvent of crystallization and was not taken into account during structure refinement.
In the title compound, C26H25Cl2NO2, the piperidine ring adopts a chair conformation with a cis configuration of the carbonyl and hydroxy substituents. The dihedral angle between the aromatic rings of the chlorobenzene groups is 24.3 (2)°. The phenyl ring forms dihedral angles of 59.4 (3) and 44.1 (3)° with the benzene rings. In the crystal, molecules are linked by intermolecular O—H⋯N and C—H⋯O hydrogen bonds and C—H⋯π interactions into layers parallel to the bc plane.
The title compound, C21H24N2O2, is a phenyl hydrazine derivative of the well known anthelminthic agent α-santonin, which is composed of three fused rings (benzodieneone, cyclohexane and γ-lactone). The cyclohexadienone ring adopts a boat conformation, the cyclohexane ring is in a chair conformation and the trans-fused γ-lactone ring adopts a C-envelope conformation. In the crystal, molecules are linked by N—H⋯O and C—H⋯O hydrogen bonds, forming chains along the a axis.