Synthesis,Characterization and Crystal Structure of (<Emphasis Type="Italic">S</Emphasis>)-2-(2-Hydroxynaphthalen-6-yl)-<Emphasis Type="Italic">N</Emphasis>-((pyridin-4-yl)methyl) Propanamide

Abstract  

The synthesis, characterization and crystal structure of the title compound, (S)-2-(2-hydroxynaphthalen-6-yl)-N-((pyridin-4-yl)methyl) propanamide, is described. The salt is enantiomerically pure and crystallize in the orthorhombic P2₁2₁2₁ chiral space group with a = 7.9174(13) ?, b = 11.1583(18) ?, c = 11.2600(18) ?. Each molecule is linked to four neighboring molecules through the O–H···O and N–H···N hydrogen bonds into a supramolecular helical chain. The O–H···O and N–H···N hydrogen bonds lead to 24-membered open rings. Chains are further connected into layers via extensive interchain H···O and H···C short contacts.     

Experimental and Semi-Empirical and DFT Calculational Studies on (<Emphasis Type="Italic">E</Emphasis>)-2-[(2,4-Dichlorophenylimino) methyl]-<Emphasis Type="Italic">p</Emphasis>-cresol

Abstract  

The molecular and crystal structure of the title compound, C₁₄H₁₁Cl₂NO, has been determined by X-ray single crystal diffraction technique. The compound crystallizes in the orthorhombic, space group Pbca with unit cell dimensions a = 7.5537(10) ?, b = 11.5518(13) ?, c = 29.760(4) ?, M _r  = 280.14, V = 2596.8(6) ?³, Z = 8, R ₁ = 0.065 and wR ₂ = 0.191. The title compound exists in the enol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond. The dihedral angle between the two benzene rings is 37.66(15)°. The asymmetric unit in the crystal structure contains only one neutral molecule. Calculational studies were performed by using AM1, PM3, PM6 semi-empirical and DFT methods. Geometry optimizations of compound have been carried out by using three semi-empirical methods and DFT method and bond lengths, bond and torsion angles of title compound have been determined. Dipole moments (Debye) and the energy parameters of compound (kcal/mol) were calculated by using above mentioned calculation methods. Atomic charge distribution has been obtained from AM1, PM3, PM6 and DFT. In order to determine conformational flexibility on the molecule, molecular energy profile of the title compound was obtained with respect to the selected torsion angle T(N1–C7–C1–C2), which is varied from −180° to +180° in every 10 via PM3 semi-empirical method.     

Crystal Structure of 2-<Emphasis Type="Italic">Exo</Emphasis>-Phenyl-2,3,4,5-Tetrahydro-1,4-Epoxinafto[1,2-b]azepine

Abstract  

The title compound, C₂₀H₁₇NO, crystallizes in the orthorhombic P2₁2₁2₁ space group with unit cell parameters a = 7.6903(7) ?, b = 18.979(2) ?, c = 19.753(2) ?, with two crystallographically independent molecules in the asymmetric unit, which differ from one another in the slight rotation of the phenyl ring; this allows the formation of three internal hydrogen bonds, two of the type C–H···N and one of the type C–H···O, in one of the molecules, in contrast with only two of the type C–H···N in the other. The compound is rich in aromatic π rings and therefore the crystal packing is entirely dominated by cohesive weak C–H···π interactions among neighboring molecules producing an efficient packing with 71.2% of occupied space.     

Structure and Antibacterial Activity of 3-(3,4-Dimethoxyphenyl)furan-2(5<Emphasis Type="Italic">H</Emphasis>)-ones

Abstract  

Crystalline hydrate of the title compound (5), C₁₉H₂₆N₂O₅·2(H₂O), was structurally characterized by single crystal X-ray diffraction. It crystallizes in monoclinic system space group P 21/c with a = 7.3987(7) ?, b = 17.8691(16) ?, c = 17.0022(13) ?, β = 112.944(3)°, V = 2070.0(3) ?³, Z = 4, R ₁ = 0.0592, wR ₂ = 0.1016, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with 3,4-dimethoxybenzene ring, making a dihedral angle of 0.860(69)°. Two kinds of centrosymmetric tetramers characterized by graph-set motifs of R ₇⁸(36) and R ₄⁶(32) are formed through O–H···O, O–H···N and C–H···O hydrogen bonding interactions, which generate a sheet of edge-fused rings parallel to the (011) plane. These sheets are further linked into a three dimensional network by C–H···π interactions. Nine 3-(3,4-dimethoxyphenyl)furan-2(5H)-ones were synthesized and fully characterized by elemental analysis, MS and ¹H NMR. All of them were evaluated for antimicrobial activities against three Gram-positive organisms and a Gram-negative organism, and compound 5 was the most active against Staphylococcus aureus ATCC 25923.     

Structure of a New Bioactive Agent Containing Combined Antibacterial and Antifungal Pharmacophore Sites: 4-{[(<Emphasis Type="Italic">E</Emphasis>)-(5-Bromo-2-hydroxyphenyl)methylidene]amino}-<Emphasis Type="Italic">N</Emphasis>-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide

Abstract  

The title compound (3), C₁₇H₁₄BrN₃O₄S, is a Schiff base compound of 5-bromosalicylaldehyde (1) and sulfamethoxazole (2). The structure of (3) was determined by spectral (IR, ¹H and ¹³C NMR), elemental analyses and X-ray diffraction data. Compound (3) crystallizes in the monoclinic space group C2/c, with a = 31.936(3), b = 6.2571(5), c = 16.903(1) ?, β = 94.867(8), V = 3365.5(5) ?³, Z = 8. In the molecule of compound (3), the molecule is bent at the S atom with a C–SO₂–NH–C torsion angle of −86.3(3)°. Pairs of molecules, related by inversion centres, form intermolecular N–H···N hydrogen bonds to produce a dimer. An intramolecular phenolic O–H···N hydrogen bond is also formed. Intermolecular hydrogen bonding and π–π stacking hold the molecules together. The average distance between stacked benzene ring planes is 3.625(2) ?.     

Structures of Two (<Emphasis Type="Italic">E</Emphasis>)-3-Substituted Cinnamoylbenzotriazole 1-Oxides

Abstract  

The molecule of (E)-3-(3-MeOC₆H₄CH=CHCO)-benzotriazole 1-oxide, 2, has a very near planar structure, while the 2-nitrophenyl ring is rotated out of the plane of the remaining atoms in (E)-3-(2-O₂NC₆H₄CH=CHCO)-benzotriazole 1-oxide, 1. The nitrogen oxide bond lengths in 1 and 2 are 1.258 (6) and 1.2683 (15) ?, respectively, and are in the region found for related compounds. There are no strong intermolecular hydrogen-bonds in either compound, instead there are weak C–H···O intermolecular hydrogen-bonds and π···π stacking interactions in 1, and C–H···O, C–H···π, and π···π stacking interactions in 2. Different three-dimensional arrays are generated in each case. Compound 1 crystallises in the orthorhombic space group Pna2₁, with a = 25.061 (2) ?, b = 3.6997 (2) ?, c = 14.2623 (12) ? and Z = 4. Compound 2 crystallises in the triclinic space group P-1, with a = 5.7297 (3) ?, b = 10.8440 (6) ?, c = 11.4965 (6) ?, α = 89.689 (3)°, β = 76.019 (3)°, γ = 75.047 (3)°, Z = 2.     

Desynchronization of Pedal Motion: Crystallographic and Theoretical Study of (<Emphasis Type="Italic">E</Emphasis>)-4-[(4-ethylphenyl)diazenyl]-2-methylphenol

Abstract  The single crystal X-ray diffraction analysis of the title compound, C₁₅H₁₆N₂O, reveals that its molecules exhibit whole-molecule disorder at both crystal lattice sites due to pedal motion in solid state. The compound crystallizes in the monoclinic space group P 2₁/c with a = 20.5504(14) ?, b = 10.8887(5) ?, c = 12.0191(8) ? and β = 96.927(5)°. While major pedal conformers of the compound in solid state are stabilized by intermolecular O–H···N type hydrogen bonds leading to the formation of C(7) chains at Site 1 and C(8) chains at Site 2 along [0 1 0] axis, C–H···π type intermolecular interactions between major and minor conformers also serve to stabilize minor pedal conformers. An interesting feature about the crystal structure is that pedal conformers at Site 1 have two different occupancy factors arising from desynchronization of pedal motion along [2 1 0] direction in crystal phase. Quantum chemical calculations at the B3LYP/6-31++G** level suggest that the desynchronization of pedal motions make more unstable pedal conformers at Site 1 than those at Site 2. Index Abstract  Molecular and crystal structure of (E)-4-[(4-ethylphenyl)diazenyl]-2-methylphenol, C₁₆H₁₈N₂O, indicate desynchronization of pedal motion and the quantum chemical calculations at level of B3LYP/6-31++G** suggest that desynchronization of pedal motions make more unstable pedal conformers.      

Crystallographic and Conformational Analysis of [(<Emphasis Type="Italic">E</Emphasis>)-2-[(3-Chlorophenylimino)methy])-4-methoxyphenol]

Abstract  The crystal structure of C₁₄H₁₂ClNO₂ was determined by X-ray analysis. It crystallizes in the triclinic space group Pc with a = 12.5346(10) ?, b = 4.5101(3) ?, c = 12.0534(11) ?, α = 90.00o, β = 113.669(6)o, γ = 90.00o, Z = 2, Dx = 1.393 mg/m³, μ (MoK_α) = 0.298 mm⁻¹. The title compound is photochromic and molecule is non-planar. It adopts a phenol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond and a strong intermolecular C–H···O hydrogen bond. Minimum energy conformations AM1 were calculated as a function of the three torsion angles θ1(C10–C9–N1–C8), θ2(C9–N1–C8–C1) and θ3(N1–C8–C1–C6), varied every 10°. As in the X-ray experiment results, molecule has an angle that makes it non-planar between two aromatic rings in AM1 optimized geometry. Graphical Abstract  Molecular and crystal structure of [(E)-2-[(3-chlorophenylimino)methy])-4-methoxyphenol], C₁₄H₁₂ClNO₂, have been determined by single crystal X-ray diffraction study, and conformational analysis of the title molecule with respect to the selected torsion angle has been achieved by AM1 semi-empirical calculations.      

Synthesis and Crystal Structure of a New Schiff Base 4-[(2-hydroxy-benzylidene)-amino]-<Emphasis Type="Italic">N</Emphasis>-(5-methyl-isoxazol-3-yl)-benzenesulfonamide

Abstract  The structure of the title compound (C₁₇H₁₅N₃O₄S)₂ the schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was elucidated by H¹, C¹³ NMR, UV–VIS and IR spectroscopic techniques. The X-ray structure was determined in order to establish the conformation of the molecule. The compound crystallizes in the triclinic space group P-1, with a = 11.419(1), b = 11.426(0), c = 13.316(1) ?, α = 71.94(2), β = 89.79(1), γ = 89.14(2)° and Z = 4. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving the hydroxy O atom and azomethine N atom. The component species further interact via N–H···N and C–H···O hydrogen bonds and π–π stacking interactions. Index Abstract  The title compound (C₁₇H₁₅N₃O₄S)₂, Schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was synthesized by the condensation of 4-amino-N-(5-methyl-3-isoxazolyl) benzene sulfonamide (SMZ) and 2-hydroxy benzaldehyde (SA). Its structure was confirmed by single crystal X-ray diffraction analysis. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Synthesis,Crystal Structure and Spectroscopic Characterization of {6-[2-(2-chlorophenyl)-1,3-thiazol-4-yl]-2-oxo-1,3-benzothiazol-3(2<Emphasis Type="Italic">H</Emphasis>)-yl}acetic acid

Abstract  

The title compound {6-[2-(2-chlorophenyl)-1,3-thiazol-4-yl]-2-oxo-1,3-benzothiazol-3(2H)-yl}acetic acid was prepared and characterized by elemental analyses, FT-IR, ¹H NMR spectroscopy, X-ray diffraction. A quantum-chemical calculation was performed using the CNDO method. In the title compound, C₁₈H₁₁ClN₂O₃S₂, the crystal structure is stabilized by intermolecular hydrogen bonds (C–H···O=C) to form centrosymmetric R₂² R_{2}^{2} (16) dimers and the C–H···O, O–H···N, and C–H···N interactions generating the graph set motifs R₂² R_{2}^{2} (9) and R₂² R_{2}^{2} (22).     

Spectroscopic Studies and Crystal Structure of (<Emphasis Type="Italic">Z</Emphasis>)-6-[(2-hydroxyphenylamino)methylene]-2-methoxycyclohexa-2,4-dienone

Abstract  The Schiff base (Z)-6-[(2-hydroxyphenylamino)methylene]-2-methoxycyclohexa-2,4-dienone has been synthesized from the reaction of 2-aminophenol with 2-hydroxy-3-methoxybenzaldehyde. The title compound has been characterized by elemental analysis, FT-IR, ¹H-NMR, ¹³C-NMR and UV–Visible techniques. The structure of the title compound also was determined crystallographically. The crystal structure has been solved by direct methods and refined by full-matrix least squares. The title compound crystallize in the monoclinic space group P2₁/c with a = 10.438(1), b = 8.851(1), c = 12.746(1) ?, β = 95.72(1)°, V = 1171.7(2) ?³, D _x  = 1.379 g cm⁻³, respectively (R1 = 0.0522 and wR2 = 0.126 for 1442 reflections [I > 2σ(I)]). Index Abstract   N-salicylideneaniline derivatives have been shown to exist as tautomeric forms due to intramolecular proton shifts between the phenol-oxygen and the imine-nitrogen, via intramolecular hydrogen bonding O–H···N or O···H–N.      

Crystal Structure of <Emphasis Type="Italic">N</Emphasis>-(2-Pyridylmethylene)benzene-1,4-diamine

Abstract  

The crystal structure of amino containing Schiff base, N-(2-pyridylmethylene)benzene-1,4-diamine, was determined via X-ray diffraction analysis. The title compound crystallizes in orthorhombic system, space group Pc2 ₁ n, with unit cell dimensions a = 5.8945(6), b = 11.9233 (10), c = 14.5356 (16) ?, V = 1021.59 (18) ?³, Z = 4. The molecules are linked by intermolecular N–H···N hydrogen bonds to form supramolecular sheets along with the bc crystallographic plane. The crystal structure is further stabilized by C–H···π stacking interactions.     

Synthesis,Characterization and Antibacterial Activity of <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">N</Emphasis>-Acetic Acid-yl-Phthalimide-5-yl) Maleamic Acid Dihydrate

Abstract  

The compound N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid (C₁₄H₁₀N₂O₇, M _r  = 318) was synthesized and its structure was characterized by elemental analysis, ¹H NMR and IR spectra. The single crystal of the title compound (C₁₄H₁₄N₂O₉, M _r  = 354.27) was cultured and its structure was determined by single crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 14.3859(19), b = 12.5835(18), c = 8.6934(15) ?, β = 102.824(2)°, V = 1534.5(4) ?³, Z = 4, D _c  = 1.534 g cm⁻³, μ(Mo Kα) = 0.131 mm⁻¹, F(000) = 736. The final refinement gave R = 0.0652, wR(F ²) = 0.1239 for 2,703 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the asymmetric unit of the title compound contains one N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid molecule and two water molecules. One of the two water molecules is disordered. The phthalimide group is essentially planar. The crystal structure of the title compound is stabilized by N–H…O and O–H…O hydrogen bonds interactions. The compound N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid possesses moderate antibacterial activity.     

Crystal Structure and Spectroscopic Properties of <Emphasis Type="Italic">trans</Emphasis>-Dibromobis(1,2-ethanediamine)chromium(III) Perchlorate

Abstract  

The crystal structure of trans-[Cr(en)₂Br₂]ClO₄ (en = 1,2-ethanediamine) has been determined by a single-crystal X-ray diffraction study at 150 K. The complex crystallizes in the space group P[`1] P\overline{1} of the triclinic system with two mononuclear formula units in a cell of dimensions a = 6.853(4), b = 8.109(5), c = 12.475(8) ?, α = 81.006(10)°, β = 77.005(10)° and γ = 74.981(10)°. The Cr atom is in a slightly distorted octahedral environment, coordinated by four nitrogen atoms of two en ligands and two bromine atoms in trans axial positions. The mean Cr–N(en) and Cr–Br bond lengths are 2.079(3) and 2.4743(10)?, respectively. The five-membered rings are in stable gauche conformations with N1–Cr1–N2 and N3–Cr2–N4 angles of 82.81(11)° and 83.67(11)°, respectively. The crystal packing is stabilized by a network of N–H···O and N–H···Br hydrogen bonds. The infrared and electronic absorption spectra are consistent with the results of X-ray crystallography.     

Crystal Structure and Conformational Analysis of 4-[(<Emphasis Type="Italic">p</Emphasis>-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-Dimethylamino)Benzylidene]-2-Phenyloxazole-5-One

Abstract  

Molecular and crystal structure of 4-[(p-N,N-dimethylamino)benzylidene]-2-phenyloxazol-5-one, C₁₈H₁₆N₂O₂, have been determined by single crystal X-ray diffraction study. The title compound is monoclinic, with a = 12.1704(23) ?, b = 3.9810(5) ?, c = 30.9603(56) ?, β = 101.176(15)°, Z = 4, D _x = 1.32 g/cm³, μ(Mo Kα) = 0.087 mm⁻¹, and space group is P12₁/c1. The structure was solved by direct methods and refined to a final R = 0.047 for 3166 reflections with I > 2σ(I). The crystal structure is stabilized by C–H⋯O and C–H⋯N type intra-molecular, C–H⋯O type inter-molecular interactions. To enlighten the flexibility and the geometric isomerism (E or Z) of the title compound, the selected torsion angle is varied from −180 to 180° in every 10° separately and molecular energy profile is calculated and analyzed.     

Synthesis and Crystal Structures of Methyl 3-(Benzoylamino)-6-methyl-2-oxo-2<Emphasis Type="Italic">H</Emphasis>-pyran-5-carboxylate and <Emphasis Type="Italic">N</Emphasis>-[5-(3,4-Dimethoxyphenyl)-6-methyl-2-oxo-2<Emphasis Type="Italic">H</Emphasis>-pyran-3-yl]benzamide

Abstract  

The compounds methyl 3-(benzoylamino)-6-methyl-2-oxo-2H-pyran-5-carboxylate (1), C₁₅H₁₃NO₅, and N-[5-(3,4-dimethoxyphenyl)-6-methyl-2-oxo-2H-pyran-3-yl]benzamide (2), C₂₁H₁₉NO₅, crystallize as a centrosymmetric hydrogen-bonded dimer facilitated by N–H···O interactions involving the amide and carbonyl moiety of the lactone group of adjacent molecules. Supramolecular aggregation in 1 is controlled by a combination of π–π interactions [centroid–centroid distance = 4.0745(11) ?] and weak C–H···O hydrogen bonding between the phenyl ring of the benzoylamino group and the carbonyl atom of the methoxycarbonyl group and in 2 by a combination of π–π interactions [centroid–centroid distance = 4.0699(8) and 4.1556(10) ?], weak C–H···O interactions between the methoxy substituents of the adjacent dimethoxyphenyl group and weak C–H··· π interactions.     

Synthesis,Spectroscopic Studies and X-ray Analysis of (<Emphasis Type="Italic">E</Emphasis>)-2-(2-Fluorophenyl)-3-(6-Nitrobenzo[d][1,3]dioxol-5-yl) Acrylic Acid

Abstract  

In the solid-state structure of the title compound, C₁₆H₁₀FNO₆, the configuration about the C=C double bond is E. The compound crystallized in the triclinic system, having space group P-1 with unit cell dimensions a = 5.829(10) ?, b = 8.801(16) ?, c = 13.543(3) ?, α = 87.753(15)°, β = 81.945(15)°, γ = 86.342(14)°. The structure of the molecule is V-shaped and in the crystal the molecules are linked to form inversion dimers connected by pairs of C–H···O hydrogen bonds.     

Synthesis,Crystal Structure and Thermal Properties of <Emphasis Type="Italic">N</Emphasis>-Acetyl-3-(2-furyl)-5-ferrocenyl-2-pyrazoline and <Emphasis Type="Italic">N</Emphasis>-Acetyl-3-(2-thienyl)-5-ferrocenyl-2-pyrazoline

Abstract  

Two novel ferrocenyl substituted N-acetyl-2-pyrazolines, N-acetyl-3-(2-furyl)-5-ferrocenyl-2-pyrazoline (3) and N-acetyl-3-(2-thienyl)-5-ferrocenyl-2-pyrazoline (4), have been synthesized and characterized by FTIR, ¹H-NMR, ¹³C-NMR techniques, elemental analysis and X-ray structure analysis. Thermal properties of these compounds have been determined by TGA, DTA and DSC analysis. Compound 3 (C₁₉H₁₈N₂O₂Fe) crystallizes in the monoclinic space group P21/c and Z = 4, with a = 8.6970(4) ?, b = 18.4725(9) ?, c = 11.0041(5) ?, β = 110.942(3)°. Compound 4 (C₁₉H₁₈N₂OSFe) crystallizes in the orthorhombic space group Fdd2 and Z = 16, with a = 84.242(2) ?, b = 13.5416(5) ?, c = 5.9405(2) ?, β = 90°. In terms of crystal packing, each compound shows different molecular arrangement, which are stabilized by C–H···O intermolecular weak hydrogen bonds, and/or C–H···π interactions.     

Synthesis and Crystal Structure of 4-Methyl-6H-pyrido[3,2,1-<Emphasis Type="Italic">jk</Emphasis>]carbazol-6-one

Abstract  The synthesis, NMR and X-ray structure of 4-methyl-6H-pyrido[3,2,1-jk]carbazol-6-one—a potential DNA intercalator are reported. The compound crystallizes in the orthorhombic Pbca space group with unit cell parameters: a = 7.775(8), b = 15.113(7), c = 19.849(7) ?, V = 2332.8(3) ?³, Mr = 233.26 and Z = 8. In the three-dimensional arrangement of the molecules no classical hydrogen bonds were found; weak π···π and C–H···O interactions are responsible for the packing of the molecules in the crystal structure. Index Abstract  In the three-dimensional arrangement of the title compound no classical hydrogen bonds were found; weak π···π and C–H···O interactions are responsible for the packing of the molecules in the crystal structure.      

<Emphasis Type="Italic">Mangifera indica</Emphasis>: Crystal Structures of Two Cycloartane Type Triterpenoids Present in the Bark

Abstract  

Cycloart-23-ene-3-oxo-26-oic acid or Mangiferolic acid (C₃₀H₄₈O₃), compound 1 and Cycloart-23-ene-3β,25-diol (C₃₀H₅₀O₂) compound 2, were isolated from the bark of Mangifera indica. The structures of both compounds 1 and 2 were established by spectral and X-ray diffraction studies. Compound 1 crystallizes in the monoclinic space group P2₁ with unit cell parameters a = 8.416(1), b = 20.638(2), c = 17.203(2) Å, β = 91.779(2)°, Z = 2. Compound 2 crystallizes in the monoclinic space group C 2 with unit cell parameters a = 33.824(9), b = 7.413(2), c = 11.136(3) Å, β = 98.347(4)°, Z = 4. Both structures (1 and 2) were solved by direct methods and refined to R = 0.0511 and 0.0588, respectively. For compound 1, there are two independent molecules (1A and 1B) per asymmetric unit and one disordered trichloride methane molecule. For compound 2, there is positional disorder of the side chain at C17 beginning from C23 up to C27. All the rings of both steroid skeletons are trans connected. For structures 1A, 1B and 2, the six-membered rings A, B and C have a deformed chair, deformed chair and sofa conformations. The five-membered rings D adopt a half-chair conformation. In structure 1, there are two types of hydrogen bonds, the first type, the molecules 1A and 1B are linked by pairs of O(3A)–H···O(1B) and O3B H3B···O1A hydrogen bonds. In addition, both O(1A)–H and O(1B)–H hydroxyl groups participate in a second type of hydrogen bond involving the atoms O(2A) and O(2B) of adjacent molecules, respectively. In structure 2, there is a characteristic pattern observed in packing diagram is that both hydroxyl groups (O1–H and O2–H) participate as hydrogen bond donors and acceptors. In both structures 1 and 2, the hydrophobic part of the steroid nucleus is stabilized by C–H···O interactions and van der Waals forces.