organic compounds
(3aR,6R)-3,3,6-Trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide
aLaboratoire de Synthèse Organique et Physico-Chimie Moléculaire, Département de Chimie, Faculté, des Sciences, Semlalia BP 2390, Marrakech 40001, Morocco, bInstitut de Chimie Moléculaire de Reims, CNRS UMR 7312 Bât. Europol'Agro, Moulin de la Housse UFR Sciences, BP 1039–51687 Reims Cédex 2, France, and cLaboratoire de Chimie des Substances Naturelles, "Unité Associé au CNRST (URAC16)", Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco
*Correspondence e-mail: berraho@uca.ac.ma
The title compound, C11H19N3S, was prepared by the reaction of (R)-pulegone with thiosemicarbazide in acidic medium, using ethanol as solvent. The molecule is built up from fused six and five-membered rings. The six-membered ring adopts a chair conformation, while the five-membered ring displays an with the dimethyl-substituted C atom as the flap. The dihedral angle between the mean planes of the two rings is 20.35 (6)°. In the crystal, molecules are linked by N—H⋯N and N—H⋯S hydrogen bonds into chains running parallel to [100].
Keywords: crystal structure; indazole; carbothioamide; thiosemicarbazide; N—H⋯N hydrogen bonds; N—H⋯S hydrogen bonds.
CCDC reference: 1472696
Structure description
In recent years, the synthesis of heterocyclic systems containing nitrogen has attracted great interest because of their broad spectrum of pharmacological activities. In particular, indazole is a crucial heterocyclic skeleton present in a wide variety of drugs, many natural products and biologically active compounds (Gautam et al., 2015). Compounds containing the indazole skeleton are known to display a broad spectrum of potent pharmacological activities including anti-inflammatory (Rosati et al., 2007), anti-depressant (Bailey et al., 1985), anticancer (De Lena et al., 2001), antituberculosis (Guo et al., 2010) and antimicrobial activities (Ali et al., 2012). The therapeutic usefulness of these heterocyclic systems prompted us to prepare a new substituted 2H-indazole from a naturally occurring monoterpene. The title compound (3aR,6R)-3,3,6-trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide was prepared by the reaction of (R)-pulegone with thiosemicarbazide in acidic medium, using ethanol as solvent. The resulting product obtained as diastereomeric mixture, was then crystallized from ethanol to give the new compound as white monocrystals.
The title molecule, Fig. 1, contains a fused ring system and a carbothioamide group as a substituent to the pyrazolidine ring. The six-membered ring (C1/C7/C8/C19—C12) has a chair conformation as indicated by puckering parameters QT = 0.5218 (16) Å, θ = 16.11 (18) and φ2 = 199.40 (16)°. The pyrazolidine ring (N1/N2/C1/C7/C14) adopts an with atom C14 as the flap; deviating by 0.341 (1) Å from the mean plane through the other four atoms in the ring.
In the crystal, molecules are linked by N—H⋯N and N—H⋯S hydrogen bonds into chains running parallel to [100] (Table 1 and Fig. 2).
|
Owing to the presence of the S atom, the et al., 2013), as C3a(R) and C6(R).
could be fully confirmed, by refining the (ParsonsSynthesis and crystallization
A hot ethanolic solution containing equimolar quantities of thiosemicarbazide and (R)-pulegone with a few drops of concentrated HCl was heated under reflux. The progress of the reaction was monitored by TLC. After the completion of the reaction, the solvent was evaporated under reduced pressure and the crude product was purified by on silica gel (230–400 mesh) using hexane/ethyl acetate (95:5) as The pure indazolic product was obtained in 64% yield as a diastereomeric mixture. Slow evaporation from an ethanolic solution of the title compound gave crystals of the title compound, suitable for X-ray crystallographic analysis.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1472696
10.1107/S2414314616005733/su4023sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2414314616005733/su4023Isup2.hkl
Supporting information file. DOI: 10.1107/S2414314616005733/su4023Isup3.cml
A hot ethanolic solution containing equimolar quantities of thiosemicarbazide and (R)-pulegone with a few drops of concentrated HCl was heated under reflux. The progress of the reaction was monitored by TLC. After the completion of the reaction, the solvent was evaporated under reduced pressure and the crude product was purified by
on silica gel (230–400 mesh) using hexane/ethyl acetate (95:5) as The pure indazolic product was obtained in 64% yield as a diastereomeric mixture. Slow evaporation from an ethanolic solution of the title compound gave crystals of the title compound, suitable for X-ray crystallographic analysis.In recent years, the synthesis of heterocyclic systems containing nitrogen has attracted great interest because of their broad spectrum of pharmacological activities. In particular, indazole is a crucial heterocyclic skeleton present in a wide variety of drugs, many natural products and biologically active compounds (Gautam et al., 2015). Compounds containing the indazole skeleton are known to display a broad spectrum of potent pharmacological activities including anti-inflammatory (Rosati et al., 2007), anti-depressant (Bailey et al., 1985), anticancer (De Lena et al., 2001), antituberculosis (Guo et al., 2010) and antimicrobial activities (Ali et al., 2012). The therapeutic usefulness of these heterocyclic systems prompted us to prepare a new substituted 2H-indazole from a naturally occurring monoterpene. The title compound (3aR,6R)-3,3,6-trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide was prepared by the reaction of (R)-pulegone with thiosemicarbazide in acidic medium, using ethanol as solvent. The resulting product obtained as diastereomeric mixture, was then crystallized from ethanol to give the new compound as white monocrystals. The structure of this new product was confirmed by its single-crystal X-ray structure.
The title molecule, Fig. 1, contains a fused ring system and a carbothioamide group as a substituent to the pyrazolidine ring. The six-membered ring (C1/C7/C8/C19—C12) has a chair conformation as indicated by puckering parameters QT = 0.5218 (16) Å, θ = 16.11 (18) and φ2 = 199.40 (16)°. The pyrazolidine ring (N1/N2/C1/C7/C14) adopts an with atom C14 as the flap; deviating by 0.341 (1) Å from the mean plane through the other four atoms in the ring.
In the crystal, molecules are linked by N—H···N and N—H···S hydrogen bonds into chains running parallel to [100] (Table 1 and Fig. 2).
Owing to the presence of the S atom, the
could be fully confirmed, by refining the (Parsons et al., 2013), as C3a(R) and C6(R).Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).Fig. 1. Molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level. | |
Fig. 2. Partial crystal packing view along the c axis of the title compound. The N—H···N and N—H···S hydrogen bonds (dashed lines; Table 1) indicate the formation of a chain parallel to the a axis. H atoms not involved in hydrogen bonding have been omitted for clarity. |
C11H19N3S | Dx = 1.274 Mg m−3 |
Mr = 225.35 | Cu Kα radiation, λ = 1.5418 Å |
Orthorhombic, P212121 | Cell parameters from 17550 reflections |
a = 7.957 (5) Å | θ = 5.2–72.9° |
b = 10.796 (5) Å | µ = 2.21 mm−1 |
c = 13.673 (5) Å | T = 100 K |
V = 1174.6 (10) Å3 | Prismatic, colourless |
Z = 4 | 0.24 × 0.2 × 0.15 mm |
F(000) = 488 |
Bruker APEXII CCD diffractometer | 2315 independent reflections |
Radiation source: microsource | 2270 reflections with I > 2σ(I) |
Multi-layer mirror monochromator | Rint = 0.027 |
φ and ω scans | θmax = 72.2°, θmin = 5.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −9→9 |
Tmin = 0.618, Tmax = 0.718 | k = −12→13 |
17550 measured reflections | l = −16→16 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.021 | H-atom parameters constrained |
wR(F2) = 0.054 | w = 1/[σ2(Fo2) + (0.0309P)2 + 0.2126P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max = 0.001 |
2315 reflections | Δρmax = 0.22 e Å−3 |
140 parameters | Δρmin = −0.17 e Å−3 |
0 restraints | Absolute structure: Parsons et al. (2013), 972 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.028 (12) |
C11H19N3S | V = 1174.6 (10) Å3 |
Mr = 225.35 | Z = 4 |
Orthorhombic, P212121 | Cu Kα radiation |
a = 7.957 (5) Å | µ = 2.21 mm−1 |
b = 10.796 (5) Å | T = 100 K |
c = 13.673 (5) Å | 0.24 × 0.2 × 0.15 mm |
Bruker APEXII CCD diffractometer | 2315 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2270 reflections with I > 2σ(I) |
Tmin = 0.618, Tmax = 0.718 | Rint = 0.027 |
17550 measured reflections |
R[F2 > 2σ(F2)] = 0.021 | H-atom parameters constrained |
wR(F2) = 0.054 | Δρmax = 0.22 e Å−3 |
S = 1.06 | Δρmin = −0.17 e Å−3 |
2315 reflections | Absolute structure: Parsons et al. (2013), 972 Friedel pairs |
140 parameters | Absolute structure parameter: 0.028 (12) |
0 restraints |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.15695 (3) | 0.04077 (2) | 0.529496 (19) | 0.01460 (8) | |
C1 | 0.68856 (13) | 0.02162 (11) | 0.35481 (8) | 0.0111 (2) | |
N2 | 0.45543 (12) | 0.03660 (9) | 0.43699 (7) | 0.01126 (18) | |
N1 | 0.59405 (12) | 0.10135 (9) | 0.39659 (7) | 0.01179 (19) | |
C4 | 0.33782 (15) | 0.10291 (10) | 0.48530 (7) | 0.0117 (2) | |
N3 | 0.37036 (13) | 0.22324 (9) | 0.49959 (7) | 0.0167 (2) | |
H3A | 0.4626 | 0.2548 | 0.4784 | 0.020* | |
H3B | 0.2990 | 0.2690 | 0.5300 | 0.020* | |
C6 | 0.31991 (15) | −0.10083 (12) | 0.31667 (9) | 0.0171 (2) | |
H6A | 0.2100 | −0.0815 | 0.3413 | 0.026* | |
H6B | 0.3194 | −0.1827 | 0.2893 | 0.026* | |
H6C | 0.3503 | −0.0421 | 0.2670 | 0.026* | |
C7 | 0.63141 (14) | −0.10999 (10) | 0.36496 (8) | 0.0117 (2) | |
H7 | 0.6947 | −0.1462 | 0.4194 | 0.014* | |
C8 | 0.66596 (16) | −0.19039 (10) | 0.27468 (9) | 0.0168 (2) | |
H8A | 0.5851 | −0.1713 | 0.2238 | 0.020* | |
H8B | 0.6542 | −0.2772 | 0.2916 | 0.020* | |
C9 | 0.40770 (15) | −0.18861 (10) | 0.48000 (9) | 0.0167 (2) | |
H9A | 0.4661 | −0.1662 | 0.5388 | 0.025* | |
H9B | 0.4432 | −0.2695 | 0.4593 | 0.025* | |
H9C | 0.2889 | −0.1894 | 0.4922 | 0.025* | |
C10 | 0.87482 (14) | −0.02785 (11) | 0.21395 (8) | 0.0148 (2) | |
H10 | 0.9909 | −0.0184 | 0.1912 | 0.018* | |
C11 | 0.85262 (14) | 0.05119 (10) | 0.30711 (8) | 0.0137 (2) | |
H11A | 0.9439 | 0.0344 | 0.3523 | 0.016* | |
H11B | 0.8561 | 0.1384 | 0.2902 | 0.016* | |
C12 | 0.84475 (17) | −0.16553 (11) | 0.23718 (9) | 0.0176 (2) | |
H12A | 0.8640 | −0.2141 | 0.1786 | 0.021* | |
H12B | 0.9250 | −0.1922 | 0.2862 | 0.021* | |
C13 | 0.75792 (16) | 0.01904 (12) | 0.13366 (9) | 0.0191 (3) | |
H13A | 0.7674 | −0.0336 | 0.0773 | 0.029* | |
H13B | 0.7887 | 0.1021 | 0.1162 | 0.029* | |
H13C | 0.6441 | 0.0181 | 0.1569 | 0.029* | |
C14 | 0.44718 (14) | −0.09470 (10) | 0.40007 (8) | 0.0116 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.01105 (13) | 0.01600 (13) | 0.01675 (13) | −0.00067 (11) | 0.00364 (10) | −0.00051 (11) |
C1 | 0.0114 (5) | 0.0133 (5) | 0.0086 (5) | 0.0002 (4) | −0.0023 (4) | 0.0002 (4) |
N2 | 0.0104 (4) | 0.0093 (4) | 0.0141 (4) | −0.0019 (4) | 0.0017 (3) | 0.0004 (4) |
N1 | 0.0098 (4) | 0.0138 (4) | 0.0118 (4) | −0.0025 (4) | 0.0008 (3) | 0.0007 (4) |
C4 | 0.0118 (5) | 0.0136 (5) | 0.0098 (5) | 0.0015 (4) | −0.0011 (4) | 0.0013 (4) |
N3 | 0.0140 (5) | 0.0134 (5) | 0.0228 (5) | 0.0001 (4) | 0.0053 (4) | −0.0047 (4) |
C6 | 0.0134 (6) | 0.0202 (6) | 0.0178 (5) | 0.0002 (5) | −0.0018 (5) | −0.0035 (5) |
C7 | 0.0105 (5) | 0.0121 (5) | 0.0125 (5) | 0.0008 (4) | 0.0001 (4) | 0.0012 (4) |
C8 | 0.0183 (6) | 0.0123 (5) | 0.0197 (5) | 0.0000 (5) | 0.0035 (5) | −0.0034 (4) |
C9 | 0.0172 (5) | 0.0128 (5) | 0.0200 (6) | −0.0022 (4) | 0.0020 (5) | 0.0034 (5) |
C10 | 0.0108 (5) | 0.0195 (6) | 0.0141 (5) | 0.0014 (5) | 0.0029 (4) | −0.0009 (5) |
C11 | 0.0100 (5) | 0.0164 (5) | 0.0148 (5) | −0.0015 (5) | 0.0007 (4) | −0.0004 (4) |
C12 | 0.0163 (6) | 0.0175 (5) | 0.0189 (5) | 0.0045 (5) | 0.0032 (5) | −0.0029 (4) |
C13 | 0.0182 (6) | 0.0260 (7) | 0.0131 (5) | 0.0003 (5) | 0.0011 (4) | 0.0014 (5) |
C14 | 0.0120 (5) | 0.0093 (5) | 0.0134 (5) | 0.0002 (4) | 0.0002 (4) | −0.0010 (4) |
S1—C4 | 1.6990 (14) | C8—H8A | 0.9700 |
C1—N1 | 1.2778 (16) | C8—H8B | 0.9700 |
C1—C11 | 1.4938 (16) | C9—C14 | 1.5235 (16) |
C1—C7 | 1.4983 (16) | C9—H9A | 0.9600 |
N2—C4 | 1.3507 (15) | C9—H9B | 0.9600 |
N2—N1 | 1.4180 (14) | C9—H9C | 0.9600 |
N2—C14 | 1.5062 (15) | C10—C13 | 1.5254 (16) |
C4—N3 | 1.3390 (15) | C10—C12 | 1.5387 (18) |
N3—H3A | 0.8600 | C10—C11 | 1.5433 (15) |
N3—H3B | 0.8600 | C10—H10 | 0.9800 |
C6—C14 | 1.5265 (17) | C11—H11A | 0.9700 |
C6—H6A | 0.9600 | C11—H11B | 0.9700 |
C6—H6B | 0.9600 | C12—H12A | 0.9700 |
C6—H6C | 0.9600 | C12—H12B | 0.9700 |
C7—C8 | 1.5339 (15) | C13—H13A | 0.9600 |
C7—C14 | 1.5513 (17) | C13—H13B | 0.9600 |
C7—H7 | 0.9800 | C13—H13C | 0.9600 |
C8—C12 | 1.5358 (19) | ||
N1—C1—C11 | 124.44 (11) | C14—C9—H9C | 109.5 |
N1—C1—C7 | 114.76 (10) | H9A—C9—H9C | 109.5 |
C11—C1—C7 | 120.55 (10) | H9B—C9—H9C | 109.5 |
C4—N2—N1 | 117.92 (10) | C13—C10—C12 | 111.98 (10) |
C4—N2—C14 | 129.24 (9) | C13—C10—C11 | 109.92 (10) |
N1—N2—C14 | 111.55 (8) | C12—C10—C11 | 110.24 (9) |
C1—N1—N2 | 107.45 (10) | C13—C10—H10 | 108.2 |
N3—C4—N2 | 116.85 (10) | C12—C10—H10 | 108.2 |
N3—C4—S1 | 119.67 (9) | C11—C10—H10 | 108.2 |
N2—C4—S1 | 123.47 (9) | C1—C11—C10 | 110.02 (9) |
C4—N3—H3A | 120.0 | C1—C11—H11A | 109.7 |
C4—N3—H3B | 120.0 | C10—C11—H11A | 109.7 |
H3A—N3—H3B | 120.0 | C1—C11—H11B | 109.7 |
C14—C6—H6A | 109.5 | C10—C11—H11B | 109.7 |
C14—C6—H6B | 109.5 | H11A—C11—H11B | 108.2 |
H6A—C6—H6B | 109.5 | C8—C12—C10 | 112.45 (10) |
C14—C6—H6C | 109.5 | C8—C12—H12A | 109.1 |
H6A—C6—H6C | 109.5 | C10—C12—H12A | 109.1 |
H6B—C6—H6C | 109.5 | C8—C12—H12B | 109.1 |
C1—C7—C8 | 114.07 (9) | C10—C12—H12B | 109.1 |
C1—C7—C14 | 102.39 (9) | H12A—C12—H12B | 107.8 |
C8—C7—C14 | 118.59 (10) | C10—C13—H13A | 109.5 |
C1—C7—H7 | 107.0 | C10—C13—H13B | 109.5 |
C8—C7—H7 | 107.0 | H13A—C13—H13B | 109.5 |
C14—C7—H7 | 107.0 | C10—C13—H13C | 109.5 |
C7—C8—C12 | 109.62 (10) | H13A—C13—H13C | 109.5 |
C7—C8—H8A | 109.7 | H13B—C13—H13C | 109.5 |
C12—C8—H8A | 109.7 | N2—C14—C9 | 113.26 (9) |
C7—C8—H8B | 109.7 | N2—C14—C6 | 108.67 (9) |
C12—C8—H8B | 109.7 | C9—C14—C6 | 111.73 (10) |
H8A—C8—H8B | 108.2 | N2—C14—C7 | 99.36 (8) |
C14—C9—H9A | 109.5 | C9—C14—C7 | 110.25 (9) |
C14—C9—H9B | 109.5 | C6—C14—C7 | 113.02 (10) |
H9A—C9—H9B | 109.5 |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3B···N1i | 0.86 | 2.37 | 3.230 (3) | 176 |
N3—H3A···S1ii | 0.86 | 2.70 | 3.442 (3) | 146 |
Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x+1/2, −y+1/2, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3B···N1i | 0.86 | 2.37 | 3.230 (3) | 176 |
N3—H3A···S1ii | 0.86 | 2.70 | 3.442 (3) | 146 |
Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x+1/2, −y+1/2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C11H19N3S |
Mr | 225.35 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 100 |
a, b, c (Å) | 7.957 (5), 10.796 (5), 13.673 (5) |
V (Å3) | 1174.6 (10) |
Z | 4 |
Radiation type | Cu Kα |
µ (mm−1) | 2.21 |
Crystal size (mm) | 0.24 × 0.2 × 0.15 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.618, 0.718 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17550, 2315, 2270 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.618 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.021, 0.054, 1.06 |
No. of reflections | 2315 |
No. of parameters | 140 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.17 |
Absolute structure | Parsons et al. (2013), 972 Friedel pairs |
Absolute structure parameter | 0.028 (12) |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
Acknowledgements
The authors thank Pr. Auhmani Abdelouhed as laboratory manager.
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