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Acta Crystallographica Section E: Crystallographic Communications logoLink to Acta Crystallographica Section E: Crystallographic Communications
. 2018 Jan 1;74(Pt 1):62–64. doi: 10.1107/S2056989017017935

Crystal structure of 6,7-de­hydro­royleanone isolated from Taxodium distichum (L.) Rich.

Li Chen a, Xinhua Ma a, ShiHao Deng a, XinZhou Yang a,*, Ping Song b,*
PMCID: PMC5778487  PMID: 29416893

The crystal structure features two O—H⋯O hydrogen bonds, forming chains along the [010] direction.

Keywords: crystal structure; 6,7-de­hydro­royleanone; Taxodium distichum (L.) Rich

Abstract

The title compound, 6,7-de­hydro­royleanone, C20H26O3 [systematic name: (4bS)-3-hy­droxy-2-isopropyl-4b,8,8-trimethyl-4b,5,6,7,8,8a-hexa­hydro­phenanthrene-1,4-dione] was isolated from Taxodium distichum (L.) Rich. The compound crystallizes in the space group P21. The crystal structure features two O—H⋯O hydrogen bonds, forming chains along the [010] direction.

Chemical context  

Taxodium distichum (L.) Rich. is a tree native to North America that can grow to 25 m in height (Ogunwande et al., 2007). Its leaves and seeds are used for the treatment of malaria and liver disease (Kupchan et al., 1968). Previous studies revealed that it contains multiple compounds such as diterpenes (Kusumoto et al., 2010), flavonoids (Zaghloul et al., 2008), proanthocyanidins (Stafford & Lester, 1986), lignins (Logan & Thomas, 1985), sterols and fatty acids (Geiger & de Groot-Pfleiderer, 1979). A detailed phytochemical investigation of a petroleum ether extract of the seeds of Taxodium distichum (L.) Rich. led to the isolation of the title compound 6,7-de­hydro­royleanone. Herein we present the crystal structure of 6,7-de­hydro­royleanone, which was undertaken in order to establish unambiguously the stereochemical features of this natural compound.graphic file with name e-74-00062-scheme1.jpg

Structural commentary  

The mol­ecular structure of the title compound is shown in Fig. 1. The title compound belongs to the class of abietane-type diterpenes and the structure contains two ketone groups at C14 and C17 and three double bonds located between atoms C10 and C11, C12 and C13, C15 and C16. The torsion angles C17—C12—C13—C1 [176.8 (2)°], C11—C12—C13—C14 [168.7 (3)°], C6—C1—C2—C10 [171.6 (3)°] and C13—C1—C2—C3 [−173.4 (3)°] describe the geometry at the junctions of the three rings. An intra­molecular O2—H2A⋯O1 hydrogen bond (Table 1) stabilizes the mol­ecular conformation.

Figure 1.

Figure 1

The mol­ecular structure of the title compound, with the atom labelling and 50% probability displacement ellipsoids. The intra­molecular O—H⋯O hydrogen bond (see Table 1) is shown as a red dashed line.

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2A⋯O1 0.82 (6) 2.03 (5) 2.607 (3) 128 (5)
O2—H2A⋯O3i 0.82 (6) 2.53 (6) 3.160 (3) 135 (5)
C11—H11⋯O1ii 0.93 2.37 3.290 (3) 173 (5)

Symmetry codes: (i) Inline graphic; (ii) Inline graphic.

Supra­molecular features  

In the crystal, O2—H2A⋯O3i and C11—H11⋯O1i hydrogen bonds link the mol­ecules, forming chains along [010] (Table 1 and Fig. 2).

Figure 2.

Figure 2

Part of the crystal structure of the title compound, with hydrogen bonds (see Table 1) shown as dashed lines.

Database survey  

A search of the Cambridge Structural Database (CSD, Version 5.27, last update Feb 2017; Groom et al., 2016) yielded the compound royleanone (HACGUN01; Fun et al., 2011), which has a similar structure to the title compound but without the double bond between C10 and C11.

Synthesis and crystallization  

The title compound was isolated from the seeds of Taxodium distichum (L.) Rich. collected in Xining, China, in April 2015 (SC0185). The air-dried seeds of Taxodium distichum (1.1 kg) were extracted with 95% EtOH and then partitioned successively with petroleum ether (PE), ethyl acetate (EtOAc) and n-butyl alcohol (n-BuOH) to give a PE extract (30 g), an EtOAc extract (50 g) and an n-BuOH extract (68 g). The PE extract (30 g) was subjected to normal-phase silica-gel column chromatography (300–400 mesh) with a gradient solvent system of petroleum ether–ethyl acetate (1:0-0:1, v/v, containing 0.1% formic acid) to give ten major fractions, denoted F1–F10. F7 (2.8 g) was sequentially subjected to Sephadex-LH20 gel column chromatography (CH2Cl2–MeOH, 3:1, v/v, containing 0.1% formic acid) to give four major fractions F7.1–F7.4. F7.3 was purified by semi-preparative HPLC (CNCH3/H2O, 20:80→100:0, 40 min, containing 0.1% formic acid in both phases) to give an orange solid, which was recrystallized from a solvent mix of CH2Cl2–MeOH (5:1) affording orange block-like crystals suitable for X-ray diffraction analysis. For the 1H and 13C NMR data of 6,7-de­hydro­royleanone, see Chang et al. (2001).

Refinement  

Crystal data, data collection and structure refinement details are summarized in Table 2. C-bound H atoms were positioned with idealized geometry and refined isotropically using a riding model with C—H = 0.94–0.99 Å and U iso(H) = 1.5U eq(C) for methyl H atoms and 1.2U eq(C) for all others. The OH hydrogen atom was refined freely with U iso(H) = 1.5U eq(O).

Table 2. Experimental details.

Crystal data
Chemical formula C20H26O3
M r 314.41
Crystal system, space group Monoclinic, P21
Temperature (K) 296
a, b, c (Å) 10.4348 (17), 7.6726 (13), 10.8210 (18)
β (°) 97.773 (3)
V3) 858.4 (2)
Z 2
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.3 × 0.2 × 0.2
 
Data collection
Diffractometer Bruker P4
No. of measured, independent and observed [I > 2σ(I)] reflections 6718, 3416, 2980
R int 0.022
(sin θ/λ)max−1) 0.625
 
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S 0.047, 0.143, 1.08
No. of reflections 3416
No. of parameters 216
No. of restraints 1
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.27, −0.18

Computer programs: APEX2 and SAINT (Bruker, 2007), SHELXT (Sheldrick, 2015a ), SHELXL2016 (Sheldrick, 2015b ) and OLEX2 (Dolomanov et al., 2009).

Supplementary Material

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989017017935/qm2118sup1.cif

e-74-00062-sup1.cif (275.2KB, cif)

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989017017935/qm2118Isup2.hkl

e-74-00062-Isup2.hkl (272.6KB, hkl)

Supporting information file. DOI: 10.1107/S2056989017017935/qm2118Isup3.cdx

Supporting information file. DOI: 10.1107/S2056989017017935/qm2118Isup4.cml

CCDC reference: 1551127

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Crystal data

C20H26O3 F(000) = 340
Mr = 314.41 Dx = 1.216 Mg m3
Monoclinic, P21 Mo Kα radiation, λ = 0.71073 Å
a = 10.4348 (17) Å Cell parameters from 2696 reflections
b = 7.6726 (13) Å θ = 2.6–27.3°
c = 10.8210 (18) Å µ = 0.08 mm1
β = 97.773 (3)° T = 296 K
V = 858.4 (2) Å3 Block, orange
Z = 2 0.3 × 0.2 × 0.2 mm

Data collection

Bruker P4 diffractometer θmax = 26.4°, θmin = 1.9°
φ and ω scans h = −13→12
6718 measured reflections k = −9→9
3416 independent reflections l = −13→13
2980 reflections with I > 2σ(I) 1 standard reflections every 300 reflections
Rint = 0.022 intensity decay: 1%

Refinement

Refinement on F2 1 restraint
Least-squares matrix: full Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.047 H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.143 w = 1/[σ2(Fo2) + (0.0865P)2 + 0.0799P] where P = (Fo2 + 2Fc2)/3
S = 1.08 (Δ/σ)max = 0.003
3416 reflections Δρmax = 0.27 e Å3
216 parameters Δρmin = −0.18 e Å3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

x y z Uiso*/Ueq
C1 0.3123 (3) 0.9175 (4) 0.1442 (2) 0.0325 (6)
C2 0.4090 (3) 1.0711 (4) 0.1650 (3) 0.0400 (7)
H2 0.454767 1.067917 0.091644 0.048*
C3 0.5186 (3) 1.0545 (5) 0.2774 (3) 0.0471 (8)
C4 0.5860 (4) 0.8794 (7) 0.2667 (4) 0.0712 (13)
H4A 0.633484 0.882840 0.195663 0.085*
H4B 0.647861 0.861196 0.340907 0.085*
C5 0.4925 (6) 0.7270 (6) 0.2515 (5) 0.098 (2)
H5A 0.450167 0.716784 0.325687 0.117*
H5B 0.540153 0.620204 0.242845 0.117*
C6 0.3896 (4) 0.7501 (5) 0.1370 (4) 0.0696 (13)
H6A 0.431584 0.752332 0.062273 0.084*
H6B 0.331142 0.651222 0.130827 0.084*
C7 0.2214 (4) 0.9005 (8) 0.2443 (3) 0.0746 (14)
H7A 0.148629 0.829236 0.213057 0.112*
H7B 0.191762 1.014064 0.264675 0.112*
H7C 0.267276 0.847719 0.317782 0.112*
C8 0.4756 (5) 1.0761 (7) 0.4025 (4) 0.0797 (14)
H8A 0.427134 0.975447 0.421190 0.120*
H8B 0.422203 1.178020 0.402234 0.120*
H8C 0.549959 1.088847 0.464619 0.120*
C9 0.6187 (5) 1.1986 (9) 0.2651 (6) 0.106 (2)
H9A 0.581634 1.310139 0.279235 0.160*
H9B 0.643405 1.195624 0.182830 0.160*
H9C 0.693627 1.179893 0.325620 0.160*
C10 0.3398 (5) 1.2400 (6) 0.1542 (5) 0.0861 (17)
H10 0.356742 1.324207 0.216089 0.103*
C11 0.2507 (3) 1.2703 (4) 0.0517 (3) 0.0480 (8)
H11 0.222528 1.382398 0.029548 0.058*
C12 0.2011 (3) 1.1170 (4) −0.0221 (3) 0.0346 (6)
C13 0.2247 (3) 0.9533 (3) 0.0209 (2) 0.0312 (6)
C14 0.1516 (3) 0.8125 (4) −0.0477 (3) 0.0370 (6)
C15 0.0868 (3) 0.8459 (4) −0.1776 (3) 0.0376 (7)
C16 0.0709 (3) 1.0066 (4) −0.2261 (3) 0.0359 (6)
C17 0.1215 (3) 1.1519 (4) −0.1454 (3) 0.0346 (6)
C18 0.0096 (3) 1.0468 (5) −0.3588 (3) 0.0451 (7)
H18 0.001388 1.173803 −0.365603 0.054*
C19 0.0958 (4) 0.9899 (7) −0.4517 (3) 0.0680 (11)
H19A 0.177527 1.048720 −0.434859 0.102*
H19B 0.055809 1.018277 −0.534386 0.102*
H19C 0.109290 0.866270 −0.445188 0.102*
C20 −0.1270 (4) 0.9706 (7) −0.3885 (4) 0.0711 (12)
H20A −0.121950 0.845769 −0.390726 0.107*
H20B −0.166517 1.012984 −0.468077 0.107*
H20C −0.177917 1.005487 −0.325198 0.107*
O1 0.1376 (3) 0.6667 (3) −0.0048 (2) 0.0561 (7)
O2 0.0435 (3) 0.7012 (3) −0.2393 (2) 0.0521 (6)
H2A 0.058 (5) 0.628 (8) −0.184 (5) 0.078*
O3 0.1021 (2) 1.3039 (3) −0.1790 (2) 0.0497 (6)

Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23
C1 0.0388 (14) 0.0315 (15) 0.0263 (12) −0.0009 (12) 0.0013 (10) 0.0016 (10)
C2 0.0381 (14) 0.0392 (17) 0.0405 (14) −0.0066 (13) −0.0029 (11) 0.0027 (13)
C3 0.0432 (16) 0.0488 (19) 0.0448 (16) −0.0042 (15) −0.0108 (13) 0.0022 (15)
C4 0.060 (2) 0.086 (3) 0.060 (2) 0.027 (2) −0.0208 (18) −0.012 (2)
C5 0.119 (4) 0.047 (3) 0.105 (4) 0.026 (3) −0.070 (3) −0.010 (3)
C6 0.085 (3) 0.043 (2) 0.069 (2) 0.022 (2) −0.035 (2) −0.0170 (18)
C7 0.056 (2) 0.126 (4) 0.0416 (19) −0.030 (2) 0.0079 (16) 0.008 (2)
C8 0.082 (3) 0.101 (4) 0.050 (2) 0.002 (3) −0.0137 (19) −0.031 (2)
C9 0.074 (3) 0.113 (5) 0.116 (4) −0.049 (3) −0.047 (3) 0.047 (4)
C10 0.098 (3) 0.034 (2) 0.107 (4) −0.002 (2) −0.058 (3) −0.010 (2)
C11 0.0561 (18) 0.0279 (16) 0.0545 (19) −0.0007 (13) −0.0124 (15) −0.0005 (14)
C12 0.0351 (13) 0.0292 (14) 0.0383 (14) −0.0001 (11) 0.0009 (11) 0.0001 (12)
C13 0.0334 (13) 0.0278 (15) 0.0318 (13) −0.0006 (11) 0.0022 (10) 0.0009 (11)
C14 0.0433 (15) 0.0285 (16) 0.0377 (15) −0.0001 (12) 0.0003 (12) 0.0015 (12)
C15 0.0410 (14) 0.0318 (16) 0.0375 (15) −0.0029 (12) −0.0038 (12) −0.0037 (12)
C16 0.0352 (14) 0.0364 (16) 0.0348 (14) 0.0040 (11) 0.0000 (11) 0.0021 (12)
C17 0.0321 (13) 0.0309 (15) 0.0403 (15) 0.0017 (12) 0.0026 (11) 0.0016 (12)
C18 0.0541 (18) 0.0399 (18) 0.0372 (15) 0.0030 (15) −0.0087 (13) 0.0022 (13)
C19 0.084 (3) 0.083 (3) 0.0374 (16) 0.013 (2) 0.0072 (17) 0.0045 (19)
C20 0.058 (2) 0.072 (3) 0.074 (3) 0.002 (2) −0.025 (2) −0.002 (2)
O1 0.0790 (16) 0.0311 (12) 0.0532 (14) −0.0106 (11) −0.0091 (12) 0.0062 (10)
O2 0.0703 (15) 0.0339 (13) 0.0454 (12) −0.0065 (11) −0.0170 (11) −0.0030 (10)
O3 0.0576 (13) 0.0312 (12) 0.0554 (14) 0.0020 (10) −0.0102 (11) 0.0077 (10)

Geometric parameters (Å, º)

C1—C2 1.548 (4) C9—H9C 0.9600
C1—C6 1.525 (5) C10—H10 0.9300
C1—C7 1.538 (4) C10—C11 1.367 (5)
C1—C13 1.537 (4) C11—H11 0.9300
C2—H2 0.9800 C11—C12 1.475 (4)
C2—C3 1.558 (4) C12—C13 1.350 (4)
C2—C10 1.481 (6) C12—C17 1.497 (4)
C3—C4 1.528 (6) C13—C14 1.466 (4)
C3—C8 1.492 (5) C14—C15 1.497 (4)
C3—C9 1.539 (6) C14—O1 1.227 (4)
C4—H4A 0.9700 C15—C16 1.341 (4)
C4—H4B 0.9700 C15—O2 1.342 (4)
C4—C5 1.517 (8) C16—C17 1.470 (4)
C5—H5A 0.9700 C16—C18 1.522 (4)
C5—H5B 0.9700 C17—O3 1.230 (4)
C5—C6 1.536 (5) C18—H18 0.9800
C6—H6A 0.9700 C18—C19 1.501 (5)
C6—H6B 0.9700 C18—C20 1.534 (5)
C7—H7A 0.9600 C19—H19A 0.9600
C7—H7B 0.9600 C19—H19B 0.9600
C7—H7C 0.9600 C19—H19C 0.9600
C8—H8A 0.9600 C20—H20A 0.9600
C8—H8B 0.9600 C20—H20B 0.9600
C8—H8C 0.9600 C20—H20C 0.9600
C9—H9A 0.9600 O2—H2A 0.82 (6)
C9—H9B 0.9600
C6—C1—C2 108.0 (3) C3—C9—H9B 109.5
C6—C1—C7 110.2 (4) C3—C9—H9C 109.5
C6—C1—C13 111.3 (2) H9A—C9—H9B 109.5
C7—C1—C2 114.5 (3) H9A—C9—H9C 109.5
C13—C1—C2 106.8 (2) H9B—C9—H9C 109.5
C13—C1—C7 106.0 (2) C2—C10—H10 120.6
C1—C2—H2 104.1 C11—C10—C2 118.9 (4)
C1—C2—C3 116.5 (3) C11—C10—H10 120.6
C3—C2—H2 104.1 C10—C11—H11 121.5
C10—C2—C1 110.7 (3) C10—C11—C12 117.0 (3)
C10—C2—H2 104.1 C12—C11—H11 121.5
C10—C2—C3 115.5 (3) C11—C12—C17 116.8 (2)
C4—C3—C2 108.0 (3) C13—C12—C11 121.4 (3)
C4—C3—C9 107.5 (4) C13—C12—C17 121.8 (2)
C8—C3—C2 114.9 (3) C12—C13—C1 121.7 (2)
C8—C3—C4 111.3 (4) C12—C13—C14 116.9 (2)
C8—C3—C9 106.8 (4) C14—C13—C1 121.0 (2)
C9—C3—C2 108.0 (3) C13—C14—C15 119.2 (2)
C3—C4—H4A 109.0 O1—C14—C13 124.1 (3)
C3—C4—H4B 109.0 O1—C14—C15 116.8 (3)
H4A—C4—H4B 107.8 C16—C15—C14 122.8 (3)
C5—C4—C3 113.0 (3) C16—C15—O2 123.4 (3)
C5—C4—H4A 109.0 O2—C15—C14 113.8 (3)
C5—C4—H4B 109.0 C15—C16—C17 116.7 (2)
C4—C5—H5A 109.3 C15—C16—C18 124.7 (3)
C4—C5—H5B 109.3 C17—C16—C18 118.6 (3)
C4—C5—C6 111.6 (4) C16—C17—C12 120.4 (2)
H5A—C5—H5B 108.0 O3—C17—C12 118.8 (3)
C6—C5—H5A 109.3 O3—C17—C16 120.8 (3)
C6—C5—H5B 109.3 C16—C18—H18 107.1
C1—C6—C5 111.9 (3) C16—C18—C20 112.3 (3)
C1—C6—H6A 109.2 C19—C18—C16 111.0 (3)
C1—C6—H6B 109.2 C19—C18—H18 107.1
C5—C6—H6A 109.2 C19—C18—C20 111.9 (3)
C5—C6—H6B 109.2 C20—C18—H18 107.1
H6A—C6—H6B 107.9 C18—C19—H19A 109.5
C1—C7—H7A 109.5 C18—C19—H19B 109.5
C1—C7—H7B 109.5 C18—C19—H19C 109.5
C1—C7—H7C 109.5 H19A—C19—H19B 109.5
H7A—C7—H7B 109.5 H19A—C19—H19C 109.5
H7A—C7—H7C 109.5 H19B—C19—H19C 109.5
H7B—C7—H7C 109.5 C18—C20—H20A 109.5
C3—C8—H8A 109.5 C18—C20—H20B 109.5
C3—C8—H8B 109.5 C18—C20—H20C 109.5
C3—C8—H8C 109.5 H20A—C20—H20B 109.5
H8A—C8—H8B 109.5 H20A—C20—H20C 109.5
H8A—C8—H8C 109.5 H20B—C20—H20C 109.5
H8B—C8—H8C 109.5 C15—O2—H2A 101 (4)
C3—C9—H9A 109.5
C1—C2—C3—C4 52.3 (4) C11—C12—C13—C14 168.7 (3)
C1—C2—C3—C8 −72.7 (4) C17—C12—C13—C1 176.8 (2)
C1—C2—C3—C9 168.2 (4) C17—C12—C13—C14 −10.0 (4)
C1—C2—C10—C11 −50.7 (6) C11—C12—C17—C16 178.5 (3)
C1—C13—C14—C15 −169.1 (2) C11—C12—C17—O3 0.3 (4)
C1—C13—C14—O1 12.1 (4) C12—C13—C14—C15 17.7 (4)
C2—C1—C6—C5 54.3 (5) C12—C13—C14—O1 −161.1 (3)
C2—C1—C13—C12 −27.2 (3) C13—C1—C2—C3 −173.4 (3)
C2—C1—C13—C14 159.9 (2) C13—C1—C2—C10 51.8 (4)
C2—C3—C4—C5 −52.3 (4) C13—C1—C6—C5 171.2 (4)
C2—C10—C11—C12 17.7 (7) C13—C12—C17—C16 −2.5 (4)
C3—C2—C10—C11 174.0 (4) C13—C12—C17—O3 179.2 (3)
C3—C4—C5—C6 57.4 (6) C13—C14—C15—C16 −13.2 (4)
C4—C5—C6—C1 −58.2 (6) C13—C14—C15—O2 168.3 (3)
C6—C1—C2—C3 −53.7 (4) C14—C15—C16—C17 0.4 (4)
C6—C1—C2—C10 171.6 (3) C14—C15—C16—C18 178.0 (3)
C6—C1—C13—C12 −144.9 (3) C15—C16—C17—C12 7.6 (4)
C6—C1—C13—C14 42.2 (4) C15—C16—C17—O3 −174.3 (3)
C7—C1—C2—C3 69.5 (4) C15—C16—C18—C19 −70.0 (4)
C7—C1—C2—C10 −65.2 (4) C15—C16—C18—C20 56.2 (4)
C7—C1—C6—C5 −71.4 (5) C17—C12—C13—C1 176.7 (2)
C7—C1—C13—C12 95.2 (4) C17—C12—C13—C14 −10.1 (4)
C7—C1—C13—C14 −77.6 (4) C17—C16—C18—C19 107.6 (3)
C8—C3—C4—C5 74.7 (4) C17—C16—C18—C20 −126.3 (3)
C9—C3—C4—C5 −168.6 (4) C18—C16—C17—C12 −170.2 (2)
C10—C2—C3—C4 −175.2 (4) C18—C16—C17—O3 8.0 (4)
C10—C2—C3—C8 59.9 (5) O1—C14—C15—C16 165.6 (3)
C10—C2—C3—C9 −59.2 (5) O1—C14—C15—O2 −12.8 (4)
C10—C11—C12—C13 11.3 (5) O2—C15—C16—C17 178.7 (3)
C10—C11—C12—C17 −169.8 (4) O2—C15—C16—C18 −3.8 (5)
C11—C12—C13—C1 −4.4 (4)

Hydrogen-bond geometry (Å, º)

D—H···A D—H H···A D···A D—H···A
O2—H2A···O1 0.82 (6) 2.03 (5) 2.607 (3) 128 (5)
O2—H2A···O3i 0.82 (6) 2.53 (6) 3.160 (3) 135 (5)
C11—H11···O1ii 0.93 2.37 3.290 (3) 173 (5)

Symmetry codes: (i) x, y−1, z; (ii) x, y+1, z.

Funding Statement

This work was funded by Natural Science Foundation of Qinghai Province grant 2016-ZJ-908. National Natural Science Foundation of China grant grant 81573561.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989017017935/qm2118sup1.cif

e-74-00062-sup1.cif (275.2KB, cif)

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989017017935/qm2118Isup2.hkl

e-74-00062-Isup2.hkl (272.6KB, hkl)

Supporting information file. DOI: 10.1107/S2056989017017935/qm2118Isup3.cdx

Supporting information file. DOI: 10.1107/S2056989017017935/qm2118Isup4.cml

CCDC reference: 1551127

Additional supporting information: crystallographic information; 3D view; checkCIF report


Articles from Acta Crystallographica Section E: Crystallographic Communications are provided here courtesy of International Union of Crystallography

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