organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

6,8-Dihy­dr­oxy-8a-methyl-3,5-di­methyl­idenedeca­hydro­naphtho­[2,3-b]furan-2(3H)-one

aCollege of Life and Environment Science, Minzu University of China, Beijing 100081, People's Republic of China
*Correspondence e-mail: wangws@muc.edu.cn

(Received 1 August 2012; accepted 25 October 2012; online 31 October 2012)

The title compound, C15H20O4, is a eudesmanolide isolated from the Chinese medicinal plant Carpesium tris­te Maxim. The mol­ecule contains three rings, viz. two fused six-membered rings in chair conformations and a five-membered ring in a flattened envelope conformation. In the crystal, two hy­droxy groups are involved in the formation of intra- and inter­molecular O—H⋯O hydrogen bonds. The H atoms in these groups are split, with site-occupation factors of 0.5. The inter­molecular hydrogen bonds link mol­ecules into chains propagating in [010].

Related literature

For related compounds extracted from Carpesium tris­te Maxim, see: Masao & Fumiko (1975[Masao, M. & Fumiko, S. (1975). Phytochemistry, 14, 2247-2248.]).

[Scheme 1]

Experimental

Crystal data
  • C15H20O4

  • Mr = 264.31

  • Tetragonal, P 41 21 2

  • a = 6.4737 (4) Å

  • c = 62.438 (8) Å

  • V = 2616.7 (5) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 133 K

  • 0.54 × 0.48 × 0.32 mm

Data collection
  • Rigaku AFC10/Saturn-724+ CCD diffractometer

  • 19607 measured reflections

  • 1990 independent reflections

  • 1826 reflections with I > 2σ(I)

  • Rint = 0.058

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.124

  • S = 1.00

  • 1990 reflections

  • 185 parameters

  • 6 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2O⋯O2i 0.84 (1) 1.90 (1) 2.733 (3) 173 (5)
O2—H2O′⋯O3 0.84 (1) 1.94 (2) 2.690 (2) 148 (2)
O3—H3O′⋯O2 0.84 (1) 1.97 (4) 2.690 (2) 143 (5)
O3—H3O⋯O3ii 0.83 (1) 1.88 (2) 2.697 (3) 168 (6)
Symmetry codes: (i) y, x, -z; (ii) y+1, x-1, -z.

Data collection: CrystalClear (Rigaku/MSC, 2008[Rigaku/MSC (2008). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Carpesium triste Maxim grows in the northeast and southwest area of mainland China. It is used as traditional Chinese medicine having effects on detoxification and antibacterial activities. As a part of our research on biological resource by ethnic minorities in Guizhou province, the title compound was isolated form Carpesium triste Maxim. Its structure was identified by NMR spectra data and compared with the previous reports (Masao & Fumiko, 1975). Herewith we present its molecular structure. The molecule of the title compound contains a three-ring system A/B/C (Fig. 1). Ring A and B are both in chair conformations and there is a trans-junction between ring A (C1-C5/C10) and ring B (C5-C7/C8-C10). Furthermore, the methyl group at C14 sites is in the opposite orientation with the two hydroxyl groups at C1 and C3 sites. The furan ring C (C8-C12/O1) is in an envelope-like conformation. Two hydroxy groups contribute to the formation of intra- and inter-molecular O–H···O hydrogen bonds (Table 1). The latter ones link molecules into chain propagated in direction [0 1 0].

Related literature top

For related compounds extracted from Carpesium triste Maxim, see: Masao & Fumiko (1975).

Experimental top

The air-dried whole plant of Carpesium triste Maxim (0.337 kg) were pulverized and extracted three times with CH3OH (each for less than 1 minutes) at room temperature by flash-type extractor. The extract was concentrated to give a residue (33.5 g), which was further separated by CC (SiO2, 200-300 mesh, petroleum ether/acetone (25:1, 20:1, 15:1, 10:1, 8:1, 5:1, 3:1, 2:1, 1:1(v/v)) to yield 9 fractions: Fr. 1-9. Each fraction was examined by TLC and combined to afford many subfractions. Fr. 5 (270 mg) was subjected to Sephadex LH-20 (CHCl3/CH3OH 1:1) to provide the title compound (4 mg). 1H and 13C NMR spectral data of this compound was recorded on Bruker-AV-500 spectrometer, using CDCl3 as solvent and Me4Si as internal standard. The relative stereochemistry can be observed by X-ray diffraction experiment.

Refinement top

The hydrogen atoms which bonded with C were placed in calculated positions with C–H = 0.95-1.00Å. The hydroxyl H atoms were located in Fourier difference map. The H atoms in these droups are splitted with s.o.f. = 0.5. The positions of hydroxyl H atoms were refined freely. All H atoms were refined with Uiso(H) = 1.2Ueq(C, O).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2008); cell refinement: CrystalClear (Rigaku/MSC, 2008); data reduction: CrystalClear (Rigaku/MSC, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of the title molecule showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius. In the both hydroxy groups only one H atom is presented.
6,8-Dihydroxy-8a-methyl-3,5- dimethylidenedecahydronaphtho[2,3-b]furan-2(3H)-one top
Crystal data top
C15H20O4Dx = 1.342 Mg m3
Mr = 264.31Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P41212Cell parameters from 4658 reflections
Hall symbol: P 4abw 2nwθ = 3.2–27.9°
a = 6.4737 (4) ŵ = 0.10 mm1
c = 62.438 (8) ÅT = 133 K
V = 2616.7 (5) Å3Block, colourless
Z = 80.54 × 0.48 × 0.32 mm
F(000) = 1136
Data collection top
Rigaku AFC10/Saturn-724+ CCD
diffractometer
1826 reflections with I > 2σ(I)
Radiation source: Rotating AnodeRint = 0.058
Graphite monochromatorθmax = 27.9°, θmin = 2.6°
Detector resolution: 28.5714 pixels mm-1h = 88
ϕ– and ω–scansk = 88
19607 measured reflectionsl = 8282
1990 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0836P)2 + 0.316P]
where P = (Fo2 + 2Fc2)/3
1990 reflections(Δ/σ)max = 0.001
185 parametersΔρmax = 0.23 e Å3
6 restraintsΔρmin = 0.21 e Å3
Crystal data top
C15H20O4Z = 8
Mr = 264.31Mo Kα radiation
Tetragonal, P41212µ = 0.10 mm1
a = 6.4737 (4) ÅT = 133 K
c = 62.438 (8) Å0.54 × 0.48 × 0.32 mm
V = 2616.7 (5) Å3
Data collection top
Rigaku AFC10/Saturn-724+ CCD
diffractometer
1826 reflections with I > 2σ(I)
19607 measured reflectionsRint = 0.058
1990 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0476 restraints
wR(F2) = 0.124H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.23 e Å3
1990 reflectionsΔρmin = 0.21 e Å3
185 parameters
Special details top

Experimental. Since the skeleton methyl groups in eudesmanolide are biogenic 8a position, we draw the relative stereochemistry of the title eudesmanolide, by reference to the structures of related eudesmanolide in (Masao & Fumiko, 1975) although the absolute configuration could not be reliably determined from anomalous dispersion effects, if Mo radiation is used in experiment. Furthermore, the relative stereochemistry in the title compound was confirmed by NMR data. 13C NMR (125 MHz, CDCl3, δ,p.p.m.): 178.1 (C12), 149.2 (C4), 141.4 (C11), 120.5 (C13), 110.9 (C15), 77.6 (C8), 75.2 (C3), 74.7 (C1), 63.8 (C10), 40.3 (C7), 33.9 (C5), 33.6 (C9), 33.5 (C2), 26.8 (C6), 17.7 (C14).

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 > σ(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.6749 (2)0.7974 (2)0.09621 (2)0.0238 (3)
O20.9609 (2)0.7729 (3)0.01700 (2)0.0259 (4)
H2O0.903 (5)0.820 (6)0.0061 (5)0.031*0.50
H2O'1.080 (3)0.727 (4)0.0149 (8)0.031*0.50
O31.2633 (3)0.4894 (3)0.01385 (3)0.0277 (4)
H3O1.329 (7)0.432 (8)0.0040 (7)0.033*0.50
H3O'1.216 (8)0.609 (4)0.0132 (9)0.033*0.50
O40.6433 (3)0.7218 (3)0.13102 (3)0.0289 (4)
C10.8323 (3)0.6114 (3)0.02599 (3)0.0222 (4)
H10.68560.63820.02180.027*
C20.8995 (3)0.4040 (4)0.01641 (3)0.0252 (5)
H2A0.80230.29470.02100.030*
H2B0.89470.41240.00060.030*
C31.1183 (3)0.3474 (3)0.02353 (3)0.0230 (4)
H31.15040.20410.01860.028*
C41.1394 (3)0.3561 (3)0.04749 (3)0.0188 (4)
C51.0717 (3)0.5576 (3)0.05753 (3)0.0176 (4)
H51.16360.66810.05170.021*
C61.0932 (3)0.5634 (3)0.08181 (3)0.0197 (4)
H6A1.23690.52730.08570.024*
H6B1.00100.45780.08810.024*
C71.0399 (3)0.7753 (3)0.09141 (3)0.0199 (4)
H71.15900.87240.08980.024*
C80.8417 (3)0.8722 (3)0.08222 (3)0.0206 (4)
H80.85181.02540.08400.025*
C90.7925 (3)0.8280 (3)0.05891 (3)0.0208 (4)
H9A0.86630.93070.05000.025*
H9B0.64270.85020.05670.025*
C100.8472 (3)0.6116 (3)0.05061 (3)0.0196 (4)
C110.9826 (3)0.7535 (3)0.11464 (3)0.0221 (4)
C120.7532 (3)0.7548 (3)0.11580 (3)0.0217 (4)
C131.1009 (4)0.7239 (4)0.13160 (3)0.0287 (5)
H13A1.03990.70220.14530.034*
H13B1.24700.72430.13010.034*
C140.6907 (3)0.4523 (3)0.05931 (4)0.0235 (5)
H14A0.67280.47280.07470.028*
H14B0.74240.31240.05660.028*
H14C0.55770.47070.05210.028*
C151.2136 (3)0.1949 (3)0.05820 (4)0.0253 (5)
H15A1.25360.07350.05070.030*
H15B1.22670.20100.07330.030*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0227 (8)0.0298 (8)0.0189 (7)0.0009 (6)0.0021 (6)0.0013 (6)
O20.0313 (9)0.0272 (8)0.0192 (8)0.0013 (7)0.0007 (6)0.0057 (6)
O30.0311 (9)0.0287 (8)0.0232 (8)0.0024 (7)0.0085 (7)0.0027 (7)
O40.0321 (9)0.0319 (8)0.0228 (8)0.0021 (7)0.0073 (7)0.0024 (7)
C10.0221 (10)0.0250 (10)0.0196 (10)0.0023 (8)0.0023 (8)0.0024 (8)
C20.0281 (11)0.0314 (12)0.0161 (10)0.0054 (9)0.0024 (8)0.0028 (9)
C30.0272 (11)0.0210 (10)0.0208 (10)0.0026 (8)0.0038 (9)0.0021 (8)
C40.0183 (9)0.0207 (9)0.0173 (10)0.0031 (7)0.0014 (8)0.0015 (8)
C50.0182 (9)0.0187 (10)0.0158 (9)0.0015 (7)0.0012 (7)0.0003 (8)
C60.0215 (10)0.0211 (10)0.0164 (9)0.0004 (8)0.0008 (8)0.0014 (8)
C70.0213 (10)0.0212 (10)0.0171 (9)0.0017 (8)0.0012 (8)0.0010 (8)
C80.0241 (10)0.0198 (9)0.0178 (10)0.0008 (8)0.0015 (8)0.0009 (8)
C90.0222 (10)0.0212 (10)0.0190 (10)0.0024 (8)0.0002 (8)0.0025 (8)
C100.0183 (9)0.0234 (10)0.0169 (10)0.0012 (8)0.0011 (8)0.0017 (8)
C110.0265 (10)0.0202 (10)0.0197 (10)0.0004 (8)0.0014 (8)0.0010 (8)
C120.0282 (11)0.0201 (10)0.0169 (9)0.0007 (8)0.0015 (8)0.0007 (8)
C130.0318 (12)0.0360 (12)0.0182 (10)0.0009 (10)0.0014 (9)0.0003 (9)
C140.0203 (10)0.0257 (11)0.0245 (10)0.0056 (8)0.0015 (8)0.0005 (9)
C150.0256 (10)0.0246 (11)0.0255 (11)0.0009 (8)0.0008 (9)0.0012 (8)
Geometric parameters (Å, º) top
O1—C121.353 (3)C6—C71.536 (3)
O1—C81.471 (2)C6—H6A0.9900
O2—C11.449 (3)C6—H6B0.9900
O2—H2O0.840 (10)C7—C111.504 (3)
O2—H2O'0.839 (10)C7—C81.539 (3)
O3—C31.447 (3)C7—H71.0000
O3—H3O0.834 (10)C8—C91.517 (3)
O3—H3O'0.836 (10)C8—H81.0000
O4—C121.206 (3)C9—C101.535 (3)
C1—C21.533 (3)C9—H9A0.9900
C1—C101.540 (3)C9—H9B0.9900
C1—H11.0000C10—C141.544 (3)
C2—C31.529 (3)C11—C131.321 (3)
C2—H2A0.9900C11—C121.486 (3)
C2—H2B0.9900C13—H13A0.9500
C3—C41.503 (3)C13—H13B0.9500
C3—H31.0000C14—H14A0.9800
C4—C151.330 (3)C14—H14B0.9800
C4—C51.512 (3)C14—H14C0.9800
C5—C61.523 (3)C15—H15A0.9500
C5—C101.556 (3)C15—H15B0.9500
C5—H51.0000
C12—O1—C8109.21 (16)C11—C7—C8101.06 (17)
C1—O2—H2O108.7 (12)C6—C7—C8113.93 (16)
C1—O2—H2O'109.6 (12)C11—C7—H7110.4
H2O—O2—H2O'115 (5)C6—C7—H7110.4
C3—O3—H3O111 (4)C8—C7—H7110.4
C3—O3—H3O'112 (4)O1—C8—C9110.70 (17)
H3O—O3—H3O'124 (6)O1—C8—C7104.87 (15)
O2—C1—C2108.53 (17)C9—C8—C7117.13 (17)
O2—C1—C10110.48 (16)O1—C8—H8107.9
C2—C1—C10111.86 (17)C9—C8—H8107.9
O2—C1—H1108.6C7—C8—H8107.9
C2—C1—H1108.6C8—C9—C10116.56 (16)
C10—C1—H1108.6C8—C9—H9A108.2
C3—C2—C1111.05 (17)C10—C9—H9A108.2
C3—C2—H2A109.4C8—C9—H9B108.2
C1—C2—H2A109.4C10—C9—H9B108.2
C3—C2—H2B109.4H9A—C9—H9B107.3
C1—C2—H2B109.4C9—C10—C1108.84 (16)
H2A—C2—H2B108.0C9—C10—C14109.84 (17)
O3—C3—C4109.47 (17)C1—C10—C14108.02 (16)
O3—C3—C2109.10 (17)C9—C10—C5109.08 (16)
C4—C3—C2111.38 (17)C1—C10—C5109.60 (16)
O3—C3—H3108.9C14—C10—C5111.41 (17)
C4—C3—H3108.9C13—C11—C12122.7 (2)
C2—C3—H3108.9C13—C11—C7130.1 (2)
C15—C4—C3120.26 (19)C12—C11—C7107.06 (18)
C15—C4—C5124.99 (19)O4—C12—O1121.8 (2)
C3—C4—C5114.75 (17)O4—C12—C11128.8 (2)
C4—C5—C6114.06 (17)O1—C12—C11109.35 (17)
C4—C5—C10110.44 (16)C11—C13—H13A120.0
C6—C5—C10110.86 (16)C11—C13—H13B120.0
C4—C5—H5107.0H13A—C13—H13B120.0
C6—C5—H5107.0C10—C14—H14A109.5
C10—C5—H5107.0C10—C14—H14B109.5
C5—C6—C7112.94 (16)H14A—C14—H14B109.5
C5—C6—H6A109.0C10—C14—H14C109.5
C7—C6—H6A109.0H14A—C14—H14C109.5
C5—C6—H6B109.0H14B—C14—H14C109.5
C7—C6—H6B109.0C4—C15—H15A120.0
H6A—C6—H6B107.8C4—C15—H15B120.0
C11—C7—C6110.34 (17)H15A—C15—H15B120.0
O2—C1—C2—C365.9 (2)C8—C9—C10—C1474.5 (2)
C10—C1—C2—C356.2 (2)C8—C9—C10—C547.9 (2)
C1—C2—C3—O368.2 (2)O2—C1—C10—C955.0 (2)
C1—C2—C3—C452.7 (2)C2—C1—C10—C9176.05 (17)
O3—C3—C4—C15112.1 (2)O2—C1—C10—C14174.25 (17)
C2—C3—C4—C15127.1 (2)C2—C1—C10—C1464.7 (2)
O3—C3—C4—C567.6 (2)O2—C1—C10—C564.2 (2)
C2—C3—C4—C553.2 (2)C2—C1—C10—C556.8 (2)
C15—C4—C5—C60.6 (3)C4—C5—C10—C9173.51 (16)
C3—C4—C5—C6179.74 (17)C6—C5—C10—C959.1 (2)
C15—C4—C5—C10126.2 (2)C4—C5—C10—C154.4 (2)
C3—C4—C5—C1054.1 (2)C6—C5—C10—C1178.14 (16)
C4—C5—C6—C7175.41 (16)C4—C5—C10—C1465.1 (2)
C10—C5—C6—C759.2 (2)C6—C5—C10—C1462.4 (2)
C5—C6—C7—C11157.85 (17)C6—C7—C11—C1376.2 (3)
C5—C6—C7—C845.0 (2)C8—C7—C11—C13162.9 (2)
C12—O1—C8—C9153.66 (17)C6—C7—C11—C1299.4 (2)
C12—O1—C8—C726.4 (2)C8—C7—C11—C1221.5 (2)
C11—C7—C8—O128.42 (19)C8—O1—C12—O4168.33 (19)
C6—C7—C8—O189.89 (19)C8—O1—C12—C1112.6 (2)
C11—C7—C8—C9151.58 (17)C13—C11—C12—O43.7 (4)
C6—C7—C8—C933.3 (2)C7—C11—C12—O4172.3 (2)
O1—C8—C9—C1083.9 (2)C13—C11—C12—O1177.4 (2)
C7—C8—C9—C1036.2 (3)C7—C11—C12—O16.6 (2)
C8—C9—C10—C1167.46 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O2i0.84 (1)1.90 (1)2.733 (3)173 (5)
O2—H2O···O30.84 (1)1.94 (2)2.690 (2)148 (2)
O3—H3O···O20.84 (1)1.97 (4)2.690 (2)143 (5)
O3—H3O···O3ii0.83 (1)1.88 (2)2.697 (3)168 (6)
Symmetry codes: (i) y, x, z; (ii) y+1, x1, z.

Experimental details

Crystal data
Chemical formulaC15H20O4
Mr264.31
Crystal system, space groupTetragonal, P41212
Temperature (K)133
a, c (Å)6.4737 (4), 62.438 (8)
V3)2616.7 (5)
Z8
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.54 × 0.48 × 0.32
Data collection
DiffractometerRigaku AFC10/Saturn-724+ CCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
19607, 1990, 1826
Rint0.058
(sin θ/λ)max1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.124, 1.00
No. of reflections1990
No. of parameters185
No. of restraints6
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.23, 0.21

Computer programs: CrystalClear (Rigaku/MSC, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O2i0.840 (10)1.898 (12)2.733 (3)173 (5)
O2—H2O'···O30.839 (10)1.942 (17)2.690 (2)147.9 (17)
O3—H3O'···O20.836 (10)1.97 (4)2.690 (2)143 (5)
O3—H3O···O3ii0.834 (10)1.876 (16)2.697 (3)168 (6)
Symmetry codes: (i) y, x, z; (ii) y+1, x1, z.
 

Acknowledgements

The project was supported by the 985 Project (grant Nos. MUC98504-14, MUC98507-08), Minzu University of China, together with the `Programme of Introducing Talents of Discipline to Universities' (grant No. B08044), and the `Project for Scientific and Technical Achievements in Industrialization', Beijing Education Commission.

References

First citationMasao, M. & Fumiko, S. (1975). Phytochemistry, 14, 2247–2248.
First citationRigaku/MSC (2008). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA.
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds