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

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ISSN: 2056-9890

Cinnamyl 8-meth­­oxy-2-oxo-2H-chromene-3-carboxyl­ate

aCollege of Sciences, Henan Agricultural University, Zhengzhou 450002, People's Republic of China, and bCollege of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, People's Republic of China
*Correspondence e-mail: xucuilian666@126.com

(Received 16 September 2009; accepted 12 October 2009; online 23 October 2009)

In the crystal structure of the title compound, C20H16O5, the mol­ecule assumes an E configuration with the benzene ring and chromenecarboxyl group located on opposite ends of the C=C double bond. The chromene ring system and benzene ring are oriented at a dihedral angle of 74.66 (12)°. Weak inter­molecular C—H⋯O hydrogen bonding is present in the crystal structure.

Related literature

For applications of coumarins and related compounds, see: Hoult & Paya (1996[Hoult, J. R. R. & Paya, M. (1996). Gen. Pharmacol. 27, 713-722.]); Yu et al. (2003[Yu, D., Suzuki, M., Xie, L., Susan, L., Morris-Natschke, S. L. & Lee, K.-H. (2003). Med. Res. Rev. 23, 322-345.], 2007[Yu, D., Morris-Natschke, S. L. & Lee, K.-H. (2007). Med. Res. Rev. 27, 108-132.]); Finn et al. (2004[Finn, G. J., Creaven, B. S. & Egan, D. A. (2004). Cancer Lett. 214, 43-54.]).

[Scheme 1]

Experimental

Crystal data
  • C20H16O5

  • Mr = 336.33

  • Monoclinic, P 21 /c

  • a = 19.226 (4) Å

  • b = 9.5483 (19) Å

  • c = 9.0046 (18) Å

  • β = 90.97 (3)°

  • V = 1652.8 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.20 × 0.17 × 0.17 mm

Data collection
  • Bruker SMART CCD area detector diffractometer

  • Absorption correction: none

  • 4903 measured reflections

  • 2834 independent reflections

  • 2157 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.065

  • wR(F2) = 0.155

  • S = 1.15

  • 2834 reflections

  • 228 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C4—H4A⋯O3i 0.93 2.51 3.429 (3) 170
C17—H17A⋯O4ii 0.93 2.44 3.294 (4) 153
Symmetry codes: (i) x, y+1, z; (ii) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Coumarins and related compounds, kinds of plant-derived compounds, have diverse biological activities, including anti-HIV, anti-bacterial, anti-inflammatory, anti-proliferative and antioxidant properties (Hoult & Paya, 1996; Yu et al., 2003; Finn et al., 2004; Yu et al., 2007). It thus appeared of interest to synthesize the compounds with coumarin-skeleton. As part of work, we have synthesized the title compound (I) and report its crystal structure here.

The title molecule crystallizes in the E conformation, with an C12-C13-C14-C15 torsion angle of -179.5 (3)°. The 8-methoxy-2H-chromen-2-one ring and the C15-benzene ring make a dihedral of 74.66 (12)°.

In the crystal structure, an intramolecular C—H···O hydrogen bond is observed and helps to stablize the conformation of the molecule.

Related literature top

For applications of coumarins and related compounds, see: Hoult & Paya (1996); Yu et al. (2003, 2007); Finn et al. (2004).

Experimental top

A solution of cinnamic alcohol (7.2 mmol) dissolved in dried methyl dichloride (DCM) (25 ml) was added dropwise to a solution of 2-oxo-2H-chromene-3-acyl chloride (7.2 mmol) dissolved in DCM (25 ml) and triethylamine (1 ml) at room temperature. The reaction mixture was stirred for 24 h, monitored by TLC. The reaction mixture was neutralized with 5% HCl and washed by saturated NaHCO3 solution and brine, respectively. The organic phase is dried over Na2SO4 and evaporated under the reduced pressure. The resulting residue was purified by column chromatography (EtOAc:petroleum ether) to give the purified compound.

Refinement top

All H atoms were positioned geometrically and refined as riding with C—H = 0.93 (aromatic), 0.97 (methylene) and 0.96 Å (methyl), Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for the others.

Structure description top

Coumarins and related compounds, kinds of plant-derived compounds, have diverse biological activities, including anti-HIV, anti-bacterial, anti-inflammatory, anti-proliferative and antioxidant properties (Hoult & Paya, 1996; Yu et al., 2003; Finn et al., 2004; Yu et al., 2007). It thus appeared of interest to synthesize the compounds with coumarin-skeleton. As part of work, we have synthesized the title compound (I) and report its crystal structure here.

The title molecule crystallizes in the E conformation, with an C12-C13-C14-C15 torsion angle of -179.5 (3)°. The 8-methoxy-2H-chromen-2-one ring and the C15-benzene ring make a dihedral of 74.66 (12)°.

In the crystal structure, an intramolecular C—H···O hydrogen bond is observed and helps to stablize the conformation of the molecule.

For applications of coumarins and related compounds, see: Hoult & Paya (1996); Yu et al. (2003, 2007); Finn et al. (2004).

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level for non-H atoms.
cinnamyl 8-methoxy-2-oxo-2H-chromene-3-carboxylate top
Crystal data top
C20H16O5F(000) = 704
Mr = 336.33Dx = 1.352 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2834 reflections
a = 19.226 (4) Åθ = 3.1–24.2°
b = 9.5483 (19) ŵ = 0.10 mm1
c = 9.0046 (18) ÅT = 296 K
β = 90.97 (3)°Block, colorless
V = 1652.8 (6) Å30.20 × 0.17 × 0.17 mm
Z = 4
Data collection top
Bruker SMART CCD area detector
diffractometer
2157 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.053
Graphite monochromatorθmax = 25.0°, θmin = 1.1°
ω scansh = 2222
4903 measured reflectionsk = 1111
2834 independent reflectionsl = 010
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.065H-atom parameters constrained
wR(F2) = 0.155 w = 1/[σ2(Fo2) + (0.0659P)2 + 0.2012P]
where P = (Fo2 + 2Fc2)/3
S = 1.15(Δ/σ)max = 0.001
2834 reflectionsΔρmax = 0.24 e Å3
228 parametersΔρmin = 0.20 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.024 (3)
Crystal data top
C20H16O5V = 1652.8 (6) Å3
Mr = 336.33Z = 4
Monoclinic, P21/cMo Kα radiation
a = 19.226 (4) ŵ = 0.10 mm1
b = 9.5483 (19) ÅT = 296 K
c = 9.0046 (18) Å0.20 × 0.17 × 0.17 mm
β = 90.97 (3)°
Data collection top
Bruker SMART CCD area detector
diffractometer
2157 reflections with I > 2σ(I)
4903 measured reflectionsRint = 0.053
2834 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0650 restraints
wR(F2) = 0.155H-atom parameters constrained
S = 1.15Δρmax = 0.24 e Å3
2834 reflectionsΔρmin = 0.20 e Å3
228 parameters
Special details top

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.

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*/Ueq
O10.04001 (9)0.88854 (18)0.70962 (19)0.0610 (5)
O20.11713 (7)0.72996 (15)0.54027 (17)0.0463 (4)
O30.15130 (10)0.51497 (17)0.4995 (2)0.0705 (6)
O40.25790 (11)0.4732 (2)0.3000 (3)0.0885 (7)
O50.28952 (8)0.66346 (19)0.17300 (19)0.0617 (5)
C10.12199 (11)0.8722 (2)0.5210 (2)0.0414 (6)
C20.08113 (11)0.9568 (3)0.6115 (3)0.0497 (6)
C30.08597 (14)1.0996 (3)0.5946 (3)0.0652 (8)
H3A0.05931.15780.65360.078*
C40.13001 (15)1.1585 (3)0.4910 (3)0.0710 (8)
H4A0.13231.25540.48160.085*
C50.17013 (13)1.0757 (3)0.4023 (3)0.0605 (7)
H5A0.19921.11600.33280.073*
C60.16698 (11)0.9293 (2)0.4174 (3)0.0445 (6)
C70.20856 (11)0.8339 (2)0.3351 (2)0.0450 (6)
H7A0.23830.86930.26380.054*
C80.20641 (10)0.6940 (2)0.3568 (2)0.0429 (6)
C90.15868 (11)0.6355 (2)0.4665 (3)0.0460 (6)
C100.25260 (12)0.5959 (3)0.2770 (3)0.0525 (6)
C110.00432 (15)0.9739 (3)0.7994 (3)0.0743 (8)
H11A0.03140.91500.86260.112*
H11B0.03491.02780.73620.112*
H11C0.02371.03600.85920.112*
C120.33877 (13)0.5785 (3)0.0894 (3)0.0697 (8)
H12A0.34700.62240.00590.084*
H12B0.31890.48670.07090.084*
C130.40569 (13)0.5629 (3)0.1714 (3)0.0646 (7)
H13A0.40530.51420.26080.078*
C140.46490 (14)0.6123 (3)0.1279 (3)0.0639 (7)
H14A0.46400.66130.03860.077*
C150.53343 (12)0.6000 (3)0.2031 (3)0.0560 (7)
C160.58725 (14)0.6863 (3)0.1617 (4)0.0741 (9)
H16A0.58040.74810.08300.089*
C170.65113 (15)0.6830 (3)0.2345 (5)0.0831 (10)
H17A0.68610.74450.20670.100*
C180.66314 (14)0.5891 (3)0.3481 (4)0.0741 (9)
H18A0.70590.58740.39800.089*
C190.61138 (15)0.4981 (4)0.3866 (3)0.0763 (9)
H19A0.61950.43200.46080.092*
C200.54716 (14)0.5041 (3)0.3158 (3)0.0694 (8)
H20A0.51230.44260.34430.083*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0600 (10)0.0639 (11)0.0597 (11)0.0079 (9)0.0171 (8)0.0059 (9)
O20.0487 (9)0.0410 (9)0.0494 (10)0.0015 (7)0.0053 (7)0.0008 (7)
O30.0869 (14)0.0375 (10)0.0877 (14)0.0016 (9)0.0227 (10)0.0041 (9)
O40.1028 (16)0.0562 (13)0.1075 (17)0.0296 (11)0.0322 (13)0.0052 (11)
O50.0522 (10)0.0719 (12)0.0615 (12)0.0113 (9)0.0125 (8)0.0069 (9)
C10.0391 (12)0.0364 (12)0.0486 (14)0.0004 (10)0.0026 (10)0.0021 (10)
C20.0444 (13)0.0505 (15)0.0541 (15)0.0053 (11)0.0019 (11)0.0051 (12)
C30.0668 (17)0.0523 (16)0.0767 (19)0.0122 (13)0.0061 (14)0.0112 (14)
C40.0784 (19)0.0382 (14)0.096 (2)0.0072 (13)0.0005 (17)0.0028 (15)
C50.0590 (16)0.0446 (14)0.0783 (19)0.0029 (12)0.0079 (13)0.0063 (13)
C60.0394 (12)0.0392 (12)0.0550 (15)0.0021 (10)0.0010 (10)0.0012 (11)
C70.0370 (12)0.0503 (14)0.0477 (14)0.0026 (10)0.0007 (9)0.0011 (11)
C80.0364 (12)0.0444 (13)0.0476 (14)0.0026 (10)0.0039 (10)0.0026 (10)
C90.0472 (13)0.0401 (14)0.0506 (15)0.0028 (10)0.0024 (10)0.0044 (11)
C100.0470 (14)0.0573 (16)0.0531 (16)0.0102 (12)0.0031 (11)0.0058 (13)
C110.0676 (18)0.090 (2)0.0663 (19)0.0167 (16)0.0152 (14)0.0173 (16)
C120.0520 (16)0.093 (2)0.0642 (18)0.0203 (14)0.0082 (13)0.0162 (16)
C130.0517 (15)0.0826 (19)0.0598 (17)0.0113 (14)0.0072 (12)0.0058 (15)
C140.0605 (16)0.0681 (17)0.0635 (17)0.0112 (14)0.0127 (13)0.0002 (14)
C150.0484 (14)0.0513 (14)0.0690 (18)0.0042 (12)0.0139 (12)0.0074 (13)
C160.0617 (18)0.0521 (16)0.109 (2)0.0106 (14)0.0295 (16)0.0079 (16)
C170.0542 (18)0.0535 (17)0.143 (3)0.0068 (14)0.0329 (18)0.012 (2)
C180.0490 (16)0.078 (2)0.096 (2)0.0006 (15)0.0078 (15)0.0310 (19)
C190.0669 (18)0.091 (2)0.071 (2)0.0004 (17)0.0080 (15)0.0048 (16)
C200.0549 (16)0.0741 (19)0.080 (2)0.0136 (14)0.0122 (14)0.0070 (16)
Geometric parameters (Å, º) top
O1—C21.362 (3)C11—H11A0.9600
O1—C111.438 (3)C11—H11B0.9600
O2—C11.373 (3)C11—H11C0.9600
O2—C91.382 (3)C12—C131.480 (4)
O3—C91.198 (3)C12—H12A0.9700
O4—C101.194 (3)C12—H12B0.9700
O5—C101.349 (3)C13—C141.299 (4)
O5—C121.465 (3)C13—H13A0.9300
C1—C61.394 (3)C14—C151.476 (4)
C1—C21.398 (3)C14—H14A0.9300
C2—C31.375 (4)C15—C161.379 (3)
C3—C41.389 (4)C15—C201.389 (4)
C3—H3A0.9300C16—C171.383 (4)
C4—C51.370 (4)C16—H16A0.9300
C4—H4A0.9300C17—C181.377 (4)
C5—C61.405 (3)C17—H17A0.9300
C5—H5A0.9300C18—C191.370 (4)
C6—C71.428 (3)C18—H18A0.9300
C7—C81.351 (3)C19—C201.381 (4)
C7—H7A0.9300C19—H19A0.9300
C8—C91.469 (3)C20—H20A0.9300
C8—C101.485 (3)
C2—O1—C11116.7 (2)H11A—C11—H11B109.5
C1—O2—C9122.93 (18)O1—C11—H11C109.5
C10—O5—C12116.4 (2)H11A—C11—H11C109.5
O2—C1—C6121.0 (2)H11B—C11—H11C109.5
O2—C1—C2117.3 (2)O5—C12—C13111.3 (2)
C6—C1—C2121.7 (2)O5—C12—H12A109.4
O1—C2—C3126.0 (2)C13—C12—H12A109.4
O1—C2—C1116.1 (2)O5—C12—H12B109.4
C3—C2—C1117.9 (2)C13—C12—H12B109.4
C2—C3—C4121.3 (3)H12A—C12—H12B108.0
C2—C3—H3A119.4C14—C13—C12124.9 (3)
C4—C3—H3A119.4C14—C13—H13A117.6
C5—C4—C3120.9 (2)C12—C13—H13A117.6
C5—C4—H4A119.6C13—C14—C15127.8 (3)
C3—C4—H4A119.6C13—C14—H14A116.1
C4—C5—C6119.5 (2)C15—C14—H14A116.1
C4—C5—H5A120.3C16—C15—C20117.2 (3)
C6—C5—H5A120.3C16—C15—C14119.8 (3)
C1—C6—C5118.8 (2)C20—C15—C14123.0 (2)
C1—C6—C7117.2 (2)C15—C16—C17121.5 (3)
C5—C6—C7124.0 (2)C15—C16—H16A119.2
C8—C7—C6122.5 (2)C17—C16—H16A119.2
C8—C7—H7A118.7C18—C17—C16120.2 (3)
C6—C7—H7A118.7C18—C17—H17A119.9
C7—C8—C9119.6 (2)C16—C17—H17A119.9
C7—C8—C10122.2 (2)C19—C18—C17119.2 (3)
C9—C8—C10118.1 (2)C19—C18—H18A120.4
O3—C9—O2115.8 (2)C17—C18—H18A120.4
O3—C9—C8127.6 (2)C18—C19—C20120.3 (3)
O2—C9—C8116.62 (19)C18—C19—H19A119.9
O4—C10—O5123.1 (2)C20—C19—H19A119.9
O4—C10—C8125.8 (3)C19—C20—C15121.5 (3)
O5—C10—C8111.2 (2)C19—C20—H20A119.3
O1—C11—H11A109.5C15—C20—H20A119.3
O1—C11—H11B109.5
C9—O2—C1—C64.0 (3)C7—C8—C9—O3179.1 (2)
C9—O2—C1—C2174.71 (19)C10—C8—C9—O31.1 (3)
C11—O1—C2—C32.6 (4)C7—C8—C9—O21.1 (3)
C11—O1—C2—C1177.7 (2)C10—C8—C9—O2179.11 (18)
O2—C1—C2—O10.4 (3)C12—O5—C10—O41.3 (3)
C6—C1—C2—O1179.15 (19)C12—O5—C10—C8178.20 (18)
O2—C1—C2—C3179.3 (2)C7—C8—C10—O4172.9 (3)
C6—C1—C2—C30.6 (3)C9—C8—C10—O45.0 (4)
O1—C2—C3—C4179.8 (2)C7—C8—C10—O56.5 (3)
C1—C2—C3—C40.0 (4)C9—C8—C10—O5175.55 (18)
C2—C3—C4—C50.1 (4)C10—O5—C12—C1383.6 (3)
C3—C4—C5—C60.5 (4)O5—C12—C13—C14115.1 (3)
O2—C1—C6—C5179.8 (2)C12—C13—C14—C15179.5 (3)
C2—C1—C6—C51.2 (3)C13—C14—C15—C16164.1 (3)
O2—C1—C6—C71.3 (3)C13—C14—C15—C2015.9 (4)
C2—C1—C6—C7177.37 (19)C20—C15—C16—C173.4 (4)
C4—C5—C6—C11.1 (4)C14—C15—C16—C17176.6 (3)
C4—C5—C6—C7177.4 (2)C15—C16—C17—C182.2 (4)
C1—C6—C7—C81.3 (3)C16—C17—C18—C190.7 (4)
C5—C6—C7—C8177.1 (2)C17—C18—C19—C202.3 (4)
C6—C7—C8—C91.4 (3)C18—C19—C20—C150.9 (4)
C6—C7—C8—C10176.50 (19)C16—C15—C20—C191.9 (4)
C1—O2—C9—O3176.3 (2)C14—C15—C20—C19178.2 (3)
C1—O2—C9—C83.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4A···O3i0.932.513.429 (3)170
C17—H17A···O4ii0.932.443.294 (4)153
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC20H16O5
Mr336.33
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)19.226 (4), 9.5483 (19), 9.0046 (18)
β (°) 90.97 (3)
V3)1652.8 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.20 × 0.17 × 0.17
Data collection
DiffractometerBruker SMART CCD area detector
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
4903, 2834, 2157
Rint0.053
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.065, 0.155, 1.15
No. of reflections2834
No. of parameters228
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.20

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4A···O3i0.932.513.429 (3)170
C17—H17A···O4ii0.932.443.294 (4)153
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1/2, z+1/2.
 

Acknowledgements

This work was supported by the Natural Science Foundation of Henan Province (No. 2009 A150012).

References

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