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

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5,5,7,12,12,14-Hexa­methyl-1,8-bis­­(4-nitro­benz­yl)-1,4,8,11-tetra­aza­cyclo­tetra­deca­ne

aPG and Research Department of Physics, Queen Mary's College, Chennai-4, Tamilnadu, India, and bDepartment of Inorganic Chemistry, University of Madras, Maraimalai Campus, Chennai-25, Tamilnadu, India
*Correspondence e-mail: guqmc@yahoo.com

(Received 13 September 2013; accepted 13 November 2013; online 14 December 2013)

The asymmetric unit of the title compound, C30H46N6O4, contains one half-mol­ecule. The C(benzene)—C(CH2)—N—C(—Me) torsion angle is −79.89 (13)° suggesting a synclinal orientation of the nitro­benzene ring with respect to the macrocycle. The conformation of the macrocycle is stabilized by intra­molecular N—H⋯N hydrogen bonds.

Related literature

For the biological activity of cyclam derivatives, see: Cronin et al. (1999[Cronin, L., Mount, A. R., Parsons, S. & Robertson, N. (1999). J. Chem. Soc. Dalton Trans. pp. 1925-1927.]); Fzerov et al. (2005[Fzerov, S., Kotek, J., Csaov, I., Hermann, P., Koen Binnemans, K. & Luke, I. (2005). Dalton Trans. pp. 2908-2915.]). For related structures, see: Xie et al. (2008[Xie, B., Zou, L.-K., He, Y.-G., Feng, J.-S. & Zhang, X.-L. (2008). Acta Cryst. E64, m622.]); Feng et al. (2009[Feng, J.-S., Zou, L.-K., Xie, B. & Wu, Y. (2009). Acta Cryst. E65, m1022.]).

[Scheme 1]

Experimental

Crystal data
  • C30H46N6O4

  • Mr = 554.73

  • Triclinic, [P \overline 1]

  • a = 8.6407 (4) Å

  • b = 9.1433 (3) Å

  • c = 11.0008 (5) Å

  • α = 107.742 (2)°

  • β = 104.898 (2)°

  • γ = 102.372 (2)°

  • V = 758.45 (6) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 273 K

  • 0.35 × 0.30 × 0.25 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.972, Tmax = 0.980

  • 18201 measured reflections

  • 4819 independent reflections

  • 3340 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.185

  • S = 0.96

  • 4819 reflections

  • 185 parameters

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

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3A⋯N2i 0.883 (17) 2.284 (17) 2.9770 (15) 135.3 (15)
Symmetry code: (i) -x, -y+1, -z.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Cyclam based complexes have been used in a wide range of studies from bioinorganic systems to catalytic systems and as sensors (Cronin et al., 1999). Cyclam based anti-HIV agents are more active in vivo in the form of metal ion complexes. Macrocyclic ligands are also commonly used as carriers of metal radioisotopes in targeted radiopharmaceuticals. For utilization in nuclear medicine, macrocyclic ligands are generally preferred to open-chain ligands due to the higher thermodynamic and mainly kinetic stabilities of their complexes (Fzerov et al., 2005).

As part of our studies to examine the cyclam derivatives,we report the structure of the title compound (Fig. 1). The C–C bond lengths of the methyl groups attached to the macrocycle [C12—C13 = 1.535 (2) Å, C12—C14 = 1.532 (2) Å and C1—C8 = 1.533 (3) Å] are in good agreement with the literature values [C6—C7=1.53 (5) Å, C6—C8=1.541 (5) Å and C3—C5=1.535 (4) Å in Xie et al., 2008]. The bond angle C11—N3—C12 in the cyclam ring is 115.96 (1)° which agrees with the value 115.4 (3)° of the related reported structure (Feng et al., 2009). The sum of the angles around N1 atom [360 °], N2 atom [339.44°] and N3 atom [333.76 °] is an indication of sp2, sp3 and sp3hybridization, respectively. The conformation of the macrocycle is stabilized by intramolecular N—H···N hydrogen bonds (Table 1).

Related literature top

For the biological activity of cyclam derivatives, see: Cronin et al. (1999); Fzerov et al. (2005). For a related structure, see: Xie et al. (2008); Feng et al. (2009).

Experimental top

The ligand 1,8-bi(para-nitro benzyl)-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (L) (0.57 g, 2 mmol) was dissolved in 20 ml of methanol, and then sodium carbonate (0.636 g, 6 mmol) dissolved in 2 ml of water and potassium iodide (1 g, 6 mmol) were added to the above solution. Para-nitrobenzyl bromide (0.95 g, 4.4 mmol) in methanol was slowly added to the reaction mixture and refluxed for 12 h. The resulting yellow color product was washed with water, methanol and diethyl ether and it was recrystallized from a mixture of chloroform-methanol (75:25). Yield 0.83 g (75%).

Refinement top

H atoms were positioned geometrically and treated as riding on their parent atoms, with C—H distances of 0.93–0.98 Å and Uiso(H)= 1.5Ueq(C-methyl) or Uiso(H)= 1.2Ueq(N,C) for other H atoms. H3A was found in a difference Fourier map.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level and hydrogen bonds shown as broken lines. [Symmetry code: (1) -x, -y + 1, -z]
5,5,7,12,12,14-Hexamethyl-1,8-bis(4-nitrobenzyl)-1,4,8,11-tetraazacyclotetradecane top
Crystal data top
C30H46N6O4V = 758.45 (6) Å3
Mr = 554.73Z = 1
Triclinic, P1F(000) = 300
Hall symbol: -P 1Dx = 1.215 Mg m3
a = 8.6407 (4) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.1433 (3) Åθ = 1.0–31.1°
c = 11.0008 (5) ŵ = 0.08 mm1
α = 107.742 (2)°T = 273 K
β = 104.898 (2)°Block, colourless
γ = 102.372 (2)°0.35 × 0.30 × 0.25 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
4819 independent reflections
Radiation source: fine-focus sealed tube3340 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ω and ϕ scanθmax = 31.1°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 1212
Tmin = 0.972, Tmax = 0.980k = 1311
18201 measured reflectionsl = 1515
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.185H atoms treated by a mixture of independent and constrained refinement
S = 0.96 w = 1/[σ2(Fo2) + (0.1167P)2 + 0.0862P]
where P = (Fo2 + 2Fc2)/3
4819 reflections(Δ/σ)max < 0.001
185 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C30H46N6O4γ = 102.372 (2)°
Mr = 554.73V = 758.45 (6) Å3
Triclinic, P1Z = 1
a = 8.6407 (4) ÅMo Kα radiation
b = 9.1433 (3) ŵ = 0.08 mm1
c = 11.0008 (5) ÅT = 273 K
α = 107.742 (2)°0.35 × 0.30 × 0.25 mm
β = 104.898 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
4819 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
3340 reflections with I > 2σ(I)
Tmin = 0.972, Tmax = 0.980Rint = 0.028
18201 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0510 restraints
wR(F2) = 0.185H atoms treated by a mixture of independent and constrained refinement
S = 0.96Δρmax = 0.22 e Å3
4819 reflectionsΔρmin = 0.22 e Å3
185 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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*/Ueq
C10.17573 (15)0.33128 (15)0.19940 (12)0.0405 (3)
H10.19590.39750.29420.049*
C20.26370 (18)0.93648 (14)0.50435 (14)0.0469 (3)
C30.19243 (17)0.89974 (15)0.36661 (14)0.0466 (3)
H30.12030.95250.33460.056*
C40.23154 (16)0.78245 (15)0.27817 (13)0.0431 (3)
H40.18490.75540.18500.052*
C50.33941 (14)0.70422 (13)0.32604 (12)0.0384 (3)
C60.40708 (17)0.74400 (16)0.46470 (13)0.0469 (3)
H60.47910.69150.49740.056*
C70.37823 (15)0.57761 (15)0.22457 (13)0.0441 (3)
H7A0.42920.62590.17120.053*
H7B0.45840.53660.27240.053*
C80.2822 (2)0.2174 (2)0.20329 (19)0.0615 (4)
H8A0.39980.27990.24380.092*
H8B0.25960.14440.11230.092*
H8C0.25370.15650.25620.092*
C90.01195 (16)0.23196 (14)0.13605 (14)0.0427 (3)
H9A0.02950.15010.17460.051*
H9B0.03660.17550.03960.051*
C100.22706 (16)0.36646 (14)0.00178 (12)0.0395 (3)
H10A0.12260.27760.05450.047*
H10B0.31900.32080.00560.047*
C110.24794 (16)0.47711 (16)0.07869 (14)0.0439 (3)
H11A0.36460.54630.04220.053*
H11B0.22310.41180.17350.053*
C120.14282 (15)0.68065 (14)0.15082 (13)0.0403 (3)
C130.31661 (18)0.81153 (19)0.08704 (18)0.0604 (4)
H13A0.40250.76140.09440.091*
H13B0.33680.87050.00720.091*
H13C0.31930.88450.13390.091*
C140.1105 (2)0.5867 (2)0.30121 (15)0.0606 (4)
H14A0.00170.50510.34120.091*
H14B0.19620.53630.30880.091*
H14C0.11350.65990.34790.091*
C150.36900 (19)0.86074 (17)0.55532 (13)0.0512 (3)
H150.41390.88700.64850.061*
N10.2281 (2)1.06532 (16)0.59985 (15)0.0653 (4)
N20.22416 (11)0.44428 (11)0.13438 (9)0.0347 (2)
N30.13852 (12)0.57798 (12)0.07040 (10)0.0348 (2)
O10.1657 (2)1.15487 (16)0.55712 (16)0.0867 (4)
O20.2633 (3)1.0778 (2)0.71694 (15)0.1117 (6)
H3A0.0333 (19)0.5159 (18)0.0954 (14)0.044 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0390 (6)0.0426 (6)0.0402 (6)0.0128 (5)0.0113 (5)0.0180 (5)
C20.0518 (7)0.0350 (6)0.0468 (7)0.0052 (5)0.0239 (6)0.0065 (5)
C30.0470 (7)0.0391 (6)0.0524 (7)0.0137 (5)0.0168 (6)0.0159 (5)
C40.0444 (7)0.0404 (6)0.0378 (6)0.0096 (5)0.0113 (5)0.0112 (5)
C50.0322 (5)0.0337 (5)0.0386 (6)0.0031 (4)0.0095 (4)0.0070 (4)
C60.0462 (7)0.0452 (6)0.0417 (6)0.0120 (5)0.0087 (5)0.0134 (5)
C70.0316 (5)0.0425 (6)0.0463 (7)0.0077 (5)0.0113 (5)0.0059 (5)
C80.0553 (9)0.0637 (9)0.0778 (11)0.0282 (7)0.0172 (8)0.0418 (8)
C90.0419 (6)0.0371 (5)0.0501 (7)0.0102 (5)0.0157 (5)0.0198 (5)
C100.0407 (6)0.0396 (6)0.0391 (6)0.0187 (5)0.0156 (5)0.0107 (5)
C110.0428 (6)0.0531 (7)0.0473 (7)0.0237 (5)0.0248 (5)0.0209 (5)
C120.0388 (6)0.0420 (6)0.0438 (6)0.0101 (5)0.0189 (5)0.0194 (5)
C130.0415 (7)0.0556 (8)0.0866 (11)0.0069 (6)0.0256 (7)0.0333 (8)
C140.0729 (10)0.0772 (10)0.0474 (8)0.0301 (8)0.0322 (7)0.0305 (7)
C150.0579 (8)0.0488 (7)0.0362 (6)0.0087 (6)0.0126 (6)0.0107 (5)
N10.0779 (9)0.0465 (6)0.0655 (8)0.0149 (6)0.0370 (7)0.0067 (6)
N20.0322 (4)0.0321 (4)0.0349 (5)0.0084 (3)0.0110 (4)0.0082 (3)
N30.0325 (5)0.0385 (5)0.0371 (5)0.0123 (4)0.0163 (4)0.0152 (4)
O10.1035 (11)0.0574 (7)0.0994 (10)0.0386 (7)0.0451 (9)0.0127 (7)
O20.1857 (18)0.0998 (11)0.0652 (9)0.0661 (12)0.0679 (10)0.0175 (8)
Geometric parameters (Å, º) top
C1—N21.4742 (15)C9—H9B0.9700
C1—C91.5305 (17)C10—N21.4588 (15)
C1—C81.5328 (19)C10—C111.5145 (17)
C1—H10.9800C10—H10A0.9700
C2—C151.366 (2)C10—H10B0.9700
C2—C31.382 (2)C11—N31.4559 (16)
C2—N11.4675 (18)C11—H11A0.9700
C3—C41.3781 (18)C11—H11B0.9700
C3—H30.9300C12—N31.4743 (15)
C4—C51.3859 (18)C12—C9i1.5317 (18)
C4—H40.9300C12—C141.5318 (19)
C5—C61.3831 (17)C12—C131.5349 (18)
C5—C71.5067 (17)C13—H13A0.9600
C6—C151.383 (2)C13—H13B0.9600
C6—H60.9300C13—H13C0.9600
C7—N21.4598 (14)C14—H14A0.9600
C7—H7A0.9700C14—H14B0.9600
C7—H7B0.9700C14—H14C0.9600
C8—H8A0.9600C15—H150.9300
C8—H8B0.9600N1—O21.208 (2)
C8—H8C0.9600N1—O11.214 (2)
C9—C12i1.5317 (18)N3—H3A0.883 (15)
C9—H9A0.9700
N2—C1—C9112.95 (9)C11—C10—H10A108.6
N2—C1—C8113.69 (11)N2—C10—H10B108.6
C9—C1—C8109.55 (11)C11—C10—H10B108.6
N2—C1—H1106.7H10A—C10—H10B107.5
C9—C1—H1106.7N3—C11—C10112.80 (10)
C8—C1—H1106.7N3—C11—H11A109.0
C15—C2—C3122.80 (12)C10—C11—H11A109.0
C15—C2—N1118.71 (13)N3—C11—H11B109.0
C3—C2—N1118.47 (14)C10—C11—H11B109.0
C4—C3—C2117.93 (13)H11A—C11—H11B107.8
C4—C3—H3121.0N3—C12—C9i107.94 (9)
C2—C3—H3121.0N3—C12—C14113.61 (11)
C3—C4—C5120.98 (12)C9i—C12—C14110.55 (11)
C3—C4—H4119.5N3—C12—C13108.11 (11)
C5—C4—H4119.5C9i—C12—C13106.91 (11)
C6—C5—C4119.18 (11)C14—C12—C13109.47 (11)
C6—C5—C7122.20 (12)C12—C13—H13A109.5
C4—C5—C7118.62 (11)C12—C13—H13B109.5
C15—C6—C5120.86 (13)H13A—C13—H13B109.5
C15—C6—H6119.6C12—C13—H13C109.5
C5—C6—H6119.6H13A—C13—H13C109.5
N2—C7—C5110.45 (9)H13B—C13—H13C109.5
N2—C7—H7A109.6C12—C14—H14A109.5
C5—C7—H7A109.6C12—C14—H14B109.5
N2—C7—H7B109.6H14A—C14—H14B109.5
C5—C7—H7B109.6C12—C14—H14C109.5
H7A—C7—H7B108.1H14A—C14—H14C109.5
C1—C8—H8A109.5H14B—C14—H14C109.5
C1—C8—H8B109.5C2—C15—C6118.25 (12)
H8A—C8—H8B109.5C2—C15—H15120.9
C1—C8—H8C109.5C6—C15—H15120.9
H8A—C8—H8C109.5O2—N1—O1123.36 (15)
H8B—C8—H8C109.5O2—N1—C2118.46 (16)
C1—C9—C12i118.88 (10)O1—N1—C2118.18 (15)
C1—C9—H9A107.6C10—N2—C7113.41 (9)
C12i—C9—H9A107.6C10—N2—C1114.37 (9)
C1—C9—H9B107.6C7—N2—C1111.66 (10)
C12i—C9—H9B107.6C11—N3—C12115.96 (9)
H9A—C9—H9B107.0C11—N3—H3A109.2 (10)
N2—C10—C11114.82 (10)C12—N3—H3A108.6 (9)
N2—C10—H10A108.6
C15—C2—C3—C40.6 (2)C3—C2—N1—O2166.54 (16)
N1—C2—C3—C4177.77 (11)C15—C2—N1—O1164.41 (15)
C2—C3—C4—C50.19 (19)C3—C2—N1—O114.0 (2)
C3—C4—C5—C60.62 (18)C11—C10—N2—C760.07 (13)
C3—C4—C5—C7179.70 (11)C11—C10—N2—C1170.32 (10)
C4—C5—C6—C150.30 (19)C5—C7—N2—C10149.14 (10)
C7—C5—C6—C15179.97 (12)C5—C7—N2—C179.89 (13)
C6—C5—C7—N2118.14 (13)C9—C1—N2—C1071.93 (13)
C4—C5—C7—N261.53 (15)C8—C1—N2—C1053.70 (14)
N2—C1—C9—C12i66.10 (14)C9—C1—N2—C7157.59 (10)
C8—C1—C9—C12i166.07 (12)C8—C1—N2—C776.78 (13)
N2—C10—C11—N345.97 (15)C10—C11—N3—C12175.81 (10)
C3—C2—C15—C60.9 (2)C9i—C12—N3—C11176.37 (10)
N1—C2—C15—C6177.46 (12)C14—C12—N3—C1153.40 (15)
C5—C6—C15—C20.4 (2)C13—C12—N3—C1168.32 (14)
C15—C2—N1—O215.0 (2)
Symmetry code: (i) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N2i0.883 (17)2.284 (17)2.9770 (15)135.3 (15)
Symmetry code: (i) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N2i0.883 (17)2.284 (17)2.9770 (15)135.3 (15)
Symmetry code: (i) x, y+1, z.
 

Acknowledgements

The authors thank Professor D. Velmurugan, Centre for Advanced Study in Crystallography and Biophysics, University of Madras, for providing data-collection and computer facilities.

References

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First citationBruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
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