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

Journal logoIUCrDATA
ISSN: 2414-3146

(4Z)-4-(2-Oxo­propyl­­idene)-1,3-bis­­(prop-2-en-1-yl)-2,3,4,5-tetra­hydro-1H-1,5-benzodiazepin-2-one

aLaboratoire de Chimie Organique Hétérocyclique, URAC 21, Pôle de Compétence Pharmacochimie, Av Ibn Battouta, BP 1014, Faculté des Sciences, Mohammed V University, Rabat, Morocco, and bDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
*Correspondence e-mail: sebhaoui.jihad@gmail.com

Edited by J. Simpson, University of Otago, New Zealand (Received 27 March 2017; accepted 29 March 2017; online 4 April 2017)

In the title compound, C18H20N2O2, the diazepin-2-one ring adopts a tub conformation. The conformation of the acetyl group is partially determined by an intra­molecular N—H⋯O hydrogen bond. In the crystal, pairwise C—H⋯O hydrogen bonds form inversion dimers.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

1,5-Benzodiazepine derivatives have attracted much attention as they exhibit pronounced anxiolytic, sedative, hypnotic and anti­convulsant activities with low toxicity (Landquist et al., 1984[Landquist, J. K., Katritzky, A. R. & Rees, C. W. (1984). In Comprehensive Heterocyclic Chemistry, Vol. 1, pp. 166-170. Oxford: Pergamon.]; Hamor et al., 1984[Hamor, T. A. & Martin, I. I. (1984). Structure-activity relationships in a series of 5-phenyl-1,4-benzodiazepines. In X-ray crystallography and drug action edited by A. S. Horn & C. J. Ranter, pp. 275-301. Oxford: Clarendon press.]; Ben-Cherif et al., 2010[Ben-Cherif, W., Gharbi, R., Sebai, H., Dridi, D., Boughattas, N. A. & Ben-Attia, M. (2010). C. R. Biol. 333, 214-219.]). They are also used as an inter­mediates for the synthesis of new heterocyclic systems (Ahabchane et al., 2001[Ahabchane, N. H., Ibrahimi, S., Salem, M., Essassi, E. M., Amzazi, S. & Benjouad, A. (2001). C. R. Chem. 4, 917-924.]; Minnih et al., 2014[Minnih, M. S., Kandri Rodi, Y. & Essassi, E. M. (2014). J. Marocain. Chim. Heterocycl. 13, 1-24.]). In a continuation of our work on the synthesis and structure of 1,5-benzodiazepine derivatives (Sebhaoui et al., 2016[Sebhaoui, J., El Bakri, Y., Rayni, I., Essassi, E. M. & Mague, J. T. (2016). IUCrData, 1, x161013.]), we report here the preparation and crystal structure of the title compound.

The seven-membered ring adopts a tub conformation. Puckering analysis of the conformation gave the parameters Q(2) = 0.891 (1) Å, Q(3) = 0.295 (1) Å, φ(2) = 204.93 (7)° and φ(3) = 311.0 (2)° with a total puckering amplitude of 0.928 (1) Å. The orientation of the acetyl substituent is determined in part by the intra­molecular N1—H1⋯O2 hydrogen bond (Table 1[link] and Fig. 1[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2 0.910 (17) 1.878 (16) 2.6308 (12) 138.6 (14)
C10—H10⋯O1i 0.977 (14) 2.567 (14) 3.5316 (13) 168.9 (11)
Symmetry code: (i) -x+1, -y+2, -z+1.
[Figure 1]
Figure 1
The title mol­ecule with the labeling scheme and 50% probability ellipsoids. The intra­molecular hydrogen bond is shown as a dashed line.

In the crystal, mol­ecules form inversion dimers through complementary C10—H10⋯O1i hydrogen bonds (Table 1[link] and Fig. 2[link]).

[Figure 2]
Figure 2
Packing projected onto (001) with inter­molecular C—H⋯O hydrogen bonds shown as dashed lines.

Synthesis and crystallization

To a solution of (4Z)-4-(-2-oxo­propyl­idene)-1,5-benzodiazepin-2-one (0.01 mol) in 60 ml of N,N-di­methyl­formamide were added K2CO3 (0.02 mol), allyl bromide (0.02 mol) and tetra n-butyl­ammonium bromide (TBAB) (0.001 mol). The reaction mixture was stirred at room temperature for 48 h. The solution was filtered and the solvent removed under reduced pressure. The residue was chromatographed on a silica gel column using hexane and ethyl acetate (90/10) as eluents to afford the title compound as colourless crystals.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C18H20N2O2
Mr 296.36
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 100
a, b, c (Å) 8.6864 (6), 8.9925 (6), 10.9872 (7)
α, β, γ (°) 110.653 (1), 95.111 (1), 104.723 (1)
V3) 761.42 (9)
Z 2
Radiation type Mo Kα
μ (mm−1) 0.09
Crystal size (mm) 0.36 × 0.25 × 0.25
 
Data collection
Diffractometer Bruker SMART APEX CCD
Absorption correction Multi-scan (SADABS; Bruker, 2016[Bruker (2016). APEX3, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.88, 0.98
No. of measured, independent and observed [I > 2σ(I)] reflections 14767, 4041, 3219
Rint 0.026
(sin θ/λ)max−1) 0.685
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.128, 1.09
No. of reflections 4041
No. of parameters 279
H-atom treatment All H-atom parameters refined
Δρmax, Δρmin (e Å−3) 0.38, −0.24
Computer programs: APEX3 and SAINT (Bruker, 2016[Bruker (2016). APEX3, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2014/7 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND, Crystal Impact GbR, Bonn, Germany.])and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Structural data


Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

(4Z)-4-(2-Oxopropylidene)-1,3-bis(prop-2-en-1-yl)-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-one top
Crystal data top
C18H20N2O2Z = 2
Mr = 296.36F(000) = 316
Triclinic, P1Dx = 1.293 Mg m3
a = 8.6864 (6) ÅMo Kα radiation, λ = 0.71073 Å
b = 8.9925 (6) ÅCell parameters from 6420 reflections
c = 10.9872 (7) Åθ = 2.5–29.2°
α = 110.653 (1)°µ = 0.09 mm1
β = 95.111 (1)°T = 100 K
γ = 104.723 (1)°Block, colourless
V = 761.42 (9) Å30.36 × 0.25 × 0.25 mm
Data collection top
Bruker SMART APEX CCD
diffractometer
4041 independent reflections
Radiation source: fine-focus sealed tube3219 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
Detector resolution: 8.3333 pixels mm-1θmax = 29.2°, θmin = 2.0°
φ and ω scansh = 1111
Absorption correction: multi-scan
(SADABS; Bruker, 2016)
k = 1212
Tmin = 0.88, Tmax = 0.98l = 1415
14767 measured 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)] = 0.045Hydrogen site location: difference Fourier map
wR(F2) = 0.128All H-atom parameters refined
S = 1.09 w = 1/[σ2(Fo2) + (0.0798P)2 + 0.0641P]
where P = (Fo2 + 2Fc2)/3
4041 reflections(Δ/σ)max < 0.001
279 parametersΔρmax = 0.38 e Å3
0 restraintsΔρmin = 0.24 e Å3
Special details top

Experimental. The diffraction data were obtained from 3 sets of 400 frames, each of width 0.5° in ω, colllected at φ = 0.00, 90.00 and 180.00° and 2 sets of 800 frames, each of width 0.45° in φ, collected at ω = –30.00 and 210.00°. The scan time was 10 sec/frame.

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 > 2sigma(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
O10.72540 (10)0.99583 (9)0.37759 (8)0.01874 (19)
O20.68608 (10)0.68232 (10)0.74999 (8)0.0219 (2)
N10.73630 (11)0.63488 (11)0.50839 (9)0.0149 (2)
H10.7503 (19)0.6185 (19)0.5852 (17)0.033 (4)*
N20.86150 (10)0.80420 (10)0.33693 (9)0.0134 (2)
C10.87072 (12)0.64209 (12)0.32073 (10)0.0137 (2)
C20.95114 (13)0.56478 (14)0.22408 (11)0.0183 (2)
H20.9908 (17)0.6174 (17)0.1664 (14)0.020 (3)*
C30.97350 (14)0.41321 (15)0.21084 (12)0.0218 (3)
H31.0298 (19)0.3623 (19)0.1449 (16)0.032 (4)*
C40.91651 (14)0.33589 (14)0.29426 (12)0.0205 (2)
H40.9307 (18)0.2294 (19)0.2830 (15)0.031 (4)*
C50.83713 (13)0.41063 (13)0.39037 (11)0.0171 (2)
H50.7977 (16)0.3598 (16)0.4529 (14)0.018 (3)*
C60.81244 (12)0.56313 (13)0.40477 (10)0.0137 (2)
C70.62363 (12)0.71296 (12)0.50155 (10)0.0137 (2)
C80.58137 (12)0.72269 (13)0.36870 (10)0.0144 (2)
H80.5736 (17)0.6142 (17)0.2981 (14)0.022 (4)*
C90.72664 (12)0.85397 (13)0.36026 (10)0.0135 (2)
C100.55651 (13)0.77944 (13)0.60908 (11)0.0157 (2)
H100.4772 (17)0.8366 (17)0.5993 (14)0.022 (3)*
C110.59228 (13)0.76065 (13)0.73184 (11)0.0173 (2)
C120.51378 (16)0.83951 (17)0.84424 (12)0.0249 (3)
H12A0.469 (2)0.760 (2)0.881 (2)0.059 (6)*
H12B0.435 (2)0.891 (2)0.8239 (16)0.037 (4)*
H12C0.605 (2)0.933 (2)0.916 (2)0.051 (5)*
C130.42116 (13)0.75818 (14)0.34215 (11)0.0178 (2)
H13A0.3311 (17)0.6712 (17)0.3594 (14)0.023 (3)*
H13B0.4255 (16)0.8713 (17)0.4069 (14)0.021 (3)*
C140.38388 (15)0.74770 (17)0.20244 (13)0.0248 (3)
H140.399 (2)0.850 (3)0.190 (2)0.065 (6)*
C150.3403 (2)0.6128 (2)0.09694 (15)0.0432 (4)
H15A0.318 (3)0.505 (3)0.102 (3)0.097 (8)*
H15B0.318 (2)0.616 (2)0.0088 (19)0.050 (5)*
C161.00249 (13)0.92304 (13)0.32234 (11)0.0162 (2)
H16A1.0122 (16)1.0332 (17)0.3896 (13)0.017 (3)*
H16B1.0997 (17)0.8951 (17)0.3466 (13)0.023 (4)*
C170.99218 (14)0.92956 (14)0.18704 (11)0.0195 (2)
H171.0916 (19)1.0012 (19)0.1798 (15)0.033 (4)*
C180.86578 (16)0.85178 (15)0.08827 (12)0.0234 (3)
H18A0.762 (2)0.7781 (19)0.0972 (16)0.034 (4)*
H18B0.8730 (19)0.8666 (18)0.0047 (16)0.029 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0221 (4)0.0158 (4)0.0216 (4)0.0089 (3)0.0064 (3)0.0084 (3)
O20.0257 (4)0.0262 (4)0.0194 (4)0.0122 (3)0.0063 (3)0.0118 (3)
N10.0165 (4)0.0167 (4)0.0158 (4)0.0082 (3)0.0050 (3)0.0088 (4)
N20.0140 (4)0.0125 (4)0.0154 (4)0.0049 (3)0.0045 (3)0.0063 (3)
C10.0132 (5)0.0134 (5)0.0147 (5)0.0056 (4)0.0010 (4)0.0050 (4)
C20.0195 (5)0.0215 (5)0.0171 (5)0.0101 (4)0.0056 (4)0.0080 (4)
C30.0236 (6)0.0237 (6)0.0197 (6)0.0147 (5)0.0057 (4)0.0048 (4)
C40.0202 (5)0.0162 (5)0.0251 (6)0.0098 (4)0.0017 (4)0.0055 (4)
C50.0154 (5)0.0151 (5)0.0220 (6)0.0050 (4)0.0021 (4)0.0086 (4)
C60.0127 (4)0.0144 (5)0.0143 (5)0.0053 (4)0.0021 (4)0.0051 (4)
C70.0121 (5)0.0123 (4)0.0166 (5)0.0026 (4)0.0024 (4)0.0066 (4)
C80.0139 (5)0.0154 (5)0.0152 (5)0.0055 (4)0.0031 (4)0.0067 (4)
C90.0159 (5)0.0158 (5)0.0101 (5)0.0062 (4)0.0028 (4)0.0055 (4)
C100.0142 (5)0.0160 (5)0.0181 (5)0.0055 (4)0.0042 (4)0.0072 (4)
C110.0165 (5)0.0159 (5)0.0179 (5)0.0025 (4)0.0045 (4)0.0062 (4)
C120.0276 (6)0.0321 (7)0.0188 (6)0.0135 (5)0.0103 (5)0.0100 (5)
C130.0151 (5)0.0201 (5)0.0197 (5)0.0077 (4)0.0025 (4)0.0082 (4)
C140.0236 (6)0.0300 (6)0.0258 (6)0.0099 (5)0.0021 (5)0.0160 (5)
C150.0613 (10)0.0369 (8)0.0230 (7)0.0013 (7)0.0004 (7)0.0135 (6)
C160.0142 (5)0.0165 (5)0.0179 (5)0.0028 (4)0.0032 (4)0.0078 (4)
C170.0223 (6)0.0203 (5)0.0212 (6)0.0085 (4)0.0103 (4)0.0115 (4)
C180.0317 (6)0.0260 (6)0.0165 (6)0.0135 (5)0.0072 (5)0.0091 (5)
Geometric parameters (Å, º) top
O1—C91.2247 (13)C8—H80.991 (14)
O2—C111.2496 (14)C10—C111.4343 (16)
N1—C71.3527 (13)C10—H100.977 (14)
N1—C61.4081 (14)C11—C121.5070 (16)
N1—H10.910 (17)C12—H12A0.96 (2)
N2—C91.3701 (13)C12—H12B0.965 (17)
N2—C11.4290 (13)C12—H12C1.02 (2)
N2—C161.4690 (13)C13—C141.5047 (17)
C1—C21.3990 (15)C13—H13A1.039 (14)
C1—C61.4058 (15)C13—H13B1.003 (14)
C2—C31.3843 (16)C14—C151.287 (2)
C2—H20.954 (14)C14—H140.96 (2)
C3—C41.3871 (18)C15—H15A0.97 (3)
C3—H30.958 (16)C15—H15B0.983 (19)
C4—C51.3808 (16)C16—C171.5039 (16)
C4—H40.963 (15)C16—H16A0.982 (13)
C5—C61.3979 (15)C16—H16B0.980 (14)
C5—H50.991 (14)C17—C181.3170 (17)
C7—C101.3765 (15)C17—H170.966 (16)
C7—C81.5113 (15)C18—H18A1.010 (16)
C8—C91.5282 (14)C18—H18B0.979 (16)
C8—C131.5306 (14)
C7—N1—C6126.14 (9)C7—C10—C11122.55 (10)
C7—N1—H1113.1 (10)C7—C10—H10118.3 (8)
C6—N1—H1120.2 (10)C11—C10—H10119.0 (8)
C9—N2—C1124.02 (9)O2—C11—C10122.97 (10)
C9—N2—C16117.67 (9)O2—C11—C12118.49 (10)
C1—N2—C16118.26 (8)C10—C11—C12118.54 (10)
C2—C1—C6118.84 (10)C11—C12—H12A109.2 (12)
C2—C1—N2118.71 (9)C11—C12—H12B115.9 (10)
C6—C1—N2122.27 (9)H12A—C12—H12B111.7 (15)
C3—C2—C1120.93 (11)C11—C12—H12C106.4 (11)
C3—C2—H2119.7 (8)H12A—C12—H12C107.0 (16)
C1—C2—H2119.4 (8)H12B—C12—H12C106.3 (14)
C2—C3—C4120.12 (11)C14—C13—C8111.01 (9)
C2—C3—H3120.0 (9)C14—C13—H13A111.2 (8)
C4—C3—H3119.8 (9)C8—C13—H13A107.2 (8)
C5—C4—C3119.71 (10)C14—C13—H13B109.9 (8)
C5—C4—H4120.8 (9)C8—C13—H13B110.4 (8)
C3—C4—H4119.5 (9)H13A—C13—H13B106.9 (11)
C4—C5—C6121.04 (11)C15—C14—C13125.60 (13)
C4—C5—H5121.5 (8)C15—C14—H14116.5 (13)
C6—C5—H5117.4 (8)C13—C14—H14117.8 (13)
C5—C6—C1119.36 (10)C14—C15—H15A121.2 (16)
C5—C6—N1117.77 (10)C14—C15—H15B120.8 (10)
C1—C6—N1122.80 (9)H15A—C15—H15B117.7 (19)
N1—C7—C10121.64 (10)N2—C16—C17114.66 (9)
N1—C7—C8114.62 (9)N2—C16—H16A106.5 (8)
C10—C7—C8123.73 (9)C17—C16—H16A110.0 (8)
C7—C8—C9105.81 (8)N2—C16—H16B107.8 (8)
C7—C8—C13115.83 (9)C17—C16—H16B110.9 (8)
C9—C8—C13112.20 (9)H16A—C16—H16B106.5 (11)
C7—C8—H8108.3 (8)C18—C17—C16126.31 (11)
C9—C8—H8107.4 (8)C18—C17—H17122.1 (10)
C13—C8—H8106.9 (8)C16—C17—H17111.6 (10)
O1—C9—N2121.96 (10)C17—C18—H18A121.5 (9)
O1—C9—C8122.65 (9)C17—C18—H18B118.9 (9)
N2—C9—C8115.34 (9)H18A—C18—H18B119.6 (13)
C9—N2—C1—C2140.12 (10)N1—C7—C8—C13161.42 (9)
C16—N2—C1—C237.25 (14)C10—C7—C8—C1319.55 (14)
C9—N2—C1—C644.67 (15)C1—N2—C9—O1177.73 (9)
C16—N2—C1—C6137.96 (10)C16—N2—C9—O14.89 (15)
C6—C1—C2—C30.03 (16)C1—N2—C9—C80.13 (14)
N2—C1—C2—C3175.35 (10)C16—N2—C9—C8177.51 (9)
C1—C2—C3—C40.25 (18)C7—C8—C9—O1103.13 (11)
C2—C3—C4—C50.12 (18)C13—C8—C9—O124.08 (14)
C3—C4—C5—C60.29 (17)C7—C8—C9—N274.45 (11)
C4—C5—C6—C10.56 (16)C13—C8—C9—N2158.34 (9)
C4—C5—C6—N1177.52 (10)N1—C7—C10—C114.46 (16)
C2—C1—C6—C50.43 (15)C8—C7—C10—C11176.57 (10)
N2—C1—C6—C5174.78 (9)C7—C10—C11—O20.30 (17)
C2—C1—C6—N1177.22 (10)C7—C10—C11—C12179.43 (10)
N2—C1—C6—N12.01 (15)C7—C8—C13—C14174.24 (9)
C7—N1—C6—C5139.68 (11)C9—C8—C13—C1464.13 (12)
C7—N1—C6—C143.48 (15)C8—C13—C14—C1571.29 (18)
C6—N1—C7—C10179.89 (10)C9—N2—C16—C1781.22 (12)
C6—N1—C7—C80.83 (14)C1—N2—C16—C1796.32 (11)
N1—C7—C8—C973.60 (11)N2—C16—C17—C186.42 (17)
C10—C7—C8—C9105.44 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.910 (17)1.878 (16)2.6308 (12)138.6 (14)
C10—H10···O1i0.977 (14)2.567 (14)3.5316 (13)168.9 (11)
Symmetry code: (i) x+1, y+2, z+1.
 

Acknowledgements

JTM thanks Tulane University for support of the Tulane Crystallography Laboratory.

References

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