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ISSN: 2056-9890

3-Acetyl-2-methyl-4-(pyridin-3-yl)-1,4-di­hydro­indeno­[1,2-b]pyridin-5-one

aLatvian Institute of Organic Synthesis, 21 Aizkraukles street, Riga LV-1006, Latvia
*Correspondence e-mail: mishnevs@osi.lv

(Received 27 February 2013; accepted 9 April 2013; online 13 April 2013)

In the title compound, C20H16N2O2, the condensed tricyclic fragment is near to planar, with an r.m.s. deviation of 0.0531 Å. The 1,4-di­hydro­pyridine (1,4-DHP) ring adopts a slightly puckered boat-like conformation. The N and opposite C atoms deviate from the least-squares plane of the four other ring atoms by 0.039 (3) and 0.141 (3) Å, respectively. The C=O group located at the tricyclic fragment is fixed in an s-trans orientation, while the second C=O group adopts an s-cis orientation with respect to the double bonds of the 1,4-DHP ring. The pyridine ring has a pseudo-axial orientation with respect to the 1,4-DHP ring. The dihedral angle between the tricyclic system and the pyridine ring is 77.3 (3)°. In the crystal, the pyridine N atom accepts a hydrogen bond from the N—H group of the 1,4-DHP ring. The hydrogen bonds link the mol­ecules into infinite C(8) chains along the b-axis direction.

Related literature

For general information on the relationship between 1,4-di­hydro­pyridine ring substituents and pharmaceutical effects, see: Christopher et al. (2010[Christopher, G. E., Umesh, K. J., Leah, N. M., Dickey, A. C. & Gestwicki, J. E. (2010). Chem. Commun. 47, 529-531.]); Bisenieks et al. (1987[Bisenieks, E. A., Uldrikis, J. R., Duburs, G. J., Kozuhov, A. N., Neimane, D. U., Ivanov, E. B. & Merkusev, G. N. (1987). USSR Inventors Certif. No. 1324260.], 1995[Bisenieks, E. A., Uldrikis, J. R., Duburs, G. J., Tirzitis, G. D., Dauvarte, A. D., Zidermane, A. A. & Ponomareva, A. B. (1995). USSR Inventors Certif. No. 1050261.]); Ivanov et al. (1989[Ivanov, E. I., Ponamareva, T. V., Merkushev, G. N., Duburs, G. J., Bisenieks, E. A., Uldrikis, J. R. & Makarova, N. V. (1989). Abstract Book of the IXth Soviet-Indian Symposium on the Chemistry of Natural Products, Riga, May 15-18, 1989, pp. 87-88.]). For the synthesis of 1,4-DHP-containing tricyclic derivatives, see: Bisenieks et al. (1982[Bisenieks, E. A., Uldrikis, J. R., Kirule, I. E., Tirzitis, G. D. & Duburs, G. J. (1982). Chem. Heterocycl. Compd, 18, 1187-1189.]).

[Scheme 1]

Experimental

Crystal data
  • C20H16N2O2

  • Mr = 316.35

  • Triclinic, [P \overline 1]

  • a = 8.4361 (3) Å

  • b = 8.8812 (3) Å

  • c = 11.2582 (4) Å

  • α = 87.692 (2)°

  • β = 71.022 (2)°

  • γ = 89.210 (2)°

  • V = 797.00 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 190 K

  • 0.30 × 0.28 × 0.13 mm

Data collection
  • Nonius KappaCCD diffractometer

  • 5442 measured reflections

  • 3615 independent reflections

  • 2753 reflections with I > 2σ(I)

  • Rint = 0.020

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.124

  • S = 1.04

  • 3615 reflections

  • 219 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯N22i 0.86 2.06 2.916 (2) 175
Symmetry code: (i) x, y+1, z.

Data collection: COLLECT (Hooft, 1998[Hooft, R. (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and SCALEPACK; 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

3-Acetyl-2-methyl-4-pyridin-3-yl-1,4-dihydro-indeno[1,2-b]pyridin-5-one is a condensed tricyclic 1,4-dihydropyridine derivative containing a conjugated system, with an intense red colour which is common for this type of compounds. In this particular compound, the 1,4-dihydropyridine ring acts as a pharmacophore, and gives potentially useful pharmacological activities. Depending on the particular set of substituents, similar types of 1,4-dihydropyridine derivatives have been indentified as compounds possessing an effect on the accumulation of tau, a microtubule-binding protein, which plays a major role in many neurodegenerative disorders, including Alzheimer's disease (Christopher et al., 2010). It has been reported that similar types of 1,4-dihydropyridine derivatives have anti-cancer and anti-radiation activity (Bisenieks et al., 1995; Ivanov et al., 1989), and also skin regenerating and radioprotection properties (Bisenieks et al., 1987). Some of these types of compounds act as antioxidants (Bisenieks et al., 1982). Fig. 1 shows a view of the crystal structure of the title compound. In the crystal structure the 1,4-dihydropyridine (1,4-DHP) ring adopts a slightly puckered boat conformation. The N1 and C4 atoms deviate from the least-squares plane calculated through the four other ring atoms by 0.039 (3) Å and 0.141 (3) Å, respectively. The carbonyl group C13=O14 is fixed in trans orientation with respect to the double bonds of the 1,4-DHP ring while the second carbonyl group C15=O16 assumes cis orientation. The condensed tricyclic fragment is planar with an r.m.s. deviation of 0.0531 Å. The pyridine ring has an axial orientation with respect to the 1,4-DHP ring. A dihedral angle between the tricyclic system and the pyridine fragment is 77.3 (3)°. In the crystal, the pyridine nitrogen accepts a hydrogen bond from the N—H group of the 1,4-DHP cycle (Table 1). The hydrogen bonds essembles the molecules in infinite chains, C11(8), along the b axis.

Related literature top

For general information on the relationship between 1,4-dihydropyridine ring substituents and pharmaceutical effects, see: Christopher et al. (2010); Bisenieks et al. (1987, 1995); Ivanov et al. (1989). For the synthesis of 1,4-DHP-containing tricyclic derivatives, see: Bisenieks et al. (1982).

Experimental top

3-Acetyl-2-methyl-4-pyridin-3-yl-1,4-dihydro-indeno[1,2-b]pyridin-5-one was synthesized by the method described by Bisenieks et al. (1982). The resulting compound was dissolved in an acetic acid, DMAA and water (2:1:1) mixture while heating at 100 °C. Then the solution was kept at -5 °C until block crystals were obtained.

1H-NMR (400 MHz, DMSO-d6), δ/p.p.m.: 10.19 (s, 1H, N—H), 8.48–8.49 (m, 1H, py-2-H), 8.34–8.35 (m, 1H, py-6-H), 7.25–7.61 (m, 6H, py-4,5-H and –C6H4CO–), 4.96 (s, 1H, 4-H), 2.4 (s, 3H, COCH3), 2.12 (s, 3H, 2-CH3)

Refinement top

The H-atoms were included in the refinement at calculated positions (N—H = 0.86 Å, C—H = 0.93 to 0.98 Å) and refined using a riding-model approximation with Uiso(H)=1.2Ueq(NH,CH) and 1.5Ueq(CH3).

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound showing 50% probability elipsoids.
3-Acetyl-2-methyl-4-(pyridin-3-yl)-1,4-dihydroindeno[1,2-b]pyridin-5-one top
Crystal data top
C20H16N2O2Z = 2
Mr = 316.35F(000) = 332
Triclinic, P1Dx = 1.318 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.4361 (3) ÅCell parameters from 8654 reflections
b = 8.8812 (3) Åθ = 1.0–27.5°
c = 11.2582 (4) ŵ = 0.09 mm1
α = 87.692 (2)°T = 190 K
β = 71.022 (2)°Plate, red
γ = 89.210 (2)°0.30 × 0.28 × 0.13 mm
V = 797.00 (5) Å3
Data collection top
Nonius KappaCCD
diffractometer
2753 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.020
Graphite monochromatorθmax = 27.5°, θmin = 2.7°
CCD scansh = 1010
5442 measured reflectionsk = 1110
3615 independent reflectionsl = 1414
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-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0583P)2 + 0.1857P]
where P = (Fo2 + 2Fc2)/3
3615 reflections(Δ/σ)max < 0.001
219 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C20H16N2O2γ = 89.210 (2)°
Mr = 316.35V = 797.00 (5) Å3
Triclinic, P1Z = 2
a = 8.4361 (3) ÅMo Kα radiation
b = 8.8812 (3) ŵ = 0.09 mm1
c = 11.2582 (4) ÅT = 190 K
α = 87.692 (2)°0.30 × 0.28 × 0.13 mm
β = 71.022 (2)°
Data collection top
Nonius KappaCCD
diffractometer
2753 reflections with I > 2σ(I)
5442 measured reflectionsRint = 0.020
3615 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.124H-atom parameters constrained
S = 1.04Δρmax = 0.23 e Å3
3615 reflectionsΔρmin = 0.23 e Å3
219 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
N10.95378 (15)0.05051 (14)0.30285 (11)0.0282 (3)
H1A0.92470.14250.29480.034*
O140.77556 (15)0.36855 (13)0.58601 (11)0.0409 (3)
C50.90043 (17)0.18330 (16)0.41963 (13)0.0245 (3)
C60.86632 (17)0.03576 (16)0.40434 (13)0.0243 (3)
C230.9277 (2)0.53299 (17)0.30646 (16)0.0355 (4)
H30.96760.56030.37220.043*
N220.85901 (19)0.64053 (15)0.25866 (14)0.0424 (4)
C180.94286 (16)0.38372 (16)0.26401 (13)0.0237 (3)
C31.13273 (17)0.15786 (17)0.21807 (13)0.0258 (3)
C190.87866 (18)0.34450 (17)0.16849 (14)0.0287 (3)
H3A0.88500.24540.13730.034*
C151.27713 (18)0.22251 (19)0.11903 (15)0.0336 (4)
C41.02827 (17)0.26829 (16)0.32047 (13)0.0245 (3)
H71.10270.32180.35890.029*
C21.09093 (18)0.01006 (17)0.21154 (13)0.0279 (3)
C130.78546 (18)0.24006 (18)0.53979 (13)0.0287 (3)
O161.33862 (17)0.16140 (15)0.01533 (11)0.0523 (4)
C241.1816 (2)0.1054 (2)0.11276 (16)0.0412 (4)
H11A1.29930.08300.08440.062*
H11B1.16380.20360.14750.062*
H11C1.13970.10340.04310.062*
C200.80500 (19)0.45370 (19)0.11972 (15)0.0346 (4)
H120.76040.42870.05600.042*
C70.72519 (17)0.01618 (17)0.51290 (13)0.0274 (3)
C210.7984 (2)0.59916 (19)0.16626 (16)0.0372 (4)
H140.74980.67220.13220.045*
C120.67731 (18)0.10812 (18)0.59719 (14)0.0294 (3)
C80.64311 (19)0.15161 (19)0.53788 (15)0.0340 (4)
H160.67470.23410.48180.041*
C100.4653 (2)0.0398 (2)0.73495 (16)0.0434 (4)
H170.37820.04970.81020.052*
C90.5097 (2)0.1612 (2)0.65120 (16)0.0411 (4)
H180.45050.25110.66990.049*
C171.3462 (2)0.3722 (2)0.14648 (18)0.0454 (5)
H19A1.27080.45100.14400.068*
H19B1.35820.37250.22840.068*
H19C1.45360.38850.08460.068*
C110.54884 (19)0.0980 (2)0.70877 (15)0.0376 (4)
H200.51830.18030.76520.045*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0341 (6)0.0202 (6)0.0261 (6)0.0024 (5)0.0044 (5)0.0028 (5)
O140.0472 (7)0.0363 (7)0.0346 (6)0.0057 (5)0.0084 (5)0.0139 (5)
C50.0275 (7)0.0254 (8)0.0205 (7)0.0041 (6)0.0078 (6)0.0001 (6)
C60.0267 (7)0.0260 (8)0.0204 (7)0.0037 (5)0.0077 (6)0.0022 (6)
C230.0484 (9)0.0247 (8)0.0374 (9)0.0005 (7)0.0197 (7)0.0021 (7)
N220.0566 (9)0.0241 (7)0.0477 (9)0.0066 (6)0.0184 (7)0.0002 (6)
C180.0234 (6)0.0221 (7)0.0243 (7)0.0018 (5)0.0058 (5)0.0023 (6)
C30.0262 (7)0.0304 (8)0.0199 (7)0.0047 (6)0.0057 (6)0.0028 (6)
C190.0318 (7)0.0245 (8)0.0305 (8)0.0000 (6)0.0112 (6)0.0005 (6)
C150.0292 (7)0.0397 (9)0.0290 (8)0.0078 (6)0.0040 (6)0.0111 (7)
C40.0268 (7)0.0247 (7)0.0233 (7)0.0004 (5)0.0097 (6)0.0004 (6)
C20.0315 (7)0.0306 (8)0.0202 (7)0.0073 (6)0.0062 (6)0.0006 (6)
C130.0300 (7)0.0339 (9)0.0231 (7)0.0066 (6)0.0101 (6)0.0031 (6)
O160.0564 (8)0.0545 (8)0.0305 (7)0.0109 (6)0.0084 (6)0.0084 (6)
C240.0468 (9)0.0371 (10)0.0320 (9)0.0098 (8)0.0027 (7)0.0075 (7)
C200.0344 (8)0.0404 (9)0.0322 (8)0.0029 (7)0.0149 (7)0.0036 (7)
C70.0270 (7)0.0321 (8)0.0238 (7)0.0031 (6)0.0088 (6)0.0049 (6)
C210.0370 (8)0.0359 (9)0.0372 (9)0.0104 (7)0.0088 (7)0.0084 (7)
C120.0277 (7)0.0388 (9)0.0220 (7)0.0045 (6)0.0080 (6)0.0031 (6)
C80.0350 (8)0.0355 (9)0.0322 (8)0.0010 (6)0.0111 (7)0.0091 (7)
C100.0294 (8)0.0696 (13)0.0284 (9)0.0008 (8)0.0041 (7)0.0165 (9)
C90.0338 (8)0.0522 (11)0.0389 (9)0.0079 (7)0.0119 (7)0.0198 (8)
C170.0326 (8)0.0541 (12)0.0476 (10)0.0104 (7)0.0086 (8)0.0216 (9)
C110.0313 (8)0.0558 (11)0.0234 (8)0.0073 (7)0.0057 (6)0.0018 (7)
Geometric parameters (Å, º) top
N1—C61.3541 (18)C2—C241.500 (2)
N1—C21.3923 (19)C13—C121.507 (2)
N1—H1A0.8600C24—H11A0.9600
O14—C131.2274 (19)C24—H11B0.9600
C5—C61.354 (2)C24—H11C0.9600
C5—C131.459 (2)C20—C211.369 (2)
C5—C41.497 (2)C20—H120.9300
C6—C71.486 (2)C7—C81.372 (2)
C23—N221.340 (2)C7—C121.400 (2)
C23—C181.384 (2)C21—H140.9300
C23—H30.9300C12—C111.372 (2)
N22—C211.338 (2)C8—C91.405 (2)
C18—C191.3837 (19)C8—H160.9300
C18—C41.5312 (18)C10—C91.375 (3)
C3—C21.360 (2)C10—C111.398 (3)
C3—C151.485 (2)C10—H170.9300
C3—C41.529 (2)C9—H180.9300
C19—C201.382 (2)C17—H19A0.9600
C19—H3A0.9300C17—H19B0.9600
C15—O161.220 (2)C17—H19C0.9600
C15—C171.505 (2)C11—H200.9300
C4—H70.9800
C6—N1—C2119.88 (13)C2—C24—H11A109.5
C6—N1—H1A120.1C2—C24—H11B109.5
C2—N1—H1A120.1H11A—C24—H11B109.5
C6—C5—C13108.51 (13)C2—C24—H11C109.5
C6—C5—C4122.68 (13)H11A—C24—H11C109.5
C13—C5—C4128.66 (13)H11B—C24—H11C109.5
C5—C6—N1123.00 (13)C21—C20—C19119.23 (14)
C5—C6—C7111.18 (13)C21—C20—H12120.4
N1—C6—C7125.81 (13)C19—C20—H12120.4
N22—C23—C18124.02 (15)C8—C7—C12121.17 (14)
N22—C23—H3118.0C8—C7—C6132.56 (15)
C18—C23—H3118.0C12—C7—C6106.25 (13)
C21—N22—C23117.45 (14)N22—C21—C20122.67 (14)
C19—C18—C23117.09 (13)N22—C21—H14118.7
C19—C18—C4121.92 (13)C20—C21—H14118.7
C23—C18—C4120.99 (13)C11—C12—C7121.20 (15)
C2—C3—C15120.83 (13)C11—C12—C13130.70 (15)
C2—C3—C4122.57 (13)C7—C12—C13108.08 (13)
C15—C3—C4116.45 (13)C7—C8—C9117.61 (16)
C20—C19—C18119.51 (14)C7—C8—H16121.2
C20—C19—H3A120.2C9—C8—H16121.2
C18—C19—H3A120.2C9—C10—C11121.08 (15)
O16—C15—C3122.70 (16)C9—C10—H17119.5
O16—C15—C17118.81 (15)C11—C10—H17119.5
C3—C15—C17118.46 (14)C10—C9—C8121.05 (16)
C5—C4—C3109.63 (12)C10—C9—H18119.5
C5—C4—C18110.49 (11)C8—C9—H18119.5
C3—C4—C18110.48 (11)C15—C17—H19A109.5
C5—C4—H7108.7C15—C17—H19B109.5
C3—C4—H7108.7H19A—C17—H19B109.5
C18—C4—H7108.7C15—C17—H19C109.5
C3—C2—N1121.09 (13)H19A—C17—H19C109.5
C3—C2—C24126.54 (14)H19B—C17—H19C109.5
N1—C2—C24112.36 (13)C12—C11—C10117.86 (16)
O14—C13—C5127.98 (14)C12—C11—H20121.1
O14—C13—C12126.06 (14)C10—C11—H20121.1
C5—C13—C12105.96 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···N22i0.862.062.916 (2)175
Symmetry code: (i) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC20H16N2O2
Mr316.35
Crystal system, space groupTriclinic, P1
Temperature (K)190
a, b, c (Å)8.4361 (3), 8.8812 (3), 11.2582 (4)
α, β, γ (°)87.692 (2), 71.022 (2), 89.210 (2)
V3)797.00 (5)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.30 × 0.28 × 0.13
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
5442, 3615, 2753
Rint0.020
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.124, 1.04
No. of reflections3615
No. of parameters219
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.23, 0.23

Computer programs: COLLECT (Hooft, 1998), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···N22i0.862.062.916 (2)175
Symmetry code: (i) x, y+1, z.
 

Acknowledgements

The study was supported by the Latvian National Research Programme 2010–2013: "Development of prevention, treatment, diagnostic means, practices and biomedicine technologies for improvement of public health".

References

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