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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1729.
Published online 2010 June 23. doi:  10.1107/S1600536810023263
PMCID: PMC3006714

N-{2-[N-(4-Methyl­phen­yl)oxamo­yl]phen­yl}propanamide

Abstract

The title compound, C18H18N2O3, is the product of the heterocyclic ring cleavage at position 2 of 1-propionylisatin. Two centrosymmetric cyclic motifs, viz. R 2 2(14) and R 2 2(18), are formed by N—H(...)O hydrogen bonds with the propanamide and amino­phenyl units, respectively, as the N—H donors. These motifs combine into two C 2 2(8) chain motifs parallel to the b axis. The chain structure is stabilized by C—H(...)π inter­actions between the benzene rings, where C—H is from the phenyl ring of the cleaved part of 1-pro­pionylisatin.

Related literature

For related structures, see: Hohne & Seidel (1979 [triangle]); Boryczka et al. (1998 [triangle]); Zukerman-Schpector et al. (1994 [triangle]). For synthetic background, see: Pervez et al. (2009 [triangle], 2010a [triangle],b [triangle]). For graph-set notation, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1729-scheme1.jpg

Experimental

Crystal data

  • C18H18N2O3
  • M r = 310.34
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1729-efi1.jpg
  • a = 9.2048 (4) Å
  • b = 9.7717 (3) Å
  • c = 10.4404 (4) Å
  • α = 72.962 (2)°
  • β = 72.920 (1)°
  • γ = 69.285 (2)°
  • V = 820.63 (6) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 296 K
  • 0.32 × 0.24 × 0.22 mm

Data collection

  • Bruker Kappa APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.942, T max = 0.952
  • 11476 measured reflections
  • 2933 independent reflections
  • 2402 reflections with I > 2σ(I)
  • R int = 0.023

Refinement

  • R[F 2 > 2σ(F 2)] = 0.039
  • wR(F 2) = 0.111
  • S = 1.03
  • 2933 reflections
  • 210 parameters
  • H-atom parameters constrained
  • Δρmax = 0.18 e Å−3
  • Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810023263/gk2285sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810023263/gk2285Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

MA gratefully acknowledges the Higher Education Commission (HEC), Islamabad, Pakistan, for providing him with a Scholarship under the Indigenous PhD Program and also for partial funding of this research work.

supplementary crystallographic information

Comment

We recently have reported the synthesis and crystal structures of certain isatin derivatives (Pervez et al., 2009, 2010a, 2010b). The title compound (I), (Fig. 1) is the side product obtained in low yield due to the heterocyclic ring cleavage at position-2 of 1-propionylisatin when reacted with p-toluidine.

The crystal structures of (II) i.e. 2-oxo-N,2-diphenylacetamide (Boryczka et al., 1998) and (III) i.e. p-tolyl-glyoxylic acid p-chloroanilide (Hohne & Seidel, 1979) have been published. The crystal structure of (I) differs from (II) and (III) due to substituants at the phenyl rings. The crystal structure of (IV) i.e. 2'-(N-isopropyloxamoyl)acetanilide (Zukerman-Schpector et al., 1994) has been published, which has isopropyl instead of tolyl and methyl instead of ethyl when compared to (I).

In the crystal structure of (I), the tolylamino group A (C1—C7/N1) and B(C9–C15/N2) of the cleaved part of 1-propionylisatin are planar with r. m. s. deviation of 0.0364 and 0.0456 Å, respectively. The dihedral angle between A/B is 80.25 (5) °. There exist an S(5) ring motif (Bernstein et al., 1995) due to N—H···O interactions (Table 1). In the central part short intramolecular C═O···C═O contact replaces a hydrogen-bond plausible S(6). The central part of (I) has twisting flexibility to set the orientation of substituated phenyl rings. The intermolecular interactions of N—H···O and C—H···O types complete R22(12) and R22(18) ring motifs setting the two molecules in dimeric way. These dimers are interlinked through N—H···O interactions with R22(14) ring motif (Table 1, Fig. 2). The polymeric chain extends along the crystallographic b axis. The C—H···π interaction (Table 1) also play role in stabilizing the molecules.

Experimental

To a refluxing solution of 1-propionylisatin (1.02 g, 5 mmol) in ethanol (15 ml) containing 2–3 drops of concentrated sulfuric acid was added the solution of p-toluidine (0.54 g, 5 mmol) made in ethanol (5 ml). The reaction mixture was then refluxed for 2 h, after which it was left at room temperature overnight. The reddish yellow solid formed was collected by suction filtration, washing of which with ethanol to get rid of the soluble impurities, however, gave a dirty white solid. Recrystallization of the same from ethanol furnished the title heterocyclic ring cleavage product (I) in pure form (0.33 g, 21%) m.p. 423 K. The single crystals of (I) for x-ray analysis were grown in ethyl acetate-petroleum ether (1:4) by diffusion method at room temperature.

Refinement

The H-atoms were positioned geometrically (N–H = 0.86 Å, C–H = 0.93–0.97 Å) and refined as riding with Uiso(H) = xUeq(C, N), where x = 1.5 for methyl and x = 1.2 for all other H-atoms. !5

Figures

Fig. 1.
View of the title compound with the atom numbering scheme. The displacement ellipsoids are drawn at the 30% probability level. H-atoms are shown by small circles of arbitrary radii.
Fig. 2.
The partial packing (PLATON; Spek, 2009) which shows that molecules arranged via hydrogen bonds into one-dimensional polymeric chains extending along the b axis.

Crystal data

C18H18N2O3Z = 2
Mr = 310.34F(000) = 328
Triclinic, P1Dx = 1.254 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.2048 (4) ÅCell parameters from 2402 reflections
b = 9.7717 (3) Åθ = 2.8–25.3°
c = 10.4404 (4) ŵ = 0.09 mm1
α = 72.962 (2)°T = 296 K
β = 72.920 (1)°Prism, yellow
γ = 69.285 (2)°0.32 × 0.24 × 0.22 mm
V = 820.63 (6) Å3

Data collection

Bruker Kappa APEXII CCD diffractometer2933 independent reflections
Radiation source: fine-focus sealed tube2402 reflections with I > 2σ(I)
graphiteRint = 0.023
Detector resolution: 8.2 pixels mm-1θmax = 25.3°, θmin = 2.8°
ω scansh = −11→10
Absorption correction: multi-scan (SADABS; Bruker, 2005)k = −11→11
Tmin = 0.942, Tmax = 0.952l = −12→12
11476 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H-atom parameters constrained
S = 1.03w = 1/[σ2(Fo2) + (0.0538P)2 + 0.1939P] where P = (Fo2 + 2Fc2)/3
2933 reflections(Δ/σ)max < 0.001
210 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = −0.21 e Å3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles
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)

xyzUiso*/Ueq
O10.73296 (14)0.26832 (11)0.51591 (11)0.0532 (4)
O20.60422 (14)−0.02427 (11)0.72653 (12)0.0527 (4)
O30.36026 (15)0.18977 (12)0.55159 (12)0.0572 (4)
N10.73440 (15)0.06472 (13)0.45212 (13)0.0454 (4)
N20.36473 (15)0.41064 (13)0.57412 (12)0.0434 (4)
C10.81861 (17)0.09987 (16)0.31438 (16)0.0423 (5)
C20.7508 (2)0.11442 (19)0.20806 (17)0.0533 (6)
C30.8280 (2)0.1562 (2)0.07434 (18)0.0584 (6)
C40.9720 (2)0.18504 (18)0.04359 (18)0.0541 (6)
C51.0394 (2)0.1665 (2)0.15214 (19)0.0585 (6)
C60.96495 (19)0.12374 (19)0.28597 (18)0.0533 (6)
C71.0503 (3)0.2377 (3)−0.1028 (2)0.0789 (8)
C80.69138 (17)0.15593 (15)0.53889 (15)0.0396 (5)
C90.58882 (17)0.10771 (15)0.67838 (15)0.0404 (5)
C100.49283 (17)0.22541 (16)0.75877 (14)0.0394 (4)
C110.5065 (2)0.19194 (19)0.89436 (16)0.0503 (5)
C120.4344 (2)0.2961 (2)0.97574 (17)0.0606 (6)
C130.3468 (2)0.4365 (2)0.92194 (18)0.0619 (6)
C140.3263 (2)0.47161 (18)0.78955 (17)0.0513 (5)
C150.39731 (17)0.36707 (15)0.70660 (14)0.0390 (4)
C160.33857 (18)0.32494 (17)0.50734 (16)0.0444 (5)
C170.2851 (3)0.4048 (2)0.3751 (2)0.0701 (7)
C180.1504 (3)0.3664 (3)0.3605 (3)0.0991 (10)
H10.71043−0.018140.480380.0544*
H20.653360.096230.226150.0639*
H2A0.361150.501190.531380.0521*
H30.781580.165010.003160.0701*
H51.137480.183260.134210.0702*
H61.013200.110980.357120.0640*
H7A1.162360.18772−0.116880.1184*
H7B1.032710.34386−0.120980.1184*
H7C1.005490.21520−0.163590.1184*
H110.565930.096790.931070.0604*
H120.444980.271491.066270.0727*
H130.301030.508560.975270.0744*
H140.264060.566360.755140.0616*
H17A0.254680.511910.368840.0841*
H17B0.373800.380800.299370.0841*
H18A0.061590.390400.434660.1487*
H18B0.180840.261340.362320.1487*
H18C0.120980.422600.274930.1487*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0656 (7)0.0375 (6)0.0605 (7)−0.0269 (5)−0.0023 (5)−0.0126 (5)
O20.0635 (7)0.0321 (5)0.0596 (7)−0.0167 (5)−0.0155 (5)0.0002 (5)
O30.0757 (8)0.0411 (6)0.0698 (8)−0.0238 (5)−0.0319 (6)−0.0087 (5)
N10.0516 (8)0.0360 (6)0.0531 (8)−0.0213 (6)−0.0045 (6)−0.0122 (5)
N20.0566 (8)0.0321 (6)0.0465 (7)−0.0200 (5)−0.0182 (6)0.0002 (5)
C10.0417 (8)0.0338 (7)0.0522 (9)−0.0120 (6)−0.0048 (7)−0.0143 (6)
C20.0465 (9)0.0610 (10)0.0617 (11)−0.0255 (8)−0.0069 (8)−0.0191 (8)
C30.0581 (11)0.0693 (11)0.0555 (10)−0.0246 (9)−0.0114 (8)−0.0176 (8)
C40.0508 (10)0.0466 (9)0.0596 (10)−0.0144 (7)−0.0001 (8)−0.0152 (7)
C50.0408 (9)0.0644 (11)0.0714 (12)−0.0227 (8)−0.0031 (8)−0.0159 (9)
C60.0442 (9)0.0586 (10)0.0622 (11)−0.0185 (8)−0.0124 (8)−0.0147 (8)
C70.0777 (14)0.0777 (14)0.0698 (13)−0.0306 (11)0.0063 (11)−0.0111 (10)
C80.0420 (8)0.0293 (7)0.0491 (9)−0.0116 (6)−0.0126 (7)−0.0061 (6)
C90.0439 (8)0.0325 (7)0.0494 (9)−0.0153 (6)−0.0170 (7)−0.0032 (6)
C100.0423 (8)0.0368 (7)0.0419 (8)−0.0184 (6)−0.0089 (6)−0.0040 (6)
C110.0582 (10)0.0475 (9)0.0462 (9)−0.0181 (7)−0.0179 (8)−0.0013 (7)
C120.0765 (12)0.0680 (12)0.0415 (9)−0.0242 (10)−0.0147 (8)−0.0118 (8)
C130.0784 (13)0.0568 (10)0.0527 (10)−0.0194 (9)−0.0076 (9)−0.0215 (8)
C140.0591 (10)0.0386 (8)0.0556 (10)−0.0141 (7)−0.0101 (8)−0.0115 (7)
C150.0436 (8)0.0345 (7)0.0428 (8)−0.0189 (6)−0.0098 (6)−0.0039 (6)
C160.0481 (9)0.0417 (8)0.0497 (9)−0.0199 (7)−0.0148 (7)−0.0063 (7)
C170.0917 (14)0.0686 (12)0.0623 (12)−0.0303 (11)−0.0355 (11)−0.0043 (9)
C180.1088 (19)0.0778 (15)0.133 (2)−0.0164 (13)−0.0782 (18)−0.0158 (14)

Geometric parameters (Å, °)

O1—C81.2244 (19)C12—C131.371 (3)
O2—C91.2119 (18)C13—C141.376 (2)
O3—C161.228 (2)C14—C151.391 (2)
N1—C11.425 (2)C16—C171.501 (3)
N1—C81.3359 (19)C17—C181.475 (4)
N2—C151.4116 (19)C2—H20.9300
N2—C161.352 (2)C3—H30.9300
N1—H10.8600C5—H50.9300
N2—H2A0.8600C6—H60.9300
C1—C61.380 (3)C7—H7A0.9600
C1—C21.376 (2)C7—H7B0.9600
C2—C31.382 (2)C7—H7C0.9600
C3—C41.379 (3)C11—H110.9300
C4—C71.508 (3)C12—H120.9300
C4—C51.384 (3)C13—H130.9300
C5—C61.376 (3)C14—H140.9300
C8—C91.529 (2)C17—H17A0.9700
C9—C101.490 (2)C17—H17B0.9700
C10—C111.390 (2)C18—H18A0.9600
C10—C151.402 (2)C18—H18B0.9600
C11—C121.377 (2)C18—H18C0.9600
O1···N23.1213 (19)C3···H13i3.0000
O1···C63.027 (2)C6···H14i3.0100
O1···C153.138 (2)C8···H62.9700
O1···N2i2.8821 (16)C10···H7Avi3.0400
O2···N12.7678 (17)C11···H11iii3.0500
O2···O33.0986 (18)C11···H3vii2.9700
O3···C82.914 (2)C12···H3vii3.0600
O3···N1ii2.9247 (18)C15···H7Avi3.1000
O3···C102.930 (2)H1···O22.4600
O3···C92.577 (2)H1···O3ii2.1400
O3···N13.178 (2)H1···H18Bii2.5200
O3···O23.0986 (18)H2···O2ii2.5800
O1···H62.8200H2A···H142.4300
O1···H14i2.8200H2A···H17A2.1600
O1···H17Ai2.8000H2A···O1i2.0700
O1···H2Ai2.0700H2A···N2i2.7700
O2···H12iii2.8000H2A···H2Ai2.4400
O2···H12.4600H3···C11viii2.9700
O2···H112.6100H3···C12viii3.0600
O2···H2ii2.5800H3···H7C2.3700
O2···H5iv2.8800H5···H7A2.5500
O2···H18Bii2.6600H5···O2iv2.8800
O3···H18B2.7200H6···O12.8200
O3···H1ii2.1400H6···C82.9700
N1···O22.7678 (17)H6···H18Bix2.5000
N1···O33.178 (2)H7A···C10x3.0400
N1···O3ii2.9247 (18)H7A···C15x3.1000
N2···O13.1213 (19)H7A···H52.5500
N2···C83.157 (2)H7B···H18Cxi2.5900
N2···O1i2.8821 (16)H7C···H32.3700
N2···N2i3.298 (2)H11···O22.6100
N2···H2Ai2.7700H11···C11iii3.0500
C3···C4v3.572 (3)H11···H11iii2.4700
C3···C7v3.554 (3)H12···O2iii2.8000
C4···C3v3.572 (3)H13···C3i3.0000
C6···O13.027 (2)H14···H2A2.4300
C7···C3v3.554 (3)H14···O1i2.8200
C8···C163.146 (2)H14···C1i2.9900
C8···N23.157 (2)H14···C6i3.0100
C8···O32.914 (2)H17A···H2A2.1600
C9···C163.120 (2)H17A···O1i2.8000
C9···O32.577 (2)H18B···O32.7200
C10···O32.930 (2)H18B···H6xii2.5000
C15···O13.138 (2)H18B···O2ii2.6600
C16···C83.146 (2)H18B···H1ii2.5200
C16···C93.120 (2)H18C···H7Bxi2.5900
C1···H14i2.9900
C1—N1—C8122.33 (13)C16—C17—C18113.78 (19)
C15—N2—C16126.83 (13)C1—C2—H2120.00
C8—N1—H1119.00C3—C2—H2120.00
C1—N1—H1119.00C2—C3—H3119.00
C16—N2—H2A117.00C4—C3—H3119.00
C15—N2—H2A117.00C4—C5—H5119.00
C2—C1—C6119.50 (16)C6—C5—H5119.00
N1—C1—C6121.04 (15)C1—C6—H6120.00
N1—C1—C2119.43 (16)C5—C6—H6120.00
C1—C2—C3119.74 (18)C4—C7—H7A109.00
C2—C3—C4121.78 (18)C4—C7—H7B109.00
C3—C4—C7120.86 (19)C4—C7—H7C109.00
C5—C4—C7121.7 (2)H7A—C7—H7B109.00
C3—C4—C5117.39 (17)H7A—C7—H7C110.00
C4—C5—C6121.66 (19)H7B—C7—H7C109.00
C1—C6—C5119.89 (17)C10—C11—H11119.00
O1—C8—N1124.88 (14)C12—C11—H11119.00
N1—C8—C9115.40 (13)C11—C12—H12120.00
O1—C8—C9119.66 (13)C13—C12—H12120.00
O2—C9—C8119.57 (13)C12—C13—H13120.00
O2—C9—C10122.47 (14)C14—C13—H13120.00
C8—C9—C10117.22 (12)C13—C14—H14120.00
C11—C10—C15118.54 (14)C15—C14—H14120.00
C9—C10—C11116.22 (14)C16—C17—H17A109.00
C9—C10—C15125.18 (13)C16—C17—H17B109.00
C10—C11—C12121.67 (16)C18—C17—H17A109.00
C11—C12—C13119.31 (16)C18—C17—H17B109.00
C12—C13—C14120.45 (17)H17A—C17—H17B108.00
C13—C14—C15120.80 (16)C17—C18—H18A109.00
N2—C15—C10123.90 (13)C17—C18—H18B109.00
N2—C15—C14116.97 (13)C17—C18—H18C109.00
C10—C15—C14119.12 (14)H18A—C18—H18B109.00
O3—C16—C17122.47 (16)H18A—C18—H18C109.00
N2—C16—C17115.84 (14)H18B—C18—H18C109.00
O3—C16—N2121.68 (15)
C8—N1—C1—C2−118.93 (18)N1—C8—C9—C10−159.46 (15)
C8—N1—C1—C659.2 (2)O1—C8—C9—O2−147.04 (17)
C1—N1—C8—O1−8.3 (3)C8—C9—C10—C1547.4 (2)
C1—N1—C8—C9174.65 (14)O2—C9—C10—C1140.4 (2)
C15—N2—C16—O3−9.2 (3)O2—C9—C10—C15−142.61 (18)
C16—N2—C15—C1038.2 (3)C8—C9—C10—C11−129.66 (17)
C16—N2—C15—C14−140.31 (18)C15—C10—C11—C12−2.8 (3)
C15—N2—C16—C17172.10 (17)C9—C10—C15—N27.8 (3)
C2—C1—C6—C52.1 (3)C9—C10—C15—C14−173.71 (16)
N1—C1—C2—C3176.60 (15)C9—C10—C11—C12174.46 (17)
C6—C1—C2—C3−1.6 (3)C11—C10—C15—N2−175.24 (16)
N1—C1—C6—C5−176.03 (15)C11—C10—C15—C143.3 (3)
C1—C2—C3—C4−0.4 (3)C10—C11—C12—C130.0 (3)
C2—C3—C4—C7−177.02 (19)C11—C12—C13—C142.3 (3)
C2—C3—C4—C51.8 (3)C12—C13—C14—C15−1.8 (3)
C3—C4—C5—C6−1.2 (3)C13—C14—C15—N2177.53 (17)
C7—C4—C5—C6177.57 (19)C13—C14—C15—C10−1.1 (3)
C4—C5—C6—C1−0.7 (3)O3—C16—C17—C1847.0 (3)
O1—C8—C9—C1023.3 (2)N2—C16—C17—C18−134.27 (19)
N1—C8—C9—O230.2 (2)

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y, −z+1; (iii) −x+1, −y, −z+2; (iv) −x+2, −y, −z+1; (v) −x+2, −y, −z; (vi) x−1, y, z+1; (vii) x, y, z+1; (viii) x, y, z−1; (ix) x+1, y, z; (x) x+1, y, z−1; (xi) −x+1, −y+1, −z; (xii) x−1, y, z.

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of C1–C6 benzene ring.
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.862.462.7678 (17)102
N1—H1···O3ii0.862.142.9247 (18)152
N2—H2A···O1i0.862.072.8821 (16)157
C2—H2···O2ii0.932.583.506 (2)175
C14—H14···Cg1i0.932.893.6693 (18)142

Symmetry codes: (ii) −x+1, −y, −z+1; (i) −x+1, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: GK2285).

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