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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 3| March 2010| Pages o641-o642

6-(4-Bromo­phen­yl)-2-eth­­oxy-4-(2,4,5-tri­meth­oxy­phen­yl)nicotino­nitrile

aCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand, bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and cDepartment of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India
*Correspondence e-mail: suchada.c@psu.ac.th

(Received 26 January 2010; accepted 9 February 2010; online 17 February 2010)

There are two mol­ecules in the asymmetric unit of the title compound, C23H21BrN2O4, which differ in the conformation of their ethoxy residues, i.e. almost co-planar with the pyridine ring in one mol­ecule [C—O—C—C = −174.0 (2)°] but almost perpendicular in the other [C—O—C—C = 92.8 (3)°]. The dihedral angles between the central pyridine ring and the 4-bromo­phenyl and 2,4,5-trimethoxy­phenyl rings are 11.05 (12) and 63.78 (12)°, respectively, in one mol­ecule; the corres­ponding angles in the other mol­ecule are 30.38 (13) and 65.38 (13)°, respectively. In the crystal structure, pairs of mol­ecules are arranged in a face-to-face sandwich structure which further stacks along the b axis. The crystal packing features C—H⋯π inter­actions and Br⋯O [3.5417 (17) Å], Br⋯C [3.748 (3) Å], C⋯N [3.376 (4) Å] and C⋯O [3.351 (3)–3.409 (3) Å] contacts. Finally, ππ inter­actions [centroid⋯centroid distances = 3.6346 (19) and 3.6882 (19) Å] are observed.

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For the synthesis and applications of nicotinonitrile derivatives, see: Borgna et al. (1993[Borgna, P., Pregnolato, M., Gamba, I. A. & Mellerio, G. (1993). J. Heterocyclic Chem, 30, 1079-1084.]); Goda et al. (2004[Goda, F. E., Abdel-Aziz, A. A.-M. & Attef, O. A. (2004). Bioorg. Med. Chem. 12, 1845-1852.]). For related structures, see Chantrapromma et al. (2009[Chantrapromma, S., Fun, H.-K., Suwunwong, T., Padaki, M. & Isloor, A. M. (2009). Acta Cryst. E65, o2914-o2915.], 2010[Chantrapromma, S., Fun, H.-K., Suwunwong, T., Padaki, M. & Isloor, A. M. (2010). Acta Cryst. E66, o79-o80.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C23H21BrN2O4

  • Mr = 469.32

  • Triclinic, [P \overline 1]

  • a = 7.9631 (2) Å

  • b = 11.0499 (3) Å

  • c = 23.9690 (6) Å

  • α = 92.201 (1)°

  • β = 91.968 (1)°

  • γ = 99.586 (1)°

  • V = 2076.31 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.01 mm−1

  • T = 100 K

  • 0.59 × 0.10 × 0.05 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.384, Tmax = 0.899

  • 31800 measured reflections

  • 9488 independent reflections

  • 7074 reflections with I > 2σ(I)

  • Rint = 0.043

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.098

  • S = 1.07

  • 9488 reflections

  • 549 parameters

  • H-atom parameters constrained

  • Δρmax = 0.79 e Å−3

  • Δρmin = −0.38 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of C7A–C11A/N1A and C12A–C17A rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C22A—H22CCg2i 0.96 2.74 3.585 (3) 147
C22B—H22ECg1ii 0.96 2.68 3.511 (3) 145
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. 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 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Substituted pyridine derivatives have been claimed to have several biological activities (Borgna et al., 1993; Goda et al., 2004). We have previously reported the syntheses and crystal structures of the nicotinonitrile derivatives (Chantrapromma et al., 2009; 2010). In continuation of our research into the synthesis of antimicrobial agents, the title malononitrile derivative was synthesised and studied for its anti-bacterial activities. However, our results showed that the title compound does not possess anti-bacterial activities. Herein, we report the crystal structure of the title compound (I).

There are two crystallographic independent molecules A and B in the asymmetric unit of (I) (Fig. 1) with differences in conformation of the ethoxy group distinguishing them. In molecule A the ethoxy residue is almost co-planar with the pyridine ring [C11A–O1A–C18A–C19A = -174.0 (2) °] whereas it is almost perpendicular in molecule B [C11B–O1B–C18B–C19B = 92.8 (3) °]. The dihedral angles between the central pyridine ring and the 4-bromophenyl and 2,4,5-trimethoxyphenyl rings are 11.05 (12) and 63.78 (12) ° respectively in molecule A whereas the corresponding pair of angles in molecule B are 30.38 (13) and 65.38 (13) °. All three methoxy groups are nearly co-planar with the attached benzene ring [torsion angles C20–O2–C13–C14 = -11.6 (4) °, C21–O3–C15–C16 = 180.0 (2) ° and C22–O4–C16–C17 = 8.1 (4) ° in molecule A; and the corresponding values are -5.5 (4), -175.5 (2) and -7.7 (4) ° in molecule B]. Weak intramolecular C1A—H1AA···N1A (in molecule A) and C18B–H18C—N1B (in molecule B) interactions generate S(5) ring motifs (Bernstein et al., 1995). The bond distances are comparable with those in closely related structures (Chantrapromma et al., 2009; 2010).

In the crystal structure (Fig. 2), the molecules are arranged into a face-to-face sandwich-like structure which further stack along the b axis. The crystal is consolidated by C—H···π interactions (Table 1) and Br···O [3.5417 (17) Å], Br···C [3.748 (3) Å], C···N [3.376 (4) Å] and C···O [3.351 (3) - 3.409 (3) Å] contacts. Finally, π···π interactions with the distances of Cg1···Cg4 = 3.6346 (15) Å (symmetry code: 1-x, 1-y, 1-z) and Cg2···Cg3 = 3.6882 (15) Å (symmetry code: -x, 1-y, 1-z) are observed; Cg1, Cg2, Cg3 and Cg4 are the centroids of C7A–C11A/N1A, C12A–C17A, C7B–C11B/N1B, and C12B–C17B rings, respectively.

Related literature top

For hydrogen-bond motifs, see: Bernstein et al. (1995). For the synthesis and applications of nicotinonitrile derivatives, see: Borgna et al. (1993); Goda et al. (2004). For related structures, see Chantrapromma et al. (2009, 2010). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

(E)-1-(4-Bromophenyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (0.57 g, 0.0015 mol) was added with continuous stirring to a freshly prepared sodium alkoxide solution (0.0014 mol of sodium in 100 ml of ethanol). Malononitrile (1.3 g, 0.02 mol) was then added with continuous stirring at room temperature until the precipitate separated out. The resulting solid was filtered (yield 68 %). Colorless needle-shaped single crystals of the title compound were obtained by recrystallization from ethanol by the slow evaporation of the solvent at room temperature after several days, Mp. 460-461 K.

Refinement top

All H atoms were positioned geometrically and allowed to ride on their parent atoms, with d(C—H) = 0.93 Å for aromatic-H, 0.97 for CH2 and 0.96 Å for methyl-H atoms. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl-H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Intramolecular C—H···N interactions are shown as dashed lines.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the c axis.
6-(4-Bromophenyl)-2-ethoxy-4-(2,4,5-trimethoxyphenyl)nicotinonitrile top
Crystal data top
C23H21BrN2O4Z = 4
Mr = 469.32F(000) = 960
Triclinic, P1Dx = 1.501 Mg m3
Hall symbol: -P 1Melting point = 460–461 K
a = 7.9631 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.0499 (3) ÅCell parameters from 9488 reflections
c = 23.9690 (6) Åθ = 0.9–27.5°
α = 92.201 (1)°µ = 2.01 mm1
β = 91.968 (1)°T = 100 K
γ = 99.586 (1)°Needle, colorless
V = 2076.31 (9) Å30.59 × 0.10 × 0.05 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
9488 independent reflections
Radiation source: sealed tube7074 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.043
ϕ and ω scansθmax = 27.5°, θmin = 0.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1010
Tmin = 0.384, Tmax = 0.899k = 1414
31800 measured reflectionsl = 3131
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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0443P)2 + 0.7288P]
where P = (Fo2 + 2Fc2)/3
9488 reflections(Δ/σ)max = 0.001
549 parametersΔρmax = 0.79 e Å3
0 restraintsΔρmin = 0.38 e Å3
Crystal data top
C23H21BrN2O4γ = 99.586 (1)°
Mr = 469.32V = 2076.31 (9) Å3
Triclinic, P1Z = 4
a = 7.9631 (2) ÅMo Kα radiation
b = 11.0499 (3) ŵ = 2.01 mm1
c = 23.9690 (6) ÅT = 100 K
α = 92.201 (1)°0.59 × 0.10 × 0.05 mm
β = 91.968 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
9488 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
7074 reflections with I > 2σ(I)
Tmin = 0.384, Tmax = 0.899Rint = 0.043
31800 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.098H-atom parameters constrained
S = 1.07Δρmax = 0.79 e Å3
9488 reflectionsΔρmin = 0.38 e Å3
549 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
Br1A0.17700 (4)0.35388 (2)0.439858 (11)0.02094 (8)
O1A0.5666 (2)0.35133 (16)0.42626 (7)0.0190 (4)
O2A0.2036 (3)0.48545 (17)0.28313 (7)0.0229 (4)
O3A0.2540 (3)0.46349 (17)0.08142 (7)0.0227 (4)
O4A0.3749 (3)0.26013 (17)0.08836 (7)0.0211 (4)
N1A0.3634 (3)0.18217 (19)0.40057 (8)0.0161 (5)
N2A0.6447 (4)0.5362 (2)0.30967 (10)0.0304 (6)
C1A0.1472 (3)0.0213 (2)0.43550 (10)0.0171 (6)
H1AA0.21180.03410.46130.021*
C2A0.0518 (4)0.1272 (2)0.45413 (11)0.0183 (6)
H2AA0.05190.14340.49190.022*
C3A0.0433 (3)0.2081 (2)0.41548 (11)0.0160 (5)
C4A0.0472 (3)0.1856 (2)0.35901 (11)0.0177 (6)
H4AA0.11340.24110.33370.021*
C5A0.0488 (4)0.0796 (2)0.34091 (10)0.0179 (6)
H5AA0.04700.06390.30310.022*
C6A0.1488 (3)0.0047 (2)0.37885 (10)0.0145 (5)
C7A0.2528 (3)0.1189 (2)0.36092 (10)0.0153 (5)
C8A0.2379 (3)0.1613 (2)0.30754 (10)0.0157 (5)
H8AA0.16370.11540.28090.019*
C9A0.3339 (4)0.2727 (2)0.29383 (10)0.0163 (5)
C10A0.4480 (3)0.3366 (2)0.33414 (10)0.0160 (5)
C11A0.4564 (3)0.2863 (2)0.38748 (10)0.0158 (5)
C12A0.3084 (3)0.3240 (2)0.23801 (10)0.0166 (6)
C13A0.2479 (3)0.4339 (2)0.23373 (11)0.0183 (6)
C14A0.2272 (3)0.4832 (2)0.18187 (11)0.0186 (6)
H14A0.18540.55660.17930.022*
C15A0.2695 (3)0.4223 (2)0.13403 (10)0.0180 (6)
C16A0.3318 (3)0.3113 (2)0.13770 (10)0.0180 (6)
C17A0.3479 (3)0.2623 (2)0.18950 (10)0.0166 (5)
H17A0.38560.18730.19200.020*
C18A0.5755 (4)0.2961 (2)0.48023 (10)0.0206 (6)
H18A0.62190.22050.47640.025*
H18B0.46250.27700.49490.025*
C19A0.6888 (4)0.3869 (3)0.51911 (11)0.0244 (6)
H19A0.69600.35310.55520.037*
H19B0.64230.46150.52240.037*
H19C0.80070.40420.50450.037*
C20A0.1635 (5)0.6051 (3)0.28312 (13)0.0425 (9)
H20A0.14070.63070.32040.064*
H20B0.06450.60530.25910.064*
H20C0.25790.66070.26980.064*
C21A0.1906 (4)0.5766 (3)0.07668 (12)0.0281 (7)
H21A0.18010.59450.03800.042*
H21B0.26830.64180.09600.042*
H21C0.08100.56950.09290.042*
C22A0.4189 (4)0.1406 (2)0.09113 (11)0.0243 (6)
H22A0.44280.11170.05440.036*
H22B0.32560.08540.10530.036*
H22C0.51790.14400.11550.036*
C23A0.5564 (4)0.4488 (3)0.32183 (10)0.0215 (6)
Br1B0.38606 (4)0.11796 (3)0.926074 (11)0.02560 (9)
O1B0.0191 (3)0.84937 (17)0.92736 (7)0.0231 (4)
O2B0.4260 (3)0.98663 (17)0.78188 (7)0.0240 (4)
O3B0.2913 (3)0.96201 (16)0.58180 (7)0.0210 (4)
O4B0.0815 (3)0.75855 (16)0.59168 (7)0.0209 (4)
N1B0.1491 (3)0.68209 (19)0.90306 (8)0.0164 (5)
N2B0.0051 (3)1.0323 (2)0.81419 (10)0.0279 (6)
C1B0.3117 (4)0.4800 (2)0.93221 (11)0.0199 (6)
H1BA0.31840.54360.95920.024*
C2B0.3487 (4)0.3679 (2)0.94771 (11)0.0202 (6)
H2BA0.38000.35560.98450.024*
C3B0.3378 (4)0.2743 (2)0.90675 (11)0.0199 (6)
C4B0.2924 (4)0.2911 (3)0.85171 (11)0.0230 (6)
H4BA0.28500.22700.82500.028*
C5B0.2584 (4)0.4043 (2)0.83709 (11)0.0226 (6)
H5BA0.23100.41700.80000.027*
C6B0.2645 (3)0.5004 (2)0.87740 (10)0.0173 (6)
C7B0.2157 (3)0.6191 (2)0.86213 (11)0.0178 (6)
C8B0.2394 (4)0.6627 (2)0.80881 (10)0.0187 (6)
H8BA0.28540.61670.78180.022*
C9B0.1946 (3)0.7745 (2)0.79583 (10)0.0165 (5)
C10B0.1183 (3)0.8366 (2)0.83705 (10)0.0179 (6)
C11B0.0976 (4)0.7856 (2)0.88999 (10)0.0179 (6)
C12B0.2257 (3)0.8253 (2)0.74001 (10)0.0164 (5)
C13B0.3413 (4)0.9333 (2)0.73404 (11)0.0185 (6)
C14B0.3669 (4)0.9808 (2)0.68134 (10)0.0178 (6)
H14B0.44431.05260.67740.021*
C15B0.2768 (4)0.9209 (2)0.63469 (10)0.0170 (6)
C16B0.1637 (3)0.8103 (2)0.64004 (10)0.0160 (5)
C17B0.1417 (3)0.7636 (2)0.69231 (10)0.0172 (6)
H17B0.06930.68930.69590.021*
C18B0.0121 (4)0.8016 (3)0.98201 (11)0.0262 (7)
H18C0.02370.71270.97960.031*
H18D0.11790.82270.99510.031*
C19B0.1320 (5)0.8537 (3)1.02274 (13)0.0367 (8)
H19D0.10530.82621.05940.055*
H19E0.14810.94181.02330.055*
H19F0.23460.82651.01150.055*
C20B0.5570 (4)1.0900 (3)0.77626 (12)0.0278 (7)
H20D0.61111.11530.81220.042*
H20E0.50811.15640.76140.042*
H20F0.64001.06790.75140.042*
C21B0.4143 (4)1.0690 (3)0.57435 (11)0.0233 (6)
H21D0.41661.08680.53550.035*
H21E0.52481.05500.58710.035*
H21F0.38451.13730.59550.035*
C22B0.0187 (4)0.6395 (2)0.59614 (11)0.0227 (6)
H22D0.06870.61010.56010.034*
H22E0.10740.64470.62180.034*
H22F0.05260.58390.60950.034*
C23B0.0514 (4)0.9469 (3)0.82524 (11)0.0212 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br1A0.02292 (16)0.01573 (13)0.02271 (14)0.00184 (12)0.00184 (12)0.00381 (10)
O1A0.0229 (11)0.0180 (9)0.0136 (8)0.0040 (8)0.0027 (8)0.0030 (7)
O2A0.0305 (12)0.0210 (10)0.0184 (9)0.0076 (9)0.0038 (9)0.0017 (8)
O3A0.0238 (11)0.0271 (10)0.0185 (9)0.0066 (9)0.0006 (8)0.0092 (8)
O4A0.0245 (11)0.0247 (10)0.0153 (9)0.0070 (9)0.0012 (8)0.0012 (7)
N1A0.0153 (12)0.0162 (11)0.0161 (10)0.0003 (10)0.0009 (9)0.0014 (8)
N2A0.0366 (16)0.0297 (14)0.0200 (12)0.0087 (13)0.0015 (12)0.0031 (10)
C1A0.0157 (14)0.0176 (13)0.0175 (12)0.0016 (11)0.0003 (11)0.0007 (10)
C2A0.0217 (15)0.0186 (13)0.0148 (12)0.0041 (12)0.0008 (11)0.0024 (10)
C3A0.0123 (13)0.0121 (12)0.0238 (13)0.0014 (11)0.0036 (11)0.0034 (10)
C4A0.0135 (14)0.0179 (13)0.0209 (13)0.0015 (11)0.0005 (11)0.0030 (10)
C5A0.0205 (15)0.0185 (13)0.0144 (12)0.0022 (12)0.0001 (11)0.0003 (10)
C6A0.0080 (13)0.0162 (12)0.0194 (12)0.0023 (11)0.0006 (11)0.0022 (10)
C7A0.0127 (13)0.0165 (12)0.0175 (12)0.0046 (11)0.0026 (11)0.0007 (10)
C8A0.0135 (14)0.0171 (12)0.0159 (12)0.0018 (11)0.0023 (11)0.0012 (10)
C9A0.0173 (14)0.0178 (13)0.0148 (12)0.0050 (11)0.0024 (11)0.0010 (10)
C10A0.0112 (13)0.0176 (13)0.0187 (12)0.0006 (11)0.0009 (11)0.0012 (10)
C11A0.0114 (13)0.0189 (13)0.0170 (12)0.0030 (11)0.0006 (11)0.0006 (10)
C12A0.0163 (14)0.0165 (12)0.0156 (12)0.0017 (11)0.0009 (11)0.0023 (10)
C13A0.0146 (14)0.0190 (13)0.0200 (13)0.0000 (12)0.0011 (11)0.0011 (10)
C14A0.0165 (14)0.0165 (13)0.0232 (13)0.0031 (12)0.0014 (12)0.0040 (10)
C15A0.0151 (14)0.0206 (13)0.0169 (12)0.0026 (12)0.0003 (11)0.0054 (10)
C16A0.0143 (14)0.0199 (13)0.0184 (13)0.0009 (12)0.0012 (11)0.0001 (10)
C17A0.0131 (14)0.0170 (12)0.0183 (12)0.0012 (11)0.0010 (11)0.0011 (10)
C18A0.0254 (16)0.0215 (13)0.0142 (12)0.0011 (13)0.0005 (12)0.0065 (10)
C19A0.0235 (16)0.0273 (15)0.0206 (14)0.0011 (13)0.0028 (12)0.0032 (11)
C20A0.071 (3)0.0301 (17)0.0321 (17)0.0255 (19)0.0053 (18)0.0008 (14)
C21A0.0297 (18)0.0338 (16)0.0237 (14)0.0107 (15)0.0022 (13)0.0138 (12)
C22A0.0315 (18)0.0239 (14)0.0173 (13)0.0054 (14)0.0009 (13)0.0013 (11)
C23A0.0262 (16)0.0238 (14)0.0126 (12)0.0010 (13)0.0007 (12)0.0013 (11)
Br1B0.03322 (19)0.02264 (15)0.02261 (14)0.00896 (13)0.00077 (13)0.00399 (11)
O1B0.0277 (12)0.0230 (10)0.0192 (9)0.0039 (9)0.0058 (9)0.0030 (8)
O2B0.0216 (11)0.0272 (10)0.0189 (9)0.0078 (9)0.0012 (8)0.0018 (8)
O3B0.0241 (11)0.0224 (10)0.0155 (9)0.0003 (9)0.0016 (8)0.0065 (7)
O4B0.0233 (11)0.0212 (9)0.0160 (9)0.0030 (9)0.0007 (8)0.0027 (7)
N1B0.0122 (11)0.0194 (11)0.0160 (10)0.0021 (10)0.0012 (9)0.0011 (9)
N2B0.0287 (15)0.0261 (13)0.0282 (13)0.0037 (12)0.0045 (11)0.0023 (10)
C1B0.0195 (15)0.0201 (13)0.0186 (13)0.0010 (12)0.0011 (12)0.0008 (10)
C2B0.0182 (15)0.0256 (14)0.0164 (12)0.0018 (12)0.0012 (12)0.0048 (11)
C3B0.0167 (15)0.0202 (13)0.0234 (14)0.0036 (12)0.0023 (12)0.0050 (11)
C4B0.0270 (17)0.0222 (14)0.0199 (13)0.0047 (13)0.0020 (12)0.0021 (11)
C5B0.0273 (16)0.0260 (14)0.0144 (12)0.0039 (13)0.0003 (12)0.0038 (11)
C6B0.0147 (14)0.0196 (13)0.0163 (12)0.0016 (11)0.0016 (11)0.0018 (10)
C7B0.0121 (14)0.0210 (13)0.0187 (13)0.0020 (11)0.0019 (11)0.0018 (10)
C8B0.0164 (14)0.0224 (14)0.0166 (12)0.0014 (12)0.0019 (11)0.0003 (10)
C9B0.0108 (13)0.0213 (13)0.0149 (12)0.0041 (11)0.0025 (10)0.0033 (10)
C10B0.0138 (14)0.0205 (13)0.0179 (12)0.0015 (12)0.0023 (11)0.0032 (10)
C11B0.0170 (14)0.0181 (13)0.0160 (12)0.0037 (12)0.0008 (11)0.0013 (10)
C12B0.0141 (14)0.0181 (13)0.0172 (12)0.0027 (11)0.0007 (11)0.0038 (10)
C13B0.0163 (14)0.0203 (13)0.0186 (13)0.0025 (12)0.0009 (11)0.0015 (10)
C14B0.0159 (14)0.0165 (13)0.0210 (13)0.0019 (11)0.0024 (11)0.0040 (10)
C15B0.0186 (15)0.0186 (13)0.0156 (12)0.0063 (12)0.0038 (11)0.0051 (10)
C16B0.0099 (13)0.0196 (13)0.0191 (13)0.0041 (11)0.0012 (11)0.0001 (10)
C17B0.0148 (14)0.0164 (12)0.0205 (13)0.0012 (11)0.0035 (11)0.0049 (10)
C18B0.0331 (18)0.0266 (15)0.0195 (13)0.0043 (14)0.0077 (13)0.0036 (11)
C19B0.049 (2)0.0237 (15)0.0343 (17)0.0022 (16)0.0071 (16)0.0035 (13)
C20B0.0288 (18)0.0264 (15)0.0237 (14)0.0074 (14)0.0019 (13)0.0040 (12)
C21B0.0173 (15)0.0282 (15)0.0238 (14)0.0005 (13)0.0019 (12)0.0110 (12)
C22B0.0263 (16)0.0195 (13)0.0205 (13)0.0015 (13)0.0006 (12)0.0001 (11)
C23B0.0206 (15)0.0254 (15)0.0153 (13)0.0024 (13)0.0013 (12)0.0012 (11)
Geometric parameters (Å, º) top
Br1A—C3A1.901 (2)Br1B—C3B1.902 (3)
O1A—C11A1.354 (3)O1B—C11B1.352 (3)
O1A—C18A1.456 (3)O1B—C18B1.445 (3)
O2A—C13A1.377 (3)O2B—C13B1.371 (3)
O2A—C20A1.411 (3)O2B—C20B1.427 (3)
O3A—C15A1.366 (3)O3B—C15B1.365 (3)
O3A—C21A1.431 (3)O3B—C21B1.425 (3)
O4A—C16A1.370 (3)O4B—C16B1.368 (3)
O4A—C22A1.426 (3)O4B—C22B1.430 (3)
N1A—C11A1.316 (3)N1B—C11B1.322 (3)
N1A—C7A1.362 (3)N1B—C7B1.354 (3)
N2A—C23A1.150 (3)N2B—C23B1.147 (4)
C1A—C2A1.384 (4)C1B—C2B1.381 (4)
C1A—C6A1.398 (3)C1B—C6B1.391 (3)
C1A—H1AA0.9300C1B—H1BA0.9300
C2A—C3A1.376 (4)C2B—C3B1.388 (4)
C2A—H2AA0.9300C2B—H2BA0.9300
C3A—C4A1.386 (4)C3B—C4B1.383 (4)
C4A—C5A1.381 (4)C4B—C5B1.379 (4)
C4A—H4AA0.9300C4B—H4BA0.9300
C5A—C6A1.402 (3)C5B—C6B1.402 (4)
C5A—H5AA0.9300C5B—H5BA0.9300
C6A—C7A1.477 (4)C6B—C7B1.485 (4)
C7A—C8A1.387 (3)C7B—C8B1.391 (3)
C8A—C9A1.393 (4)C8B—C9B1.385 (4)
C8A—H8AA0.9300C8B—H8BA0.9300
C9A—C10A1.390 (4)C9B—C10B1.394 (4)
C9A—C12A1.494 (3)C9B—C12B1.484 (3)
C10A—C11A1.417 (3)C10B—C11B1.412 (3)
C10A—C23A1.435 (4)C10B—C23B1.443 (4)
C12A—C13A1.384 (4)C12B—C13B1.396 (4)
C12A—C17A1.398 (4)C12B—C17B1.399 (4)
C13A—C14A1.392 (4)C13B—C14B1.395 (3)
C14A—C15A1.387 (4)C14B—C15B1.390 (4)
C14A—H14A0.9300C14B—H14B0.9300
C15A—C16A1.402 (4)C15B—C16B1.406 (4)
C16A—C17A1.384 (3)C16B—C17B1.379 (3)
C17A—H17A0.9300C17B—H17B0.9300
C18A—C19A1.503 (4)C18B—C19B1.504 (4)
C18A—H18A0.9700C18B—H18C0.9700
C18A—H18B0.9700C18B—H18D0.9700
C19A—H19A0.9600C19B—H19D0.9600
C19A—H19B0.9600C19B—H19E0.9600
C19A—H19C0.9600C19B—H19F0.9600
C20A—H20A0.9600C20B—H20D0.9600
C20A—H20B0.9600C20B—H20E0.9600
C20A—H20C0.9600C20B—H20F0.9600
C21A—H21A0.9600C21B—H21D0.9600
C21A—H21B0.9600C21B—H21E0.9600
C21A—H21C0.9600C21B—H21F0.9600
C22A—H22A0.9600C22B—H22D0.9600
C22A—H22B0.9600C22B—H22E0.9600
C22A—H22C0.9600C22B—H22F0.9600
C11A—O1A—C18A115.60 (19)C11B—O1B—C18B119.1 (2)
C13A—O2A—C20A118.5 (2)C13B—O2B—C20B117.6 (2)
C15A—O3A—C21A116.7 (2)C15B—O3B—C21B117.0 (2)
C16A—O4A—C22A115.9 (2)C16B—O4B—C22B115.60 (19)
C11A—N1A—C7A118.5 (2)C11B—N1B—C7B117.5 (2)
C2A—C1A—C6A121.6 (2)C2B—C1B—C6B121.9 (2)
C2A—C1A—H1AA119.2C2B—C1B—H1BA119.1
C6A—C1A—H1AA119.2C6B—C1B—H1BA119.1
C3A—C2A—C1A118.5 (2)C1B—C2B—C3B118.1 (2)
C3A—C2A—H2AA120.8C1B—C2B—H2BA121.0
C1A—C2A—H2AA120.8C3B—C2B—H2BA121.0
C2A—C3A—C4A121.9 (2)C4B—C3B—C2B121.9 (2)
C2A—C3A—Br1A119.47 (19)C4B—C3B—Br1B118.4 (2)
C4A—C3A—Br1A118.59 (19)C2B—C3B—Br1B119.7 (2)
C5A—C4A—C3A119.0 (2)C5B—C4B—C3B119.0 (2)
C5A—C4A—H4AA120.5C5B—C4B—H4BA120.5
C3A—C4A—H4AA120.5C3B—C4B—H4BA120.5
C4A—C5A—C6A120.9 (2)C4B—C5B—C6B120.9 (2)
C4A—C5A—H5AA119.6C4B—C5B—H5BA119.6
C6A—C5A—H5AA119.6C6B—C5B—H5BA119.6
C1A—C6A—C5A118.1 (2)C1B—C6B—C5B118.3 (2)
C1A—C6A—C7A119.7 (2)C1B—C6B—C7B121.1 (2)
C5A—C6A—C7A122.3 (2)C5B—C6B—C7B120.6 (2)
N1A—C7A—C8A121.5 (2)N1B—C7B—C8B122.5 (2)
N1A—C7A—C6A115.7 (2)N1B—C7B—C6B116.2 (2)
C8A—C7A—C6A122.7 (2)C8B—C7B—C6B121.3 (2)
C7A—C8A—C9A120.1 (2)C9B—C8B—C7B120.1 (2)
C7A—C8A—H8AA119.9C9B—C8B—H8BA119.9
C9A—C8A—H8AA119.9C7B—C8B—H8BA119.9
C10A—C9A—C8A118.3 (2)C8B—C9B—C10B117.4 (2)
C10A—C9A—C12A121.2 (2)C8B—C9B—C12B121.1 (2)
C8A—C9A—C12A120.5 (2)C10B—C9B—C12B121.5 (2)
C9A—C10A—C11A118.0 (2)C9B—C10B—C11B118.8 (2)
C9A—C10A—C23A121.0 (2)C9B—C10B—C23B121.1 (2)
C11A—C10A—C23A121.0 (2)C11B—C10B—C23B120.0 (2)
N1A—C11A—O1A119.7 (2)N1B—C11B—O1B121.1 (2)
N1A—C11A—C10A123.5 (2)N1B—C11B—C10B123.4 (2)
O1A—C11A—C10A116.8 (2)O1B—C11B—C10B115.5 (2)
C13A—C12A—C17A119.3 (2)C13B—C12B—C17B119.0 (2)
C13A—C12A—C9A120.6 (2)C13B—C12B—C9B120.9 (2)
C17A—C12A—C9A120.1 (2)C17B—C12B—C9B120.1 (2)
O2A—C13A—C12A115.6 (2)O2B—C13B—C14B123.4 (2)
O2A—C13A—C14A123.6 (2)O2B—C13B—C12B116.5 (2)
C12A—C13A—C14A120.7 (2)C14B—C13B—C12B120.1 (2)
C15A—C14A—C13A119.6 (2)C15B—C14B—C13B120.1 (2)
C15A—C14A—H14A120.2C15B—C14B—H14B120.0
C13A—C14A—H14A120.2C13B—C14B—H14B120.0
O3A—C15A—C14A123.9 (2)O3B—C15B—C14B124.0 (2)
O3A—C15A—C16A115.8 (2)O3B—C15B—C16B115.7 (2)
C14A—C15A—C16A120.4 (2)C14B—C15B—C16B120.3 (2)
O4A—C16A—C17A124.8 (2)O4B—C16B—C17B125.3 (2)
O4A—C16A—C15A116.0 (2)O4B—C16B—C15B115.8 (2)
C17A—C16A—C15A119.2 (2)C17B—C16B—C15B118.9 (2)
C16A—C17A—C12A120.8 (2)C16B—C17B—C12B121.5 (2)
C16A—C17A—H17A119.6C16B—C17B—H17B119.2
C12A—C17A—H17A119.6C12B—C17B—H17B119.2
O1A—C18A—C19A107.7 (2)O1B—C18B—C19B110.5 (2)
O1A—C18A—H18A110.2O1B—C18B—H18C109.6
C19A—C18A—H18A110.2C19B—C18B—H18C109.6
O1A—C18A—H18B110.2O1B—C18B—H18D109.6
C19A—C18A—H18B110.2C19B—C18B—H18D109.6
H18A—C18A—H18B108.5H18C—C18B—H18D108.1
C18A—C19A—H19A109.5C18B—C19B—H19D109.5
C18A—C19A—H19B109.5C18B—C19B—H19E109.5
H19A—C19A—H19B109.5H19D—C19B—H19E109.5
C18A—C19A—H19C109.5C18B—C19B—H19F109.5
H19A—C19A—H19C109.5H19D—C19B—H19F109.5
H19B—C19A—H19C109.5H19E—C19B—H19F109.5
O2A—C20A—H20A109.5O2B—C20B—H20D109.5
O2A—C20A—H20B109.5O2B—C20B—H20E109.5
H20A—C20A—H20B109.5H20D—C20B—H20E109.5
O2A—C20A—H20C109.5O2B—C20B—H20F109.5
H20A—C20A—H20C109.5H20D—C20B—H20F109.5
H20B—C20A—H20C109.5H20E—C20B—H20F109.5
O3A—C21A—H21A109.5O3B—C21B—H21D109.5
O3A—C21A—H21B109.5O3B—C21B—H21E109.5
H21A—C21A—H21B109.5H21D—C21B—H21E109.5
O3A—C21A—H21C109.5O3B—C21B—H21F109.5
H21A—C21A—H21C109.5H21D—C21B—H21F109.5
H21B—C21A—H21C109.5H21E—C21B—H21F109.5
O4A—C22A—H22A109.5O4B—C22B—H22D109.5
O4A—C22A—H22B109.5O4B—C22B—H22E109.5
H22A—C22A—H22B109.5H22D—C22B—H22E109.5
O4A—C22A—H22C109.5O4B—C22B—H22F109.5
H22A—C22A—H22C109.5H22D—C22B—H22F109.5
H22B—C22A—H22C109.5H22E—C22B—H22F109.5
N2A—C23A—C10A176.9 (3)N2B—C23B—C10B177.5 (3)
C6A—C1A—C2A—C3A0.1 (4)C6B—C1B—C2B—C3B0.0 (4)
C1A—C2A—C3A—C4A0.7 (4)C1B—C2B—C3B—C4B0.4 (4)
C1A—C2A—C3A—Br1A179.6 (2)C1B—C2B—C3B—Br1B179.6 (2)
C2A—C3A—C4A—C5A0.7 (4)C2B—C3B—C4B—C5B0.5 (5)
Br1A—C3A—C4A—C5A179.6 (2)Br1B—C3B—C4B—C5B179.5 (2)
C3A—C4A—C5A—C6A0.1 (4)C3B—C4B—C5B—C6B1.8 (5)
C2A—C1A—C6A—C5A0.7 (4)C2B—C1B—C6B—C5B1.3 (4)
C2A—C1A—C6A—C7A180.0 (2)C2B—C1B—C6B—C7B176.5 (3)
C4A—C5A—C6A—C1A0.6 (4)C4B—C5B—C6B—C1B2.2 (4)
C4A—C5A—C6A—C7A180.0 (2)C4B—C5B—C6B—C7B175.6 (3)
C11A—N1A—C7A—C8A0.6 (4)C11B—N1B—C7B—C8B3.5 (4)
C11A—N1A—C7A—C6A178.3 (2)C11B—N1B—C7B—C6B177.2 (2)
C1A—C6A—C7A—N1A10.6 (4)C1B—C6B—C7B—N1B27.5 (4)
C5A—C6A—C7A—N1A170.1 (2)C5B—C6B—C7B—N1B150.2 (3)
C1A—C6A—C7A—C8A168.3 (2)C1B—C6B—C7B—C8B151.9 (3)
C5A—C6A—C7A—C8A11.0 (4)C5B—C6B—C7B—C8B30.4 (4)
N1A—C7A—C8A—C9A1.8 (4)N1B—C7B—C8B—C9B0.1 (4)
C6A—C7A—C8A—C9A177.1 (2)C6B—C7B—C8B—C9B179.2 (2)
C7A—C8A—C9A—C10A2.4 (4)C7B—C8B—C9B—C10B3.1 (4)
C7A—C8A—C9A—C12A175.0 (2)C7B—C8B—C9B—C12B177.3 (2)
C8A—C9A—C10A—C11A1.8 (4)C8B—C9B—C10B—C11B2.6 (4)
C12A—C9A—C10A—C11A175.5 (2)C12B—C9B—C10B—C11B177.8 (2)
C8A—C9A—C10A—C23A177.0 (3)C8B—C9B—C10B—C23B173.4 (3)
C12A—C9A—C10A—C23A5.7 (4)C12B—C9B—C10B—C23B6.2 (4)
C7A—N1A—C11A—O1A179.6 (2)C7B—N1B—C11B—O1B175.4 (2)
C7A—N1A—C11A—C10A0.1 (4)C7B—N1B—C11B—C10B4.0 (4)
C18A—O1A—C11A—N1A1.7 (3)C18B—O1B—C11B—N1B1.4 (4)
C18A—O1A—C11A—C10A178.6 (2)C18B—O1B—C11B—C10B178.0 (2)
C9A—C10A—C11A—N1A0.7 (4)C9B—C10B—C11B—N1B1.0 (4)
C23A—C10A—C11A—N1A178.1 (3)C23B—C10B—C11B—N1B177.1 (2)
C9A—C10A—C11A—O1A179.0 (2)C9B—C10B—C11B—O1B178.5 (2)
C23A—C10A—C11A—O1A2.2 (4)C23B—C10B—C11B—O1B2.4 (4)
C10A—C9A—C12A—C13A61.4 (4)C8B—C9B—C12B—C13B114.5 (3)
C8A—C9A—C12A—C13A115.8 (3)C10B—C9B—C12B—C13B66.0 (4)
C10A—C9A—C12A—C17A117.6 (3)C8B—C9B—C12B—C17B64.1 (4)
C8A—C9A—C12A—C17A65.2 (4)C10B—C9B—C12B—C17B115.5 (3)
C20A—O2A—C13A—C12A171.4 (3)C20B—O2B—C13B—C14B5.5 (4)
C20A—O2A—C13A—C14A11.6 (4)C20B—O2B—C13B—C12B173.9 (2)
C17A—C12A—C13A—O2A176.7 (2)C17B—C12B—C13B—O2B176.9 (2)
C9A—C12A—C13A—O2A4.2 (4)C9B—C12B—C13B—O2B1.6 (4)
C17A—C12A—C13A—C14A0.3 (4)C17B—C12B—C13B—C14B2.5 (4)
C9A—C12A—C13A—C14A178.7 (2)C9B—C12B—C13B—C14B179.0 (3)
O2A—C13A—C14A—C15A177.5 (2)O2B—C13B—C14B—C15B179.6 (2)
C12A—C13A—C14A—C15A0.7 (4)C12B—C13B—C14B—C15B0.3 (4)
C21A—O3A—C15A—C14A0.2 (4)C21B—O3B—C15B—C14B3.8 (4)
C21A—O3A—C15A—C16A180.0 (2)C21B—O3B—C15B—C16B175.5 (2)
C13A—C14A—C15A—O3A179.9 (2)C13B—C14B—C15B—O3B178.7 (2)
C13A—C14A—C15A—C16A0.3 (4)C13B—C14B—C15B—C16B2.1 (4)
C22A—O4A—C16A—C17A8.1 (4)C22B—O4B—C16B—C17B7.7 (4)
C22A—O4A—C16A—C15A172.8 (2)C22B—O4B—C16B—C15B173.3 (2)
O3A—C15A—C16A—O4A2.1 (4)O3B—C15B—C16B—O4B0.6 (3)
C14A—C15A—C16A—O4A178.0 (2)C14B—C15B—C16B—O4B179.9 (2)
O3A—C15A—C16A—C17A178.7 (2)O3B—C15B—C16B—C17B179.6 (2)
C14A—C15A—C16A—C17A1.1 (4)C14B—C15B—C16B—C17B1.1 (4)
O4A—C16A—C17A—C12A176.9 (2)O4B—C16B—C17B—C12B177.2 (2)
C15A—C16A—C17A—C12A2.1 (4)C15B—C16B—C17B—C12B1.7 (4)
C13A—C12A—C17A—C16A1.8 (4)C13B—C12B—C17B—C16B3.5 (4)
C9A—C12A—C17A—C16A177.3 (2)C9B—C12B—C17B—C16B177.9 (2)
C11A—O1A—C18A—C19A174.0 (2)C11B—O1B—C18B—C19B92.8 (3)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of C7A–C11A/N1A and C12A–C17A rings, respectively.
D—H···AD—HH···AD···AD—H···A
C1A—H1AA···N1A0.932.432.770 (3)102
C18B—H18C···N1B0.972.382.741 (4)101
C22A—H22C···Cg2i0.962.743.585 (3)147
C22B—H22E···Cg1ii0.962.683.511 (3)145
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC23H21BrN2O4
Mr469.32
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)7.9631 (2), 11.0499 (3), 23.9690 (6)
α, β, γ (°)92.201 (1), 91.968 (1), 99.586 (1)
V3)2076.31 (9)
Z4
Radiation typeMo Kα
µ (mm1)2.01
Crystal size (mm)0.59 × 0.10 × 0.05
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.384, 0.899
No. of measured, independent and
observed [I > 2σ(I)] reflections
31800, 9488, 7074
Rint0.043
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.098, 1.07
No. of reflections9488
No. of parameters549
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.79, 0.38

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of C7A–C11A/N1A and C12A–C17A rings, respectively.
D—H···AD—HH···AD···AD—H···A
C1A—H1AA···N1A0.932.432.770 (3)102
C18B—H18C···N1B0.972.382.741 (4)101
C22A—H22C···Cg2i0.962.743.585 (3)147
C22B—H22E···Cg1ii0.962.683.511 (3)145
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1, z+1.
 

Footnotes

This paper is dedicated to His Majesty King Bhumibol Adulyadej of Thailand (King Rama IX) for his sustainable development of the country.

Thomson Reuters ResearcherID: A-5085-2009.

§Additional correspondence author, email: hkfun@usm.my. Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The authors thank the Thailand Research Fund (TRF) for a research grant (RSA 5280033) and the Koshinocorporation Group (Japan), the Prince of Songkla University and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. AMI is grateful to the Director, NITK-Surathkal, India for providing research facilities and the Head of the Department of Chemistry and Dean R&D, NITK Surathkal, for their encouragement.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
First citationBorgna, P., Pregnolato, M., Gamba, I. A. & Mellerio, G. (1993). J. Heterocyclic Chem, 30, 1079–1084.  CrossRef CAS Google Scholar
First citationBruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationChantrapromma, S., Fun, H.-K., Suwunwong, T., Padaki, M. & Isloor, A. M. (2009). Acta Cryst. E65, o2914–o2915.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationChantrapromma, S., Fun, H.-K., Suwunwong, T., Padaki, M. & Isloor, A. M. (2010). Acta Cryst. E66, o79–o80.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationCosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationGoda, F. E., Abdel-Aziz, A. A.-M. & Attef, O. A. (2004). Bioorg. Med. Chem. 12, 1845–1852.  Web of Science CrossRef PubMed CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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Volume 66| Part 3| March 2010| Pages o641-o642
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