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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

(1E,4E)-1,5-Bis(2,4-di­methyl­phen­yl)penta-1,4-dien-3-one

aSchool of Life Science, Anhui Agricultural University, 130 West Yangtze Road, Hefei, Anhui Province 230036, People's Republic of China, and bShenzhen Wanxin Pharmatech Co Ltd, 1-108 Bioincubator building, 1st Gaoxin Road, Shenzhen, Guangdong 518057, People's Republic of China
*Correspondence e-mail: linyi0303@126.com

(Received 14 August 2009; accepted 23 August 2009; online 29 August 2009)

In the title compound, C21H22O, a derivative of the biologically active compound curcumin, the dihedral angle between the aromatic ring planes is 20.57 (11)°.

Related literature

For backgound to cucucmin and its biological properties, see: Began et al. (1999[Began, G., Sudharshan, E., Sankar, K. U. & Appu, R. G. (1999). J. Agric. Food Chem. 47, 4992-4997.]); Gautam et al. (2007[Gautam, S. C., Gao, X. & Dulchavsky, S. (2007). Adv. Exp. Med. Biol. 595, 321-41.]); Liang et al. (2008[Liang, G., Li, X. K., Chen, L., Yang, S. L., Wu, X. P., Studer, E., Gurley, E. C., Hylemon, P. B., Ye, F. Q., Li, Y. R. & Zhou, H. P. (2008). Bioorg. Med. Chem. Lett. 18, 1525-1529.]); Liang, Shao et al. (2009[Liang, G., Shao, L. L., Wang, Y., Zhao, C. G., Chu, Y. H., Xiao, J., Zhao, Y., Li, X. K. & Yang, S. L. (2009). Bioorg. Med. Chem. 17, 2623-2631.]); Liang, Tian et al. (2007[Liang, G., Tian, J.-L., Zhao, C.-G. & Li, X.-K. (2007). Acta Cryst. E63, o3630.]); Liang, Yang et al. (2007[Liang, G., Yang, S.-L., Wang, X.-H., Li, Y.-R. & Li, X.-K. (2007). Acta Cryst. E63, o4118.]); Liang, Zhou et al. (2009[Liang, G., Zhou, H. P., Wang, Y., Gurley, E. C., Feng, B., Chen, L., Xiao, J., Yang, S. L. & Li, X. K. (2009). J. Cell. Mol. Med. In the press.]); Maheshwari et al. (2006[Maheshwari, R. K., Singh, A. K., Gaddipati, J. & Srimal, R. C. (2006). Life Sci. 78, 2081-2087.]); Zhao et al. (2009[Zhao, C. G., Yang, J., Huang, Y., Liang, G. & Li, X. K. (2009). Z. Kristallogr. New Cryst. Struct. 224, 337-338.]).

[Scheme 1]

Experimental

Crystal data
  • C21H22O

  • Mr = 290.39

  • Monoclinic, P 21 /c

  • a = 4.9548 (7) Å

  • b = 26.555 (4) Å

  • c = 12.9632 (19) Å

  • β = 94.090 (3)°

  • V = 1701.3 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 293 K

  • 0.42 × 0.37 × 0.26 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.769, Tmax = 1.000

  • 8842 measured reflections

  • 3128 independent reflections

  • 2007 reflections with I > 2σ(I)

  • Rint = 0.095

Refinement
  • R[F2 > 2σ(F2)] = 0.065

  • wR(F2) = 0.173

  • S = 0.97

  • 3128 reflections

  • 203 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.21 e Å−3

Data collection: SMART (Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The title compound, C21H22O, (1E,4E)-1,5-bis(2,4-dimethylphenyl)penta-1,4-dien-3-one (I), is a mono-carbonyl analogue of curcumin. Curcumin has been found to possess a variety of pharmaceutical applications, for example, inhibiting the mutations and the formation of tumors, antioxidation, anti-inflammation and anti-virus (Began et al., 1999; Maheshwari et al., 2006; Gautam et al., 2007). According to the structural disadvantages of curcumin which is considered to be responsible for its weak pharmacokinetic profiles, a series of mono-carbonyl analogues have been designed and synthesized, and their biological activity in vitro and in vivo were evaluated.

Derivatives of dibenzylidene acetone, cyclopentanone and cyclohexanone exhibit potent anti-inflammatory, antibacterial and anti-cancer activity.(Liang et al., 2008; Liang et al., 2008; Liang, Shao et al., 2009; Liang, Zhou et al., 2009). This fact leads to the significance of these synthetic mono-carbonyl analogues of curcumin. Several of these derivatives have been reported their crystal structures (Liang, Tian et al., 2007; Liang, Yang et al., 2007; Zhao et al., 2009). In the present paper, we describe the crystal structure of the title compound C21H22O (I) here. Its geometrical parameters of are normal, the dihedral angle between the six-membered aromatic ring planes is 20.57 (11)°.

Related literature top

For backgound to cucucmin and its biological properties, see: Began et al. (1999); Gautam et al. (2007); Liang et al. (2008); Liang, Shao et al. (2009); Liang, Tian et al. (2007); Liang, Yang et al.(2007); Liang, Zhou et al. (2009); Maheshwari et al. (2006); Zhao et al. (2009).

Experimental top

To a solution of 15 mmol 2,4-dimethylbenzaldehyde in MeOH (10 ml) was added 7.5 mmol acetone. The solution was stirred at room temperature for 20 min, followed by added dropwise 20% (w/v) NaOH (1.5 ml, 7.5 mmol). The mixture was stirred at RT and monitored with TLC. When the reaction finished, the residue was poured into saturated NH4Cl solution and filtered. The precipitate was washed and purified by chromatography over silica gel using CH2Cl2 / CH3OH as the eluent to afford the pure product (yield: 38.2%). Colourless blokcs of (I) were grown in a CH2Cl2—CH3OH mixture (6:2 v/v) by slow evaporation (mp 436–437 K). 1H-NMR (CDCl3): 2.34 (s, 6H, Ar4—CH3), 2.44 (s, 6H, Ar2—CH3), 6.96 (d, 2H, J=16.0 Hz, =CH—C=O), 7.05 (m, 4H, Ar—H3,5), 7.56 (d, 2H, J=8.0 Hz, Ar—H6), 8.0 (d, 2H, J=16.0 Hz, Ar—CH=C). ESI-MS m/z: 603.8 (2M+Na)+, calcd for C21H22O: 290.4.

Refinement top

The H atoms were positioned geometrically (C—H = 0.93–0.97 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C).

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) shoiwng 50% displacement ellipsoids for the non-hydrogen atoms.
(1E,4E)-1,5-Bis(2,4-dimethylphenyl)penta-1,4-dien-3-one top
Crystal data top
C21H22OF(000) = 624
Mr = 290.39Dx = 1.134 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1845 reflections
a = 4.9548 (7) Åθ = 4.4–44.1°
b = 26.555 (4) ŵ = 0.07 mm1
c = 12.9632 (19) ÅT = 293 K
β = 94.090 (3)°Prism, green
V = 1701.3 (4) Å30.42 × 0.37 × 0.26 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer
3128 independent reflections
Radiation source: fine-focus sealed tube2007 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.095
ω scansθmax = 25.5°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
h = 56
Tmin = 0.769, Tmax = 1.000k = 3132
8842 measured reflectionsl = 715
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)] = 0.065Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.173H-atom parameters constrained
S = 0.97 w = 1/[σ2(Fo2) + (0.0858P)2]
where P = (Fo2 + 2Fc2)/3
3128 reflections(Δ/σ)max = 0.057
203 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C21H22OV = 1701.3 (4) Å3
Mr = 290.39Z = 4
Monoclinic, P21/cMo Kα radiation
a = 4.9548 (7) ŵ = 0.07 mm1
b = 26.555 (4) ÅT = 293 K
c = 12.9632 (19) Å0.42 × 0.37 × 0.26 mm
β = 94.090 (3)°
Data collection top
Bruker SMART CCD
diffractometer
3128 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
2007 reflections with I > 2σ(I)
Tmin = 0.769, Tmax = 1.000Rint = 0.095
8842 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0650 restraints
wR(F2) = 0.173H-atom parameters constrained
S = 0.97Δρmax = 0.21 e Å3
3128 reflectionsΔρmin = 0.21 e Å3
203 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
O11.4353 (4)0.35616 (7)0.08357 (12)0.0700 (5)
C11.2047 (5)0.36963 (8)0.09662 (16)0.0510 (6)
C21.0758 (5)0.35782 (8)0.19171 (16)0.0528 (6)
H20.90310.37030.19940.063*
C31.1920 (4)0.33037 (8)0.26714 (16)0.0479 (6)
H31.36210.31730.25660.057*
C41.0435 (5)0.39838 (8)0.01739 (16)0.0545 (6)
H40.86980.40830.03130.065*
C51.1329 (5)0.41070 (8)0.07216 (16)0.0516 (6)
H51.30190.39820.08600.062*
C60.9942 (4)0.44212 (7)0.15263 (16)0.0473 (6)
C71.0565 (4)0.43873 (7)0.25633 (16)0.0493 (6)
C80.9237 (5)0.47084 (8)0.32771 (17)0.0557 (6)
H80.96330.46840.39660.067*
C90.7367 (5)0.50614 (8)0.30192 (18)0.0570 (6)
C100.6759 (5)0.50852 (9)0.19985 (19)0.0645 (7)
H100.54820.53160.18010.077*
C110.8023 (5)0.47709 (9)0.12683 (18)0.0603 (6)
H110.75770.47940.05850.072*
C121.0812 (4)0.31833 (7)0.36552 (15)0.0455 (5)
C130.8956 (5)0.34978 (8)0.40688 (17)0.0564 (6)
H130.84290.37890.37100.068*
C140.7855 (5)0.33986 (9)0.49876 (18)0.0614 (7)
H140.66070.36200.52390.074*
C150.8597 (5)0.29692 (9)0.55428 (16)0.0544 (6)
C161.0474 (4)0.26532 (9)0.51378 (16)0.0535 (6)
H161.09980.23650.55060.064*
C171.1613 (4)0.27453 (8)0.42090 (15)0.0466 (5)
C181.2581 (5)0.40116 (8)0.29188 (17)0.0626 (7)
H18A1.25950.40250.36580.094*
H18B1.20810.36790.27120.094*
H18C1.43500.40910.26130.094*
C190.5986 (6)0.54084 (9)0.3819 (2)0.0795 (8)
H19A0.68630.53830.44530.119*
H19B0.60980.57490.35720.119*
H19C0.41200.53130.39380.119*
C201.3587 (5)0.23772 (9)0.38199 (18)0.0640 (7)
H20A1.38900.21100.43130.096*
H20B1.52670.25450.37250.096*
H20C1.28710.22400.31720.096*
C210.7377 (5)0.28438 (12)0.65406 (18)0.0784 (8)
H21A0.63610.31270.67610.118*
H21B0.87920.27650.70600.118*
H21C0.61980.25590.64380.118*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0565 (11)0.0924 (13)0.0619 (11)0.0062 (9)0.0100 (9)0.0172 (9)
C10.0505 (14)0.0541 (13)0.0482 (13)0.0077 (11)0.0023 (11)0.0032 (10)
C20.0491 (13)0.0618 (14)0.0476 (13)0.0010 (11)0.0044 (11)0.0058 (11)
C30.0476 (13)0.0479 (12)0.0482 (13)0.0034 (10)0.0043 (10)0.0009 (10)
C40.0522 (14)0.0625 (14)0.0492 (13)0.0007 (11)0.0061 (11)0.0072 (11)
C50.0558 (14)0.0491 (13)0.0498 (13)0.0050 (10)0.0036 (11)0.0002 (10)
C60.0546 (14)0.0411 (11)0.0459 (13)0.0053 (10)0.0016 (10)0.0001 (9)
C70.0548 (13)0.0456 (12)0.0474 (13)0.0087 (10)0.0037 (11)0.0022 (10)
C80.0668 (16)0.0528 (13)0.0474 (13)0.0088 (12)0.0034 (11)0.0045 (11)
C90.0682 (16)0.0427 (12)0.0588 (15)0.0048 (12)0.0049 (12)0.0009 (11)
C100.0678 (17)0.0532 (14)0.0716 (17)0.0092 (12)0.0008 (13)0.0069 (13)
C110.0715 (17)0.0579 (14)0.0520 (14)0.0001 (12)0.0084 (12)0.0018 (11)
C120.0447 (12)0.0481 (12)0.0435 (12)0.0012 (10)0.0020 (10)0.0009 (10)
C130.0607 (15)0.0549 (13)0.0539 (14)0.0141 (11)0.0074 (12)0.0058 (11)
C140.0598 (15)0.0696 (16)0.0564 (15)0.0172 (13)0.0156 (12)0.0002 (12)
C150.0517 (14)0.0657 (15)0.0461 (13)0.0025 (12)0.0056 (11)0.0027 (11)
C160.0531 (14)0.0586 (14)0.0487 (13)0.0035 (11)0.0031 (11)0.0115 (11)
C170.0455 (12)0.0462 (12)0.0479 (13)0.0023 (10)0.0015 (10)0.0012 (10)
C180.0700 (16)0.0639 (15)0.0549 (14)0.0062 (13)0.0110 (12)0.0017 (12)
C190.095 (2)0.0616 (16)0.0795 (19)0.0047 (14)0.0140 (16)0.0103 (14)
C200.0720 (17)0.0580 (14)0.0632 (15)0.0108 (13)0.0140 (13)0.0003 (12)
C210.0716 (18)0.107 (2)0.0586 (16)0.0085 (16)0.0199 (13)0.0149 (15)
Geometric parameters (Å, º) top
O1—C11.221 (3)C12—C171.409 (3)
C1—C21.462 (3)C13—C141.370 (3)
C1—C41.469 (3)C13—H130.9300
C2—C31.319 (3)C14—C151.384 (3)
C2—H20.9300C14—H140.9300
C3—C121.459 (3)C15—C161.383 (3)
C3—H30.9300C15—C211.504 (3)
C4—C51.313 (3)C16—C171.388 (3)
C4—H40.9300C16—H160.9300
C5—C61.468 (3)C17—C201.496 (3)
C5—H50.9300C18—H18A0.9600
C6—C111.387 (3)C18—H18B0.9600
C6—C71.403 (3)C18—H18C0.9600
C7—C81.389 (3)C19—H19A0.9600
C7—C181.507 (3)C19—H19B0.9600
C8—C91.376 (3)C19—H19C0.9600
C8—H80.9300C20—H20A0.9600
C9—C101.379 (3)C20—H20B0.9600
C9—C191.513 (3)C20—H20C0.9600
C10—C111.379 (3)C21—H21A0.9601
C10—H100.9300C21—H21B0.9601
C11—H110.9300C21—H21C0.9601
C12—C131.379 (3)
O1—C1—C2121.6 (2)C12—C13—H13118.7
O1—C1—C4121.5 (2)C13—C14—C15120.2 (2)
C2—C1—C4116.9 (2)C13—C14—H14119.9
C3—C2—C1123.4 (2)C15—C14—H14119.9
C3—C2—H2118.3C14—C15—C16117.6 (2)
C1—C2—H2118.3C14—C15—C21121.4 (2)
C2—C3—C12126.7 (2)C16—C15—C21121.0 (2)
C2—C3—H3116.6C15—C16—C17123.3 (2)
C12—C3—H3116.7C15—C16—H16118.4
C5—C4—C1123.1 (2)C17—C16—H16118.4
C5—C4—H4118.4C16—C17—C12118.1 (2)
C1—C4—H4118.4C16—C17—C20119.59 (19)
C4—C5—C6126.8 (2)C12—C17—C20122.3 (2)
C4—C5—H5116.6C7—C18—H18A109.5
C6—C5—H5116.6C7—C18—H18B109.5
C11—C6—C7118.4 (2)H18A—C18—H18B109.5
C11—C6—C5120.2 (2)C7—C18—H18C109.5
C7—C6—C5121.4 (2)H18A—C18—H18C109.5
C8—C7—C6118.2 (2)H18B—C18—H18C109.5
C8—C7—C18119.7 (2)C9—C19—H19A109.5
C6—C7—C18122.09 (19)C9—C19—H19B109.5
C9—C8—C7123.5 (2)H19A—C19—H19B109.5
C9—C8—H8118.3C9—C19—H19C109.5
C7—C8—H8118.3H19A—C19—H19C109.5
C8—C9—C10117.5 (2)H19B—C19—H19C109.5
C8—C9—C19121.9 (2)C17—C20—H20A109.5
C10—C9—C19120.7 (2)C17—C20—H20B109.5
C11—C10—C9120.8 (2)H20A—C20—H20B109.5
C11—C10—H10119.6C17—C20—H20C109.5
C9—C10—H10119.6H20A—C20—H20C109.5
C10—C11—C6121.7 (2)H20B—C20—H20C109.5
C10—C11—H11119.2C15—C21—H21A109.5
C6—C11—H11119.1C15—C21—H21B109.5
C13—C12—C17118.2 (2)H21A—C21—H21B109.5
C13—C12—C3120.67 (19)C15—C21—H21C109.5
C17—C12—C3121.08 (19)H21A—C21—H21C109.5
C14—C13—C12122.6 (2)H21B—C21—H21C109.5
C14—C13—H13118.7
O1—C1—C2—C33.1 (3)C9—C10—C11—C60.1 (4)
C4—C1—C2—C3176.8 (2)C7—C6—C11—C100.8 (3)
C1—C2—C3—C12177.8 (2)C5—C6—C11—C10177.5 (2)
O1—C1—C4—C51.1 (4)C2—C3—C12—C1326.1 (3)
C2—C1—C4—C5178.8 (2)C2—C3—C12—C17154.2 (2)
C1—C4—C5—C6175.49 (19)C17—C12—C13—C140.5 (3)
C4—C5—C6—C1124.6 (3)C3—C12—C13—C14179.7 (2)
C4—C5—C6—C7157.2 (2)C12—C13—C14—C150.1 (4)
C11—C6—C7—C80.4 (3)C13—C14—C15—C160.4 (4)
C5—C6—C7—C8177.83 (18)C13—C14—C15—C21178.5 (2)
C11—C6—C7—C18178.7 (2)C14—C15—C16—C170.4 (3)
C5—C6—C7—C183.0 (3)C21—C15—C16—C17178.4 (2)
C6—C7—C8—C90.7 (3)C15—C16—C17—C120.1 (3)
C18—C7—C8—C9179.9 (2)C15—C16—C17—C20178.8 (2)
C7—C8—C9—C101.4 (3)C13—C12—C17—C160.4 (3)
C7—C8—C9—C19179.3 (2)C3—C12—C17—C16179.83 (19)
C8—C9—C10—C111.0 (4)C13—C12—C17—C20179.2 (2)
C19—C9—C10—C11179.7 (2)C3—C12—C17—C201.0 (3)

Experimental details

Crystal data
Chemical formulaC21H22O
Mr290.39
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)4.9548 (7), 26.555 (4), 12.9632 (19)
β (°) 94.090 (3)
V3)1701.3 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.42 × 0.37 × 0.26
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2002)
Tmin, Tmax0.769, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
8842, 3128, 2007
Rint0.095
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.065, 0.173, 0.97
No. of reflections3128
No. of parameters203
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.21

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

This work was supported by the Key Sci&Tech Project of Wenzhou Government (grant No. 2008S0629).

References

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