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ISSN: 2056-9890

Crystal structures of 3,5-bis­­[(E)-3-hy­dr­oxy­benzyl­­idene]-1-methyl­piperidin-4-one and 3,5-bis­­[(E)-2-chloro­benzyl­­idene]-1-methyl­piperidin-4-one

aLaboratory of Organic Synthesis, Department of Chemistry, Faculty of Mathematics and Natural Sciences, Riau University, Pekanbaru 26293, Indonesia, bDepartment of Chemistry, Faculty of Mathematics and Natural Sciences, Padjadjaran University, Jalan Raya Bandung-Sumedang Km 21, Jatinangor 45363, Sumedang, Indonesia, cDepartment of Chemistry, Faculty of Mathematics and Narural Sciences, Padjadjaran University, Jalan Raya Bandung-Sumedang Km 21, Jatinangor 45363, Sumedang, Indonesia, dX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and eDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
*Correspondence e-mail: mustaqim@usm.my

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 21 October 2015; accepted 5 November 2015; online 11 November 2015)

The title compounds, C20H19NO3, (1), and C20H17Cl2NO, (2), are the 3-hy­droxy­benzyl­idene and 2-chloro­benzyl­idene derivatives, respectively, of curcumin [systematic name: (1E,6E)-1,7-bis­(4-hy­droxy-3-meth­oxy­phen­yl)-1,6-hepta­diene-3,5-dione]. The dihedral angles between the benzene rings in each compound are 21.07 (6)° for (1) and 13.4 (3)° for (2). In both compounds, the piperidinone rings adopt a sofa confirmation and the methyl group attached to the N atom is in an equatorial position. In the crystal of (1), two pairs of O—H⋯N and O—H⋯O hydrogen bonds link the mol­ecules, forming chains along [10-1]. The chains are linked via C—H⋯O hydrogen bonds, forming undulating sheets parallel to the ac plane. In the crystal of (2), mol­ecules are linked by weak C—H⋯Cl hydrogen bonds, forming chains along the [204] direction. The chains are linked along the a-axis direction by ππ inter­actions [inter-centroid distance = 3.779 (4) Å]. For compound (2), the crystal studied was a non-merohedral twin with the refined ratio of the twin components being 0.116 (6):0.886 (6).

1. Chemical context

Curcumin (diferuloyl­methane) is a naturally occurring biologically active compound, isolated from the root of the tumeric plant (Curcuma longa) (Dandia et al., 2012[Dandia, A., Jain, A. K. & Sharma, S. (2012). Tetrahedron Lett. 53, 5859-5863.]). It has been shown to exhibit anti-oxidant (Rostom et al., 2009[Rostom, S. A. F., Hassan, G. S. & El-Subbagh, H. I. (2009). Arch. Pharm. Chem. Life Sci. 342, 584-590.]), anti-inflammatory (Suzuki et al., 2005[Suzuki, M., Nakamura, T., Iyoki, S., Fujiwara, A., Watanabe, Y., Mohri, K., Isobe, K., Ono, K. & Yano, S. (2005). Biol. Pharm. Bull. 28, 1438-1443.]), anti­viral (Kumar et al., 2007[Kumar, R. R., Perumal, S., Senthilkumar, P., Yogeeswari, P. & Sriram, D. (2007). Bioorg. Med. Chem. Lett. 17, 6459-6462.]) and anti­bacterial (Bandgar et al., 2012[Bandgar, B. P., Jalde, S. S., Korbad, B. L., Patil, S. A., Chavan, H. V., Kinkar, S. N., Adsul, L. K., Shringare, S. N. & Nile, S. H. (2012). J. Enzyme Inhib. Med. Chem. 27, 267-274.]) activities, and thus has potential against various malignant cancers, diabetes, allergies, arthritis and other chronic illnesses (Yadav et al., 2010[Yadav, B., Taurin, S., Rosengren, R. J., Schumacher, M., Diederich, M., Somers-Edgar, T. J. & Larsen, L. (2010). Bioorg. Med. Chem. 18, 6701-6707.]; Reddy et al., 2009[Reddy, B. V., Sundari, J. S., Balamurugan, E. & Menon, V. P. (2009). Mol. Cell. Biochem. 331, 127-133.]; Aggarwal et al., 2003[Aggarwal, B. B., Kumar, A. & Bharti, A. C. (2003). Anticancer Res. 23, 363-398.]; Insuasty et al., 2013[Insuasty, B., Becerra, D., Quiroga, J., Abonia, R., Nogueras, M. & Cobo, J. (2013). Eur. J. Med. Chem. 60, 1-9.]; Wu et al., 2013[Wu, J. Z., Zhang, Y. L., Cai, Y. P., Wang, J., Weng, B. X., Tang, Q. Q., Chen, X. J., Pan, Z., Liang, G. & Yang, S. L. (2013). Bioorg. Med. Chem. 21, 3058-3065.]). For the purpose of finding new deriv­atives with increased systemic bioavailability and enhanced pharmacological activity (Zhao et al., 2010[Zhao, C. G., Cai, Y. P., He, X. Z., Li, J. L., Zhang, L., Wu, J. Z., Zhao, Y. J., Yang, S. L., Li, X. K., Li, W. L. & Liang, G. A. (2010). Eur. J. Med. Chem. 45, 5773-5780.]), chemical modifications as well as the synthesis of curcumin analogues have been attempted by many research groups in order to find a better treatment for various diseases (Siddiqui et al., 2006[Siddiqui, A. M., Cui, X. X., Wu, R. Q., Dong, W. F., Zhou, M., Hu, M. W., Simms, H. H. & Wang, P. (2006). Crit. Care Med. 34, 1874-1882.]; Gregory et al., 2013[Gregory, M., Dandavati, A., Lee, M., Tzou, S., Savagian, M., Brien, K. A., Satam, V., Patil, P. & Lee, M. (2013). Med. Chem. Res. 22, 5588-5597.]). Analogous compounds to (E)-3,5-bis­(benzyl­idene)-4-piperidones present noteworthy cytotoxic activity against leukemia cell lines and colon cancer, among others (Gregory et al., 2013[Gregory, M., Dandavati, A., Lee, M., Tzou, S., Savagian, M., Brien, K. A., Satam, V., Patil, P. & Lee, M. (2013). Med. Chem. Res. 22, 5588-5597.]). Different substituents were designed to investigate and discuss the structure–activity relationship (Insuasty et al., 2013[Insuasty, B., Becerra, D., Quiroga, J., Abonia, R., Nogueras, M. & Cobo, J. (2013). Eur. J. Med. Chem. 60, 1-9.]). Herein, we report on the synthesis, characterization and crystal structures of two mono-carbonyl analogues of curcumin, namely N-methyl-(3E,5E)-3,5-bis­(3-hy­droxy­benzyl­idene)-4-piperidone (1) and N-methyl-(3E,5E)-3,5-bis­(2-chloro­benzyl­idene)-4-piperidone (2).

[Scheme 1]
[Scheme 2]

2. Structural commentary

The mol­ecular structures of compounds (1) and (2) are shown in Figs. 1[link] and 2[link], respectively. Compound (1) crystallized in the triclinic space group P[\overline{1}] (Z = 2), while compound (2) crystallized in the monoclinic space group P21/n (Z = 4).

[Figure 1]
Figure 1
The mol­ecular structure of compound (1), showing 50% probability displacement ellipsoids and the atom labelling.
[Figure 2]
Figure 2
The mol­ecular structure of compound (2), showing 50% probability displacement ellipsoids and the atom labelling.

The benzene rings (C1–C6 and C14–C19) are inclined to one another by 21.07 (6)° in (1) and by 13.4 (3)° in (2). Both compounds exhibit E conformations about the C7=C8 and C13=C10 bonds. In both compounds, the piperidinone ring (N1/C8–C12) adopts a sofa conformation with atom N1 displaced from the mean plane through the five C atoms (C8–C12) by 0.7052 (10) Å in (1) and 0.705 (5) Å in (2). The puckering parameters for the piperidinone ring conformation in (1) are Q = 0.5280 (12) Å, θ = 55.17 (14)° and φ = 353.08 (17)°, while for (2) they are Q = 0.526 (6) Å, θ = 126.1 (7)° and φ = 182.8 (8)°. In both compounds the methyl group attached to atom N1 is in an equatorial position on the piperidinone ring.

3. Supra­molecular features

In the crystal of compound (1), mol­ecules are linked via pairs of O—H⋯N hydrogen bonds, forming inversion dimers enclosing an R22(18) ring motif (Table 1[link] and Fig. 3[link]). These dimers are linked by pairs of O—H⋯O hydrogen bonds, enclosing an R22(18) ring motif, forming chains along [10[\overline{1}]] (Table 1[link] and Fig. 4[link]). The chains are linked via pairs of C—H⋯O hydrogen bonds (Table 1[link] and Fig. 4[link]), forming undulating sheets lying parallel to the ac plane (Fig. 5[link]).

Table 1
Hydrogen-bond geometry (Å, °) for (1)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O1⋯N1i 0.96 (2) 1.81 (2) 2.7278 (14) 160 (2)
O3—H1O3⋯O2ii 0.88 (2) 1.87 (2) 2.7359 (15) 171 (2)
C17—H17A⋯O3iii 0.95 2.51 3.4032 (16) 157
Symmetry codes: (i) -x+2, -y, -z; (ii) -x+1, -y, -z+1; (iii) -x+1, -y+1, -z+2.
[Figure 3]
Figure 3
An inversion dimer found in compound (1), formed by O—H⋯N hydrogen bonds (dashed lines; see Table 1[link]).
[Figure 4]
Figure 4
Inversion dimers found in compound (1), formed by O—H⋯O and C—H⋯N hydrogen bonds (dashed lines; see Table 1[link]).
[Figure 5]
Figure 5
The crystal packing of compound (1), viewed along the a axis. Dashed lines indicate hydrogen bonds (see Table 1[link]). H atoms not involved in the hydrogen bonding have been omitted for clarity.

In the crystal of compound (2), mol­ecules are linked by a weak C4—H4A⋯Cl2i hydrogen bond, forming zigzag chains along [204] (Table 2[link] and Fig. 6[link]). The chains are linked along the a-axis direction by ππ inter­actions [Cg2⋯Cg3i = 3.779 (4) Å, where Cg2 and Cg3 are the centroids of rings C1–C6 and C14–C19, respectively; symmetry code: (i) − x + 1, −y, −z].

Table 2
Hydrogen-bond geometry (Å, °) for (2)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
C4—H4A⋯Cl2i 0.95 2.85 3.587 (7) 135
Symmetry code: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].
[Figure 6]
Figure 6
A view along the a axis of the crystal packing of compound (2), showing a zigzag chain formed by weak C—H⋯Cl hydrogen bonds (dashed lines; see Table 2[link]). H atoms not involved in the hydrogen bonding have been omitted for clarity.

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.36, last update February 2015; Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. 53, 662-671.]) of substructure (3E,5E)-3,5-di­benzyl­idene-1-methyl­piperidin-4-one gave 49 hits. One compound, 3,5-bis­(4-chloro­benzyl­idene)-1-methyl­piperidin-4-one, is the 4-chloro­benzyl­idene isomer of compound (2) (UNOXOL; Nesterov et al., 2011[Nesterov, V. V., Sarkisov, S. S., Shulaev, V. & Nesterov, V. N. (2011). Acta Cryst. E67, o760-o761.]). Here, the benzene rings are inclined to one another by 7.58 (8)°, compared to 21.07 (6)° in (1) and 13.4 (3)° in (2). The piperidinone ring also adopts a sofa conformation with the N atom displaced from the mean plane of the five C atoms by 0.7714 (15) Å, compared to 0.7052 (10) Å in (1) and 0.705 (5) Å in (2).

5. Synthesis and crystallization

Both compounds were synthesized according to a partially modified procedure of a previous report (Gregory et al., 2013[Gregory, M., Dandavati, A., Lee, M., Tzou, S., Savagian, M., Brien, K. A., Satam, V., Patil, P. & Lee, M. (2013). Med. Chem. Res. 22, 5588-5597.]).

Compound (1): The corresponding N-methyl-4-piperidone (0.99 g, 0.01 mol), 3-hy­droxy­benzaldehyde (2.23 g, 0.02 mol), 40% aq. NaOH (0.7 ml) and 95% EtOH (5 ml) were mixed with stirring at room temperature for 30 min. The reaction mixture was subjected to microwave irradiation for 3 min at a power of 180 W and temperature of 333 K. The reaction product was cooled and cold water was added. The precipitate formed was filtered and recrystallized from a mixture of n-hexa­ne–ethyl acetate to afford dark yellowish crystals of compound (1) (yield: 3.4 g, 34.5%; m.p. 409–410 K). Rf = 0.43 (n-hexa­ne:EtOAc = 1:1). UV (MeOH) λmax: 364 nm ( 4,600). IR (KBr) νmax cm−1: 3400, 1658, 1600 and 1504 cm−1. 1H NMR (500 MHz, CDCl3): δ (p.p.m.) 8.04 (2H, s), 7.31 (2H, d, J = 7.5 Hz), 7.26 (2H, t, J = 7.5 Hz), 6.99 (2H, d, J = 8.0 Hz), 6.93 (2H, t, J = 7.5 Hz), 3.72 (4H, s) and 2.41 (3H, s). 13C NMR (125 MHz, CDCl3): δ (p.p.m.) 185.9, 156.6, 133.2, 130.7, 130.5, 130.3, 122.6, 119.4, 115.7, 57.2, 45.2. HR–ESI–TOFMS: calculated for C20H19NO3 [M + H]+, m/z 321.1365, found m/z 322.1434.

Compound (2): The corresponding N-methyl-4-piperidone (0.98 g, 0.01 mol), 2-chloro­benzaldehyde (2.20 g, 0.02 mol), 40% aq. NaOH (0.7 ml) and 95% EtOH (5 ml) was stirred at room temperature for 30 min. The reaction mixture was subjected to microwave irradiation for 3 min at a power of 180 W and temperature of 333 K. The reaction product was cooled and cold water was added. The precipitate formed was filtered and recrystallized from a mixture of n-hexa­ne–ethyl acetate to afford yellowish crystals of compound (2) (yield: 3.8 g, 38.4%; m.p. 408–410 K). Rf = 0.60 (CH2Cl2:MeOH = 9.5:0.5). UV (MeOH) λmax: 309 nm ( 4,400). IR (KBr) νmax cm−1: 3328, 1640 cm−1. 1H NMR (500 MHz, CDCl3): δ (p.p.m.) 8.00 (2H, s), 7.46 (2H, dd, J = 8.0, 1.5 Hz), 7.31 (2H, dd, J = 8.0, 1.5 Hz), 7.30 (2H, d, J = 7.5 Hz), 7.24 (2H, dd, J = 7.5, 1.5 Hz), 3.61 (4H, s), 2.37 (3H, s). 13C NMR (125 MHz, CDCl3): δ (p.p.m.) 186.1, 135.2, 134.3, 134.0, 133.6, 130.3, 130.0, 129.9, 126.4, 56.7, 45.5. HR–ESI–TOFMS: calculated for C20H17Cl2NO [M + H]+, m/z 357.0687, found m/z 358.0776.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3[link]. The O-bound H atoms were located in difference Fourier maps and freely refined. The remaining H atoms were positioned geometrically and refined using a riding model: C—H = 0.95–0.99 Å with Uiso(H) = 1.5Ueq(C-meth­yl) and 1.2Ueq(C) for other H atoms. A rotating group model was applied to the methyl groups. For compound (2) the crystal studied was a non-merohedral twin with a ratio of the twin components of 0.116 (6):0.886 (6).

Table 3
Experimental details

  (1) (2)
Crystal data
Chemical formula C20H19NO3 C20H17Cl2NO
Mr 321.36 358.24
Crystal system, space group Triclinic, P[\overline{1}] Monoclinic, P21/n
Temperature (K) 100 100
a, b, c (Å) 7.4852 (6), 9.8588 (9), 11.6115 (10) 7.540 (3), 10.623 (4), 21.119 (7)
α, β, γ (°) 111.7924 (17), 96.7983 (18), 92.8848 (17) 90, 98.671 (5), 90
V3) 785.90 (12) 1672.2 (10)
Z 2 4
Radiation type Mo Kα Mo Kα
μ (mm−1) 0.09 0.39
Crystal size (mm) 0.29 × 0.24 × 0.11 0.32 × 0.08 × 0.08
 
Data collection
Diffractometer Bruker APEX DUO CCD area detector Bruker APEX DUO CCD area detector
Absorption correction Multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
No. of measured, independent and observed [I > 2σ(I)] reflections 10462, 3562, 3133 3105, 3105, 2591
Rint 0.021 0.084
(sin θ/λ)max−1) 0.650 0.606
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.117, 1.04 0.077, 0.192, 1.18
No. of reflections 3562 3105
No. of parameters 226 218
H-atom treatment H atoms treated by a mixture of independent and constrained refinement H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.37, −0.21 0.45, −0.43
Computer programs: APEX2 and SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

For both compounds, data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

(1) 3,5-Bis[(E)-3-hydroxybenzylidene]-1-methylpiperidin-4-one top
Crystal data top
C20H19NO3Z = 2
Mr = 321.36F(000) = 340
Triclinic, P1Dx = 1.358 Mg m3
a = 7.4852 (6) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.8588 (9) ÅCell parameters from 3138 reflections
c = 11.6115 (10) Åθ = 2.8–32.1°
α = 111.7924 (17)°µ = 0.09 mm1
β = 96.7983 (18)°T = 100 K
γ = 92.8848 (17)°Block, orange
V = 785.90 (12) Å30.29 × 0.24 × 0.11 mm
Data collection top
Bruker APEX DUO CCD area-detector
diffractometer
3133 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.021
φ and ω scansθmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 99
k = 1212
10462 measured reflectionsl = 1515
3562 independent reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.039H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.117 w = 1/[σ2(Fo2) + (0.0694P)2 + 0.2741P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
3562 reflectionsΔρmax = 0.37 e Å3
226 parametersΔρmin = 0.21 e Å3
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 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O11.16705 (13)0.33469 (10)0.27862 (8)0.0217 (2)
O20.78550 (12)0.06971 (10)0.30379 (9)0.0219 (2)
O30.36575 (12)0.35383 (10)0.81746 (9)0.0197 (2)
N11.15110 (13)0.28041 (10)0.38630 (9)0.0139 (2)
C11.36371 (16)0.10777 (13)0.09923 (11)0.0159 (2)
H1A1.41170.05500.18490.019*
C21.47889 (17)0.16263 (13)0.01131 (12)0.0182 (3)
H2A1.60590.14780.03760.022*
C31.41151 (17)0.23866 (13)0.11397 (12)0.0184 (3)
H3A1.49220.27700.17280.022*
C41.22557 (17)0.25933 (13)0.15432 (11)0.0159 (3)
C51.10880 (16)0.20577 (12)0.06675 (11)0.0145 (2)
H5A0.98190.22020.09360.017*
C61.17643 (16)0.13047 (12)0.06113 (11)0.0137 (2)
C71.04624 (16)0.09053 (12)0.14976 (11)0.0141 (2)
H7A0.93480.15140.12380.017*
C81.06141 (16)0.02010 (12)0.26281 (11)0.0136 (2)
C90.91333 (16)0.02744 (13)0.33844 (11)0.0152 (2)
C100.92406 (16)0.15518 (12)0.45975 (11)0.0139 (2)
C111.08023 (16)0.27250 (12)0.49664 (11)0.0144 (2)
H11A1.04010.36870.54540.017*
H11B1.17790.25150.55110.017*
C121.21650 (16)0.13979 (12)0.31593 (11)0.0148 (2)
H12A1.30700.11440.37210.018*
H12B1.27600.14840.24680.018*
C130.78975 (16)0.15721 (12)0.52792 (11)0.0145 (2)
H13A0.70020.07550.49140.017*
C140.75909 (16)0.26419 (12)0.64853 (11)0.0136 (2)
C150.58209 (16)0.25978 (12)0.67642 (11)0.0143 (2)
H15A0.49130.18880.61790.017*
C160.53717 (16)0.35752 (12)0.78829 (11)0.0150 (2)
C170.66948 (17)0.46108 (13)0.87504 (11)0.0173 (3)
H17A0.63960.52960.95090.021*
C180.84563 (17)0.46288 (13)0.84920 (11)0.0165 (3)
H18A0.93660.53200.90930.020*
C190.89262 (16)0.36657 (13)0.73795 (11)0.0154 (2)
H19A1.01420.36990.72240.018*
C201.29894 (17)0.39929 (13)0.42690 (12)0.0183 (3)
H20A1.25740.49070.48140.027*
H20B1.33640.41230.35330.027*
H20C1.40170.37420.47310.027*
H1O11.044 (3)0.321 (2)0.302 (2)0.049 (6)*
H1O30.311 (3)0.266 (2)0.7732 (18)0.038 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0232 (5)0.0259 (5)0.0132 (4)0.0063 (4)0.0045 (4)0.0032 (4)
O20.0192 (5)0.0202 (4)0.0187 (5)0.0078 (3)0.0065 (4)0.0011 (4)
O30.0171 (4)0.0197 (4)0.0178 (5)0.0004 (3)0.0076 (3)0.0008 (4)
N10.0144 (5)0.0132 (4)0.0126 (5)0.0025 (4)0.0037 (4)0.0030 (4)
C10.0172 (6)0.0146 (5)0.0154 (6)0.0012 (4)0.0019 (4)0.0055 (4)
C20.0142 (6)0.0200 (6)0.0225 (6)0.0028 (4)0.0044 (5)0.0100 (5)
C30.0185 (6)0.0192 (6)0.0198 (6)0.0053 (5)0.0085 (5)0.0079 (5)
C40.0210 (6)0.0139 (5)0.0132 (6)0.0029 (4)0.0044 (5)0.0047 (4)
C50.0142 (5)0.0140 (5)0.0157 (6)0.0014 (4)0.0035 (4)0.0058 (4)
C60.0158 (6)0.0109 (5)0.0151 (6)0.0014 (4)0.0044 (4)0.0053 (4)
C70.0136 (5)0.0147 (5)0.0141 (6)0.0003 (4)0.0021 (4)0.0058 (4)
C80.0129 (5)0.0137 (5)0.0142 (6)0.0008 (4)0.0025 (4)0.0053 (4)
C90.0147 (6)0.0152 (5)0.0151 (6)0.0001 (4)0.0029 (4)0.0049 (4)
C100.0138 (5)0.0141 (5)0.0126 (5)0.0005 (4)0.0015 (4)0.0042 (4)
C110.0148 (6)0.0151 (5)0.0116 (5)0.0017 (4)0.0029 (4)0.0031 (4)
C120.0137 (5)0.0148 (5)0.0147 (6)0.0007 (4)0.0043 (4)0.0037 (4)
C130.0142 (5)0.0140 (5)0.0137 (6)0.0012 (4)0.0014 (4)0.0039 (4)
C140.0155 (6)0.0136 (5)0.0124 (5)0.0009 (4)0.0029 (4)0.0056 (4)
C150.0153 (6)0.0142 (5)0.0118 (5)0.0013 (4)0.0019 (4)0.0036 (4)
C160.0153 (6)0.0151 (5)0.0152 (6)0.0017 (4)0.0045 (4)0.0058 (4)
C170.0230 (6)0.0145 (5)0.0130 (6)0.0006 (5)0.0044 (5)0.0035 (4)
C180.0191 (6)0.0149 (5)0.0138 (6)0.0036 (4)0.0004 (4)0.0052 (4)
C190.0146 (6)0.0175 (5)0.0146 (6)0.0008 (4)0.0022 (4)0.0070 (5)
C200.0183 (6)0.0153 (5)0.0188 (6)0.0044 (4)0.0047 (5)0.0039 (5)
Geometric parameters (Å, º) top
O1—C41.3596 (15)C9—C101.4908 (16)
O1—H1O10.96 (2)C10—C131.3476 (16)
O2—C91.2351 (14)C10—C111.5051 (15)
O3—C161.3674 (14)C11—H11A0.9900
O3—H1O30.87 (2)C11—H11B0.9900
N1—C121.4668 (15)C12—H12A0.9900
N1—C201.4684 (14)C12—H12B0.9900
N1—C111.4697 (15)C13—C141.4595 (16)
C1—C21.3868 (17)C13—H13A0.9500
C1—C61.3996 (17)C14—C151.4030 (16)
C1—H1A0.9500C14—C191.4038 (16)
C2—C31.3824 (18)C15—C161.3912 (16)
C2—H2A0.9500C15—H15A0.9500
C3—C41.3944 (18)C16—C171.3915 (17)
C3—H3A0.9500C17—C181.3871 (17)
C4—C51.3910 (16)C17—H17A0.9500
C5—C61.4064 (16)C18—C191.3872 (17)
C5—H5A0.9500C18—H18A0.9500
C6—C71.4625 (16)C19—H19A0.9500
C7—C81.3472 (16)C20—H20A0.9800
C7—H7A0.9500C20—H20B0.9800
C8—C91.4819 (16)C20—H20C0.9800
C8—C121.5076 (15)
C4—O1—H1O1112.0 (13)C10—C11—H11A109.3
C16—O3—H1O3108.1 (12)N1—C11—H11B109.3
C12—N1—C20110.15 (9)C10—C11—H11B109.3
C12—N1—C11109.61 (9)H11A—C11—H11B108.0
C20—N1—C11109.52 (9)N1—C12—C8110.31 (9)
C2—C1—C6119.72 (11)N1—C12—H12A109.6
C2—C1—H1A120.1C8—C12—H12A109.6
C6—C1—H1A120.1N1—C12—H12B109.6
C3—C2—C1120.94 (11)C8—C12—H12B109.6
C3—C2—H2A119.5H12A—C12—H12B108.1
C1—C2—H2A119.5C10—C13—C14130.67 (11)
C2—C3—C4120.23 (11)C10—C13—H13A114.7
C2—C3—H3A119.9C14—C13—H13A114.7
C4—C3—H3A119.9C15—C14—C19118.59 (11)
O1—C4—C5123.05 (11)C15—C14—C13116.26 (10)
O1—C4—C3117.67 (11)C19—C14—C13125.13 (11)
C5—C4—C3119.27 (11)C16—C15—C14121.15 (11)
C4—C5—C6120.74 (11)C16—C15—H15A119.4
C4—C5—H5A119.6C14—C15—H15A119.4
C6—C5—H5A119.6O3—C16—C15121.89 (11)
C1—C6—C5119.07 (11)O3—C16—C17118.25 (11)
C1—C6—C7122.82 (11)C15—C16—C17119.85 (11)
C5—C6—C7117.90 (10)C18—C17—C16119.08 (11)
C8—C7—C6129.38 (11)C18—C17—H17A120.5
C8—C7—H7A115.3C16—C17—H17A120.5
C6—C7—H7A115.3C17—C18—C19121.80 (11)
C7—C8—C9117.96 (10)C17—C18—H18A119.1
C7—C8—C12124.30 (10)C19—C18—H18A119.1
C9—C8—C12117.72 (10)C18—C19—C14119.49 (11)
O2—C9—C8121.55 (11)C18—C19—H19A120.3
O2—C9—C10120.44 (11)C14—C19—H19A120.3
C8—C9—C10118.00 (10)N1—C20—H20A109.5
C13—C10—C9116.70 (10)N1—C20—H20B109.5
C13—C10—C11124.79 (10)H20A—C20—H20B109.5
C9—C10—C11118.51 (10)N1—C20—H20C109.5
N1—C11—C10111.60 (9)H20A—C20—H20C109.5
N1—C11—H11A109.3H20B—C20—H20C109.5
C6—C1—C2—C30.52 (18)C12—N1—C11—C1060.87 (12)
C1—C2—C3—C41.06 (18)C20—N1—C11—C10178.18 (10)
C2—C3—C4—O1179.88 (11)C13—C10—C11—N1152.54 (12)
C2—C3—C4—C51.56 (18)C9—C10—C11—N126.59 (15)
O1—C4—C5—C6178.98 (11)C20—N1—C12—C8174.22 (9)
C3—C4—C5—C60.50 (17)C11—N1—C12—C865.22 (12)
C2—C1—C6—C51.56 (17)C7—C8—C12—N1142.85 (12)
C2—C1—C6—C7172.99 (11)C9—C8—C12—N135.19 (14)
C4—C5—C6—C11.06 (17)C9—C10—C13—C14179.80 (12)
C4—C5—C6—C7173.76 (10)C11—C10—C13—C140.7 (2)
C1—C6—C7—C831.69 (19)C10—C13—C14—C15160.79 (13)
C5—C6—C7—C8153.70 (12)C10—C13—C14—C1920.9 (2)
C6—C7—C8—C9174.71 (11)C19—C14—C15—C162.09 (18)
C6—C7—C8—C127.3 (2)C13—C14—C15—C16179.43 (11)
C7—C8—C9—O24.94 (18)C14—C15—C16—O3179.37 (11)
C12—C8—C9—O2176.91 (11)C14—C15—C16—C170.52 (18)
C7—C8—C9—C10176.05 (11)O3—C16—C17—C18177.59 (11)
C12—C8—C9—C102.11 (16)C15—C16—C17—C181.30 (18)
O2—C9—C10—C130.53 (18)C16—C17—C18—C191.55 (19)
C8—C9—C10—C13178.49 (11)C17—C18—C19—C140.05 (18)
O2—C9—C10—C11178.66 (11)C15—C14—C19—C181.85 (17)
C8—C9—C10—C112.31 (17)C13—C14—C19—C18179.83 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O1···N1i0.96 (2)1.81 (2)2.7278 (14)160 (2)
O3—H1O3···O2ii0.88 (2)1.87 (2)2.7359 (15)171 (2)
C17—H17A···O3iii0.952.513.4032 (16)157
Symmetry codes: (i) x+2, y, z; (ii) x+1, y, z+1; (iii) x+1, y+1, z+2.
(2) 3,5-Bis[(E)-2-chlorobenzylidene]-1-methylpiperidin-4-one top
Crystal data top
C20H17Cl2NOF(000) = 744
Mr = 358.24Dx = 1.423 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 7.540 (3) ÅCell parameters from 3908 reflections
b = 10.623 (4) Åθ = 2.7–29.2°
c = 21.119 (7) ŵ = 0.39 mm1
β = 98.671 (5)°T = 100 K
V = 1672.2 (10) Å3Needle, yellow
Z = 40.32 × 0.08 × 0.08 mm
Data collection top
Bruker APEX DUO CCD area-detector
diffractometer
2591 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.084
φ and ω scansθmax = 25.5°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 99
k = 1212
3105 measured reflectionsl = 525
3105 independent 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)] = 0.077Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.192H-atom parameters constrained
S = 1.18 w = 1/[σ2(Fo2) + 13.4429P]
where P = (Fo2 + 2Fc2)/3
3105 reflections(Δ/σ)max < 0.001
218 parametersΔρmax = 0.45 e Å3
0 restraintsΔρmin = 0.43 e Å3
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 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. Refined as a 2-component twin.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.8841 (2)0.46525 (14)0.06491 (7)0.0261 (4)
Cl20.6925 (2)0.18217 (14)0.22186 (7)0.0242 (4)
O10.6046 (5)0.0962 (4)0.04698 (18)0.0193 (9)
N10.9749 (6)0.1131 (4)0.0667 (2)0.0179 (10)
C10.7905 (8)0.1999 (6)0.1897 (3)0.0205 (13)
H1A0.74920.11530.18920.025*
C20.8325 (8)0.2615 (6)0.2487 (3)0.0244 (13)
H2A0.81930.21990.28760.029*
C30.8940 (8)0.3854 (6)0.2491 (3)0.0263 (14)
H3A0.92660.42750.28890.032*
C40.9085 (8)0.4479 (6)0.1928 (3)0.0264 (14)
H4A0.94770.53290.19340.032*
C50.8648 (8)0.3841 (5)0.1355 (3)0.0182 (12)
C60.8072 (7)0.2581 (5)0.1317 (3)0.0178 (12)
C70.7554 (7)0.1956 (5)0.0699 (3)0.0184 (12)
H7A0.69650.24610.03590.022*
C80.7825 (7)0.0744 (5)0.0562 (3)0.0156 (12)
C90.7007 (7)0.0275 (6)0.0089 (3)0.0181 (12)
C100.7323 (7)0.1071 (5)0.0242 (3)0.0158 (12)
C110.8378 (8)0.1877 (5)0.0269 (3)0.0186 (12)
H11A0.75550.22500.05420.022*
H11B0.89590.25730.00660.022*
C120.8874 (8)0.0179 (5)0.1009 (3)0.0179 (12)
H12A0.97940.02790.13050.021*
H12B0.80560.05980.12680.021*
C130.6595 (7)0.1495 (5)0.0815 (3)0.0165 (12)
H13A0.60440.08780.11060.020*
C140.6534 (7)0.2798 (5)0.1058 (3)0.0161 (12)
C150.6583 (7)0.3058 (5)0.1704 (3)0.0185 (12)
C160.6392 (8)0.4257 (6)0.1957 (3)0.0210 (13)
H16A0.64200.43970.24000.025*
C170.6158 (8)0.5253 (6)0.1554 (3)0.0229 (13)
H17A0.60320.60840.17210.027*
C180.6106 (8)0.5046 (6)0.0912 (3)0.0210 (13)
H18A0.59490.57290.06350.025*
C190.6288 (7)0.3818 (5)0.0674 (3)0.0187 (12)
H19A0.62420.36790.02320.022*
C201.0862 (8)0.1939 (6)0.1114 (3)0.0225 (13)
H20A1.14400.25730.08770.034*
H20B1.17830.14320.13750.034*
H20C1.01170.23590.13930.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0287 (8)0.0196 (7)0.0305 (8)0.0023 (6)0.0065 (6)0.0026 (6)
Cl20.0292 (8)0.0260 (8)0.0176 (7)0.0003 (6)0.0038 (6)0.0015 (6)
O10.020 (2)0.018 (2)0.019 (2)0.0055 (17)0.0001 (17)0.0049 (17)
N10.012 (2)0.019 (3)0.022 (2)0.002 (2)0.000 (2)0.002 (2)
C10.019 (3)0.020 (3)0.023 (3)0.003 (2)0.005 (2)0.002 (2)
C20.019 (3)0.027 (3)0.027 (3)0.006 (3)0.002 (3)0.002 (3)
C30.023 (3)0.029 (4)0.027 (3)0.007 (3)0.002 (3)0.012 (3)
C40.021 (3)0.023 (3)0.035 (4)0.001 (3)0.001 (3)0.005 (3)
C50.016 (3)0.015 (3)0.023 (3)0.001 (2)0.003 (2)0.004 (2)
C60.012 (3)0.018 (3)0.023 (3)0.003 (2)0.004 (2)0.003 (2)
C70.014 (3)0.019 (3)0.023 (3)0.001 (2)0.005 (2)0.004 (2)
C80.015 (3)0.015 (3)0.019 (3)0.000 (2)0.007 (2)0.002 (2)
C90.013 (3)0.025 (3)0.018 (3)0.004 (2)0.007 (2)0.000 (2)
C100.013 (3)0.018 (3)0.017 (3)0.003 (2)0.006 (2)0.004 (2)
C110.020 (3)0.017 (3)0.019 (3)0.000 (2)0.003 (2)0.003 (2)
C120.019 (3)0.017 (3)0.018 (3)0.000 (2)0.004 (2)0.005 (2)
C130.016 (3)0.019 (3)0.014 (3)0.000 (2)0.002 (2)0.000 (2)
C140.011 (3)0.020 (3)0.017 (3)0.002 (2)0.002 (2)0.001 (2)
C150.015 (3)0.020 (3)0.020 (3)0.001 (2)0.002 (2)0.002 (2)
C160.020 (3)0.026 (3)0.017 (3)0.000 (3)0.001 (2)0.005 (2)
C170.023 (3)0.018 (3)0.027 (3)0.004 (3)0.001 (3)0.008 (3)
C180.018 (3)0.024 (3)0.020 (3)0.003 (3)0.001 (2)0.001 (2)
C190.016 (3)0.021 (3)0.019 (3)0.001 (2)0.001 (2)0.004 (2)
C200.025 (3)0.020 (3)0.022 (3)0.002 (3)0.001 (3)0.001 (2)
Geometric parameters (Å, º) top
Cl1—C51.747 (6)C10—C131.331 (8)
Cl2—C151.749 (6)C10—C111.508 (8)
O1—C91.236 (7)C11—H11A0.9900
N1—C201.447 (7)C11—H11B0.9900
N1—C121.457 (7)C12—H12A0.9900
N1—C111.462 (7)C12—H12B0.9900
C1—C61.396 (8)C13—C141.474 (8)
C1—C21.402 (8)C13—H13A0.9500
C1—H1A0.9500C14—C191.383 (8)
C2—C31.395 (9)C14—C151.398 (8)
C2—H2A0.9500C15—C161.381 (8)
C3—C41.381 (9)C16—C171.386 (8)
C3—H3A0.9500C16—H16A0.9500
C4—C51.382 (8)C17—C181.381 (8)
C4—H4A0.9500C17—H17A0.9500
C5—C61.406 (8)C18—C191.397 (8)
C6—C71.464 (8)C18—H18A0.9500
C7—C81.343 (8)C19—H19A0.9500
C7—H7A0.9500C20—H20A0.9800
C8—C121.501 (8)C20—H20B0.9800
C8—C91.505 (8)C20—H20C0.9800
C9—C101.492 (8)
C20—N1—C12110.4 (4)N1—C11—H11B109.5
C20—N1—C11110.1 (5)C10—C11—H11B109.5
C12—N1—C11109.1 (4)H11A—C11—H11B108.1
C6—C1—C2122.4 (6)N1—C12—C8112.1 (4)
C6—C1—H1A118.8N1—C12—H12A109.2
C2—C1—H1A118.8C8—C12—H12A109.2
C3—C2—C1118.5 (6)N1—C12—H12B109.2
C3—C2—H2A120.8C8—C12—H12B109.2
C1—C2—H2A120.8H12A—C12—H12B107.9
C4—C3—C2121.2 (6)C10—C13—C14128.4 (5)
C4—C3—H3A119.4C10—C13—H13A115.8
C2—C3—H3A119.4C14—C13—H13A115.8
C3—C4—C5118.6 (6)C19—C14—C15116.3 (5)
C3—C4—H4A120.7C19—C14—C13122.2 (5)
C5—C4—H4A120.7C15—C14—C13121.4 (5)
C4—C5—C6123.2 (6)C16—C15—C14122.9 (5)
C4—C5—Cl1117.7 (5)C16—C15—Cl2118.0 (4)
C6—C5—Cl1119.0 (5)C14—C15—Cl2119.1 (4)
C1—C6—C5116.1 (5)C15—C16—C17118.8 (5)
C1—C6—C7122.3 (5)C15—C16—H16A120.6
C5—C6—C7121.5 (5)C17—C16—H16A120.6
C8—C7—C6126.7 (5)C18—C17—C16120.4 (6)
C8—C7—H7A116.6C18—C17—H17A119.8
C6—C7—H7A116.6C16—C17—H17A119.8
C7—C8—C12125.1 (5)C17—C18—C19119.1 (6)
C7—C8—C9117.3 (5)C17—C18—H18A120.4
C12—C8—C9117.6 (5)C19—C18—H18A120.4
O1—C9—C10121.5 (5)C14—C19—C18122.4 (5)
O1—C9—C8121.2 (5)C14—C19—H19A118.8
C10—C9—C8117.2 (5)C18—C19—H19A118.8
C13—C10—C9117.6 (5)N1—C20—H20A109.5
C13—C10—C11124.0 (5)N1—C20—H20B109.5
C9—C10—C11118.3 (5)H20A—C20—H20B109.5
N1—C11—C10110.7 (5)N1—C20—H20C109.5
N1—C11—H11A109.5H20A—C20—H20C109.5
C10—C11—H11A109.5H20B—C20—H20C109.5
C6—C1—C2—C30.4 (9)C20—N1—C11—C10174.5 (4)
C1—C2—C3—C42.0 (9)C12—N1—C11—C1064.2 (6)
C2—C3—C4—C51.6 (9)C13—C10—C11—N1149.3 (5)
C3—C4—C5—C60.5 (9)C9—C10—C11—N133.2 (7)
C3—C4—C5—Cl1180.0 (5)C20—N1—C12—C8175.3 (5)
C2—C1—C6—C51.5 (8)C11—N1—C12—C863.6 (6)
C2—C1—C6—C7177.1 (5)C7—C8—C12—N1149.2 (5)
C4—C5—C6—C11.9 (8)C9—C8—C12—N131.0 (7)
Cl1—C5—C6—C1178.5 (4)C9—C10—C13—C14172.8 (5)
C4—C5—C6—C7177.6 (5)C11—C10—C13—C144.8 (9)
Cl1—C5—C6—C72.9 (7)C10—C13—C14—C1937.6 (9)
C1—C6—C7—C839.9 (9)C10—C13—C14—C15147.5 (6)
C5—C6—C7—C8144.7 (6)C19—C14—C15—C160.3 (8)
C6—C7—C8—C125.9 (9)C13—C14—C15—C16175.0 (5)
C6—C7—C8—C9173.9 (5)C19—C14—C15—Cl2179.0 (4)
C7—C8—C9—O13.8 (8)C13—C14—C15—Cl25.8 (7)
C12—C8—C9—O1176.1 (5)C14—C15—C16—C170.6 (9)
C7—C8—C9—C10179.6 (5)Cl2—C15—C16—C17178.6 (4)
C12—C8—C9—C100.6 (7)C15—C16—C17—C180.4 (9)
O1—C9—C10—C132.9 (8)C16—C17—C18—C190.2 (9)
C8—C9—C10—C13179.6 (5)C15—C14—C19—C180.3 (8)
O1—C9—C10—C11174.7 (5)C13—C14—C19—C18175.5 (5)
C8—C9—C10—C111.9 (7)C17—C18—C19—C140.5 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4A···Cl2i0.952.853.587 (7)135
Symmetry code: (i) x+1/2, y+1/2, z+1/2.
 

Acknowledgements

The authors are grateful to the Ministry of Education and Culture of Indonesia for financial support (research grant No. 2013 for YE) and the Universiti Sains Malaysia for the X-ray measurements.

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