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

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ISSN: 2056-9890
Volume 68| Part 11| November 2012| Pages m1323-m1324

N,N′-bis­­[(3-hy­dr­oxy-4(4H)-oxypyran-2-yl)meth­yl]-N,N′-di­methyl­ethylene-1,2-di­ammonium tetra­chloridoplatinate(II) dihydrate

aDepartment of Basic Sciences and Fundamentals, University of Urbino, I-61029 Urbino, Italy, and bDip. Energetica `Sergio Stecco', University of Firenze, Via S. Marta 3, I-50139 Firenze, Italy
*Correspondence e-mail: paolapaoli@unifi.it

(Received 10 September 2012; accepted 28 September 2012; online 6 October 2012)

The title compound (C16H22N2O6)[PtCl4]·2H2O, shows anti­proliferative activity in eight tumor cell lines. The asymmetric unit consists of one solvent water mol­ecule on a general position, and one half of each of the polyammonium cation and the tetrachloridoplatinate(II) anion, both of them located on centers of inversion. In the crystal, the cations are connected via hydrogen bonding between the carbonyl O atoms and the hydroxyl H atoms into zigzag chains that elongate in the c-axis direction. In addition, the carbonyl O atom is hydrogen-bonded to the water mol­ecule which, in turn, inter­acts with the [PtCl4]2− anion. Finally, the chains are linked by N—H+⋯Cl inter­actions into a three-dimensional network.

Related literature

For the anti­tumor activity of maltol (systematic name: 3-hy­droxy-2-methyl-4-pyrone) and polyamines, see: Casero & Woster (2001[Casero, R. A. J. & Woster, P. M. J. (2001). Med. Chem. 44, 1-26.]); Liang et al. (2006[Liang, F., Wan, S., Li, Z., Xiong, X., Yang, L., Zhou, X. & Wu, C. (2006). Curr. Med. Chem. 13, 711-727.]); Murakami et al. (2006[Murakami, K., Ishida, K., Watakabe, K., Tsubouchi, R., Naruse, M. & Yoshino, M. (2006). Toxicol. Lett. 161, 102-107.]). For background to the synthesis, solution behaviour, structural properties and biological activity of N,N′-bis­[(3-hy­droxy-4-pyron-2-yl)meth­yl]-N,N′-dimethyl­ethylendiamine (Malten), see: Amatori et al. (2010[Amatori, S., Bagaloni, I., Fanelli, M., Formica, M., Fusi, V., Giorgi, L. & Macedi, E. (2010). Br. J. Cancer, 103, 239-248.], 2012[Amatori, S., Ambrosi, G., Fanelli, M., Formica, M., Fusi, V., Giorgi, L., Macedi, E., Micheloni, M., Paoli, P., Pontellini, R. & Rossi, P. (2012). J. Org. Chem. 77, 2207-2218.]).

[Scheme 1]

Experimental

Crystal data
  • (C16H22N2O6)[PtCl4]·2H2O

  • Mr = 711.28

  • Triclinic, [P \overline 1]

  • a = 6.4775 (4) Å

  • b = 7.0037 (4) Å

  • c = 13.1628 (8) Å

  • α = 88.810 (5)°

  • β = 87.033 (5)°

  • γ = 71.927 (6)°

  • V = 566.92 (6) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 6.71 mm−1

  • T = 150 K

  • 0.32 × 0.22 × 0.20 mm

Data collection
  • Oxford Diffraction Xcalibur3 diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]) Tmin = 0.164, Tmax = 0.262

  • 9431 measured reflections

  • 2719 independent reflections

  • 2694 reflections with I > 2σ(I)

  • Rint = 0.044

Refinement
  • R[F2 > 2σ(F2)] = 0.023

  • wR(F2) = 0.049

  • S = 1.02

  • 2719 reflections

  • 158 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 1.44 e Å−3

  • Δρmin = −1.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O⋯O2i 0.73 (4) 1.98 (4) 2.655 (4) 154 (4)
O1W—H1WB⋯O2ii 0.79 (5) 2.07 (5) 2.853 (4) 171 (5)
O1W—H1WA⋯Cl2 0.84 (5) 2.45 (5) 3.282 (3) 174 (5)
N1—H1N⋯Cl1iii 0.74 (4) 2.79 (4) 3.380 (3) 139 (4)
N1—H1N⋯Cl1iv 0.74 (4) 2.79 (4) 3.362 (3) 136 (4)
Symmetry codes: (i) -x+2, -y+1, -z; (ii) -x+2, -y, -z; (iii) -x+2, -y+1, -z+1; (iv) x-1, y+1, z.

Data collection: CrysAlis PRO (Oxford Diffraction 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: PARST97 (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]).

Supporting information


Comment top

Maltol (3-hydroxy-2-methyl-4-pyrone) is a natural compound, which exhibits interesting antineoplastic activities (Murakami et al., 2006). At the same time, linear polyamines are also known antitumor agents (Liang et al., 2006; Casero & Woster, 2001). For these reasons we synthesized and studied compound N,N'-bis((3-hydroxy-4-pyron-2-yl)methyl)-N,N'-dimethylethylendiamine (Malten) coupling two Maltol units to an aliphatic diamine. Malten has shown antiproliferative activity in eight tumor cell lines (Amatori et al.,2010; Amatori et al., 2012). In the asymmetric unit of the title compound half of the polyammonium cation [H2Malten]2+ and of the tetrachloroplatinate(II) counterion are present, together with a crystallization water molecule. The two halves of each ion are related by a center of symmetry (Fig. 1). The [H2Malten]2+ polyammonium chain, which joins the two aromatic rings, has an all-trans conformation and defines a plane which forms an angle of 65.4 (2)° with each of them. In the crystal lattice the [H2Malten]2+ cations are each linked by two pairs of complementary O—H···O hydrogen bonds into centrosymmetric dimers, which are further linked into chains along the c axis (Fig. 2 and Table 1). Moreover, the carbonyl O atom (O2) is H-bonded to the lattice water molecule, which is also linked to the (PtCl4)2- anion by O—H···Cl interactions. Finally, the cations and anions are linked by N—H+···Cl interactions.

Related literature top

For the antitumor activity of maltol (systematic name: 3-hydroxy-2-methyl-4-pyrone) and polyamines, see: Casero & Woster (2001); Liang et al. (2006); Murakami et al. (2006). For background to the synthesis, solution behaviour, structural properties and biological activity of N,N'-bis[(3-hydroxy-4-pyron-2-yl)methyl]-N,N'-dimethylethylendiamine (Malten), see: Amatori et al. (2010, 2012).

Experimental top

Malten.2HClO4 was dissolved in H2O, K2PtCl4 was added and the pH adjusted to 3. Crystals suitable for X-ray analysis formed in one day at room temperature.

Refinement top

The O—H and N—H H atoms were located in the Fourier difference map and refined with varying coordinates isotropic. The C—H H atoms were introduced in calculated position and refined isotropic with Uiso(H) 1.2 times Ueq(C) (1.5 for methyl H atoms).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction 2009); cell refinement: CrysAlis PRO (Oxford Diffraction 2009); data reduction: CrysAlis PRO (Oxford Diffraction 2009); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PARST97 (Nardelli, 1995).

Figures top
[Figure 1] Fig. 1. Crystal structure of the title compound with labelling and displacement ellipsoids drawn at the 30% probability level. Symmetry codes: i) = -x + 2, -y, -z + 1; ii) = -x + 1, -y + 1, -z + 1.
[Figure 2] Fig. 2. Crystal structure of the title compound with view along the a axis. Intermolecular hydrogen bonding is shown as dashed lines.
N,N'-bis[(3-hydroxy-4(4H)-oxypyran-2-yl)methyl]-N, N'-dimethylethylene-1,2-diammonium tetrachloridoplatinate(II) dihydrate top
Crystal data top
(C16H22N2O6)[PtCl4]·2H2OZ = 1
Mr = 711.28F(000) = 346
Triclinic, P1Dx = 2.083 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.4775 (4) ÅCell parameters from 7279 reflections
b = 7.0037 (4) Åθ = 4.1–29.2°
c = 13.1628 (8) ŵ = 6.71 mm1
α = 88.810 (5)°T = 150 K
β = 87.033 (5)°Prismatic, light yellow
γ = 71.927 (6)°0.32 × 0.22 × 0.20 mm
V = 566.92 (6) Å3
Data collection top
Oxford Diffraction Xcalibur3
diffractometer
2719 independent reflections
Radiation source: Enhance (Mo) X-ray Source2694 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.044
Detector resolution: 16.4547 pixels mm-1θmax = 29.3°, θmin = 4.1°
ω scansh = 88
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction 2009)
k = 99
Tmin = 0.164, Tmax = 0.262l = 1717
9431 measured 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)] = 0.023Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.049H atoms treated by a mixture of independent and constrained refinement
S = 1.02 w = 1/[σ2(Fo2) + (0.0253P)2]
where P = (Fo2 + 2Fc2)/3
2719 reflections(Δ/σ)max < 0.001
158 parametersΔρmax = 1.44 e Å3
0 restraintsΔρmin = 1.14 e Å3
Crystal data top
(C16H22N2O6)[PtCl4]·2H2Oγ = 71.927 (6)°
Mr = 711.28V = 566.92 (6) Å3
Triclinic, P1Z = 1
a = 6.4775 (4) ÅMo Kα radiation
b = 7.0037 (4) ŵ = 6.71 mm1
c = 13.1628 (8) ÅT = 150 K
α = 88.810 (5)°0.32 × 0.22 × 0.20 mm
β = 87.033 (5)°
Data collection top
Oxford Diffraction Xcalibur3
diffractometer
2719 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction 2009)
2694 reflections with I > 2σ(I)
Tmin = 0.164, Tmax = 0.262Rint = 0.044
9431 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0230 restraints
wR(F2) = 0.049H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 1.44 e Å3
2719 reflectionsΔρmin = 1.14 e Å3
158 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Pt11.00000.00000.50000.01531 (6)
Cl11.25762 (12)0.12554 (11)0.42237 (6)0.01926 (15)
Cl20.82520 (13)0.02992 (11)0.34889 (6)0.02098 (16)
O10.8029 (5)0.6477 (4)0.1284 (2)0.0298 (6)
O20.8598 (4)0.3386 (4)0.00821 (17)0.0278 (5)
O30.3953 (4)0.4312 (3)0.22157 (16)0.0218 (5)
N10.5757 (4)0.6487 (4)0.3876 (2)0.0169 (5)
C10.4294 (6)0.2757 (5)0.1565 (3)0.0261 (7)
H10.34240.19240.16490.031*
C20.5823 (6)0.2365 (5)0.0809 (3)0.0263 (7)
H20.59980.12630.03940.032*
C30.7197 (5)0.3601 (5)0.0625 (2)0.0224 (7)
C40.6815 (5)0.5228 (5)0.1358 (2)0.0205 (6)
C50.5256 (5)0.5510 (5)0.2108 (2)0.0187 (6)
C60.4731 (5)0.7161 (5)0.2869 (2)0.0190 (6)
H6A0.31660.76820.29840.023*
H6B0.52330.82440.25950.023*
C70.4568 (5)0.5266 (5)0.4470 (2)0.0181 (6)
H7A0.47190.40390.41030.022*
H7B0.30330.60180.45320.022*
C150.8152 (5)0.5442 (5)0.3735 (2)0.0181 (6)
H15A0.88210.62900.33510.027*
H15B0.83890.42070.33760.027*
H15C0.87780.51590.43880.027*
O1W1.1440 (5)0.0251 (4)0.1423 (2)0.0343 (6)
H1N0.559 (6)0.742 (6)0.417 (3)0.028 (11)*
H1O0.888 (7)0.623 (6)0.088 (3)0.024 (11)*
H1WA1.062 (9)0.020 (8)0.194 (4)0.059 (16)*
H1WB1.128 (7)0.105 (7)0.104 (3)0.040 (13)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Pt10.01339 (9)0.01279 (9)0.02021 (9)0.00476 (6)0.00072 (6)0.00306 (6)
Cl10.0169 (4)0.0185 (4)0.0241 (4)0.0084 (3)0.0032 (3)0.0031 (3)
Cl20.0223 (4)0.0208 (4)0.0219 (4)0.0092 (3)0.0040 (3)0.0009 (3)
O10.0347 (15)0.0327 (14)0.0275 (13)0.0200 (12)0.0137 (12)0.0108 (11)
O20.0310 (14)0.0309 (13)0.0237 (12)0.0136 (11)0.0074 (10)0.0087 (10)
O30.0236 (12)0.0246 (12)0.0197 (11)0.0112 (10)0.0005 (9)0.0021 (9)
N10.0197 (14)0.0154 (13)0.0168 (12)0.0074 (11)0.0002 (10)0.0020 (10)
C10.0284 (19)0.0261 (18)0.0283 (17)0.0143 (15)0.0056 (15)0.0001 (14)
C20.0310 (19)0.0242 (17)0.0271 (17)0.0134 (15)0.0003 (15)0.0062 (13)
C30.0251 (18)0.0222 (16)0.0196 (15)0.0064 (13)0.0035 (13)0.0020 (12)
C40.0236 (17)0.0208 (16)0.0191 (15)0.0096 (13)0.0003 (13)0.0030 (12)
C50.0218 (16)0.0177 (15)0.0172 (14)0.0065 (13)0.0041 (13)0.0014 (11)
C60.0220 (16)0.0170 (15)0.0170 (14)0.0047 (12)0.0027 (12)0.0018 (11)
C70.0171 (15)0.0176 (15)0.0200 (15)0.0060 (12)0.0006 (12)0.0009 (11)
C150.0158 (15)0.0189 (15)0.0194 (14)0.0051 (12)0.0007 (12)0.0008 (11)
O1W0.0380 (17)0.0383 (16)0.0315 (15)0.0187 (13)0.0001 (13)0.0064 (12)
Geometric parameters (Å, º) top
Pt1—Cl1i2.3018 (8)C2—C31.431 (5)
Pt1—Cl12.3018 (8)C2—H20.9300
Pt1—Cl2i2.3132 (7)C3—C41.462 (4)
Pt1—Cl22.3132 (7)C4—C51.348 (5)
O1—C41.345 (4)C5—C61.491 (4)
O1—H1O0.73 (4)C6—H6A0.9700
O2—C31.243 (4)C6—H6B0.9700
O3—C11.356 (4)C7—C7ii1.526 (6)
O3—C51.363 (4)C7—H7A0.9700
N1—C151.499 (4)C7—H7B0.9700
N1—C71.501 (4)C15—H15A0.9600
N1—C61.514 (4)C15—H15B0.9600
N1—H1N0.74 (4)C15—H15C0.9600
C1—C21.337 (5)O1W—H1WA0.84 (5)
C1—H10.9300O1W—H1WB0.79 (5)
Cl1i—Pt1—Cl1180.00 (4)O1—C4—C3119.7 (3)
Cl1i—Pt1—Cl2i90.28 (3)C5—C4—C3121.2 (3)
Cl1—Pt1—Cl2i89.72 (3)C4—C5—O3121.9 (3)
Cl1i—Pt1—Cl289.72 (3)C4—C5—C6124.4 (3)
Cl1—Pt1—Cl290.28 (3)O3—C5—C6113.7 (3)
Cl2i—Pt1—Cl2180.0C5—C6—N1112.9 (2)
C4—O1—H1O115 (3)C5—C6—H6A109.0
C1—O3—C5118.6 (3)N1—C6—H6A109.0
C15—N1—C7113.3 (2)C5—C6—H6B109.0
C15—N1—C6111.5 (2)N1—C6—H6B109.0
C7—N1—C6110.8 (2)H6A—C6—H6B107.8
C15—N1—H1N109 (3)N1—C7—C7ii111.9 (3)
C7—N1—H1N107 (3)N1—C7—H7A109.2
C6—N1—H1N106 (3)C7ii—C7—H7A109.2
C2—C1—O3123.1 (3)N1—C7—H7B109.2
C2—C1—H1118.5C7ii—C7—H7B109.2
O3—C1—H1118.5H7A—C7—H7B107.9
C1—C2—C3121.5 (3)N1—C15—H15A109.5
C1—C2—H2119.2N1—C15—H15B109.5
C3—C2—H2119.2H15A—C15—H15B109.5
O2—C3—C2125.6 (3)N1—C15—H15C109.5
O2—C3—C4120.7 (3)H15A—C15—H15C109.5
C2—C3—C4113.7 (3)H15B—C15—H15C109.5
O1—C4—C5119.1 (3)H1WA—O1W—H1WB109 (5)
Symmetry codes: (i) x+2, y, z+1; (ii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O2iii0.73 (4)1.98 (4)2.655 (4)154 (4)
O1W—H1WB···O2iv0.79 (5)2.07 (5)2.853 (4)171 (4)
O1W—H1WA···Cl20.84 (5)2.45 (5)3.282 (3)174 (5)
N1—H1N···Cl1v0.74 (4)2.79 (4)3.380 (3)139 (4)
N1—H1N···Cl1vi0.74 (4)2.79 (4)3.362 (3)136 (4)
Symmetry codes: (iii) x+2, y+1, z; (iv) x+2, y, z; (v) x+2, y+1, z+1; (vi) x1, y+1, z.

Experimental details

Crystal data
Chemical formula(C16H22N2O6)[PtCl4]·2H2O
Mr711.28
Crystal system, space groupTriclinic, P1
Temperature (K)150
a, b, c (Å)6.4775 (4), 7.0037 (4), 13.1628 (8)
α, β, γ (°)88.810 (5), 87.033 (5), 71.927 (6)
V3)566.92 (6)
Z1
Radiation typeMo Kα
µ (mm1)6.71
Crystal size (mm)0.32 × 0.22 × 0.20
Data collection
DiffractometerOxford Diffraction Xcalibur3
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction 2009)
Tmin, Tmax0.164, 0.262
No. of measured, independent and
observed [I > 2σ(I)] reflections
9431, 2719, 2694
Rint0.044
(sin θ/λ)max1)0.689
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.023, 0.049, 1.02
No. of reflections2719
No. of parameters158
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)1.44, 1.14

Computer programs: CrysAlis PRO (Oxford Diffraction 2009), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PARST97 (Nardelli, 1995).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O2i0.727 (38)1.983 (43)2.655 (4)154 (4)
O1W—H1WB···O2ii0.794 (51)2.066 (50)2.853 (4)171 (4)
O1W—H1WA···Cl20.837 (52)2.449 (51)3.282 (3)174 (5)
N1—H1N···Cl1iii0.743 (42)2.786 (43)3.380 (3)139 (4)
N1—H1N···Cl1iv0.743 (42)2.788 (36)3.362 (3)136 (4)
Symmetry codes: (i) x+2, y+1, z; (ii) x+2, y, z; (iii) x+2, y+1, z+1; (iv) x1, y+1, z.
 

Acknowledgements

The authors acknowledge CRIST (Centro di Cristallografia Strutturale, University of Firenze), where the data collection was performed, and the Italian Ministero dell'Istruzione dell'Università e della Ricerca (MIUR), PRIN2009, for financial support.

References

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Volume 68| Part 11| November 2012| Pages m1323-m1324
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