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Crystal structure of N-(tert-but­­oxy­carbon­yl)glycyl-(Z)-β-bromo­de­hydro­alanine methyl ester [Boc–Gly–(β-Br)(Z)ΔAla–OMe]

aFaculty of Chemistry, University of Opole, Oleska 48, 45-052 Opole, Poland
*Correspondence e-mail: bzarychta@uni.opole.pl

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 7 November 2014; accepted 24 November 2014; online 29 November 2014)

The title compound, C11H17BrN2O5, is a de­hydro­amino acid with a C=C bond between the α- and β-C atoms. The amino acid residues are linked trans to each other and there are no strong intra­molecular hydrogen bonds. The torsion angles indicate a non-helical conformation of the mol­ecule. The dipeptide folding is influenced by an inter­molecular N—H⋯O hydrogen bond and also minimizes steric repulsion. In the crystal, mol­ecules are linked by strong N—H⋯O hydrogen bonds, generating (001) sheets. The sheets are linked by weak C—H⋯O and C—H⋯Br bonds and short Br⋯Br [3.4149 (3) Å] inter­actions.

1. Chemical context

De­hydro­amino acids are analogues of amino acids characterized by the presence of an unsaturated doubled bound between the α- and β-carbon atoms in their structure. These compounds were found to be components of natural products (Bonauer et al., 2006[Bonauer, C., Walenzyk, T. & König, B. (2006). Synthesis, pp. 1-20.]), with lanti­biotics being especially important since they are an important class of natural bacteriocins produced by Gram-positive bacteria (Willey & van der Donk, 2007[Willey, J. M. & van der Donk, W. A. (2007). Annu. Rev. Microbiol. 61, 477-501.]). The development of synthetic methods for the preparation of de­hydro­peptides allows researchers to search for their practical applications and to use them as substrates for the production of peptidomimetics. One of the inter­esting classes of such mimetics are β-bromo-de­hydro­amino acids and their derivatives, which are usually obtained by radical halogenation of de­hydro­amino acids using N-bromo­succinimide (NBS). This reaction proceeds in two steps, namely by halogenation of de­hydro­amino acids, which gives α-bromo-imines, followed by tautomerization to the desired products upon treatment with an amine (Coleman & Carpenter, 1993[Coleman, R. S. & Carpenter, A. J. (1993). J. Org. Chem. 58, 4452-4461.]; Zhang et al., 2002[Zhang, J. Y., Xiong, C. Y., Wang, W., Ying, J. F. & Hruby, V. J. (2002). Org. Lett. 4, 4029-4032.]). β-Bromo-de­hydro­amino acid derivatives are useful substrates in coupling reactions with alkynes (Singh et al., 2003[Singh, J., Kronenthal, D. R., Schwinden, M., Godfrey, J. D., Fox, R., Vawter, E. J., Zhang, B., Kissick, T. P., Patel, B., Mneimne, O., Humora, M., Papaioannou, C. G., Szymanski, W., Wong, M. K. Y., Chen, C. K., Heikes, J. E., DiMarco, J. D., Qiu, J., Deshpande, R. P., Gougoutas, J. Z. & Mueller, R. H. (2003). Org. Lett. 5, 3155-3158.]) or organoboranes (Collier et al. 2002[Collier, P. N., Campbell, A. D., Patel, I., Raynham, T. M. & Taylor, R. J. K. (2002). J. Org. Chem. 67, 1802-1815.]; Zhang et al., 2002[Zhang, J. Y., Xiong, C. Y., Wang, W., Ying, J. F. & Hruby, V. J. (2002). Org. Lett. 4, 4029-4032.]). Further asymmetric hydrogenation of their double bound allows non-proteinogenic α-amino acids and their derivatives to be obtained. Another important reaction of β-bromo-α,β-de­hydro­amino acid derivatives in drug research is their coupling cyclization in which oxazole derivatives are produced (Liu et al., 2014[Liu, B., Zhang, Y., Huang, G., Zhang, X., Niu, P., Wu, J., Yu, W. & Chang, J. (2014). Org. Biomol. Chem. 12, 3912-3923.]).

[Scheme 1]

2. Structural commentary

The mol­ecular structure of the title compound, (I)[link], is shown in Fig. 1[link]. The amino acids in the compound are linked trans to each other. The ω2 angle (C9—C10—N12—C13) is 175.79 (16)°, while ω3 (O5—C6—N8—C9) is 176.12 (15)°. There are no strong intra­molecular hydrogen bonds. The values of the φ2,3 and ψ2,3 angles corresponds to a non-helical conformation (Venkatachalam, 1968[Venkatachalam, C. M. (1968). Biopolymers, 6, 1425-1436.]). The dipeptide folds accordingly to the inter­molecular N—H⋯O-type hydrogen bonds. The β-bromo-de­hydro­alanine moiety shows typical geometrical tendencies. The C10—N12 bond is longer [1.366 (2) Å] than a typical bond in alanine, while the N12—C13 bond is shorter [1.406 (2) Å]. This effect is common for other de­hydro-residues (Ajó et al., 1979[Ajó, D., Granozzi, G., Tondello, E., Del Pra, A. & Zanotti, G. (1979). J. Chem. Soc. Perkin Trans. 2, pp. 927-929.]; Pieroni et al. 1975[Pieroni, O., Montagnoli, G., Fissi, A., Merlino, S. & Ciardelli, F. (1975). J. Am. Chem. Soc. 1, 6820-6826.]; Rzeszotarska et al., 2002[Rzeszotarska, B., Siodłak, D., Broda, M. A., Dybała, I. & Kozioł, A. E. (2002). J. Pept. Res. 59, 79-89.]; Jain & Chauhan, 1996[Jain, R. & Chauhan, V. S. (1996). Biopolymers, 40, 105-119.]). This indicates conjugation between the side chain of de­hydro­alanine and the peptide bond. The torsion angles around the Br(H)C=C grouping are −0.9 (3) and −174.28 (13)° (N12—C13—C14—Br15 and C16—C13—C14—Br15, respectively), meaning the stereochemistry about the bond is especially planar. This is consistent with the nature of an sp2-hybridized carbon on C13. The valance angles around the de­hydro­alanine group show some unusual values, especially N12—C13—C14 [124.27 (18)°], which may correspond to the presence of the bromine atom in the structure. The other angles are normal, as the backbone of the mol­ecule is folded to minimize steric repulsion. The Boc group features two short intra­molecular C—H⋯O contacts

[Figure 1]
Figure 1
The mol­ecular structure of Boc–Gly–(β-Br)(Z)ΔAla–OMe along with selected intra­molecular hydrogen bonds (dashed lines), drawn with 50% displacement ellipsoids.

3. Supra­molecular features

In the crystal, mol­ecules form two strong twin N—H⋯O (N8—H8A⋯O17i and N12—H12A⋯O7ii) and one weak accompanying C9—H9A⋯O11i hydrogen bonds (Fig. 1[link] and Table 1[link]), forming infinite sheets in the (001) plane [symmetry codes: (i) −x + 2, −y, −z + 1 and (ii) −x + 3, −y, −z + 1]. The sheets are connected to each other by weak C14—H14A⋯O11iii and C19—H19B⋯Br15iii hydrogen bonds and one Br⋯Briv [3.4149 (3) Å] halogen bond (Fig. 2[link]) of type I (Mukherjee & Desiraju, 2014[Mukherjee, A. & Desiraju, G. R. (2014). IUCrJ, 1, 49-60.]) [symmetry codes: (iii) −x + 2, −y + 1, −z + 1; (iv) −x + 3, −y + 1, −z + 1].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2A⋯O7 0.96 2.51 3.058 (2) 116
C3—H3A⋯O7 0.96 2.44 3.007 (3) 117
N8—H8A⋯O17i 0.86 2.19 3.018 (2) 162
C9—H9A⋯O11i 0.97 2.61 3.255 (2) 124
N12—H12A⋯O7ii 0.86 2.04 2.901 (2) 174
C14—H14A⋯O11iii 0.93 2.43 3.095 (2) 129
C19—H19B⋯Br15iii 0.96 3.14 3.668 (3) 117
Symmetry codes: (i) -x+2, -y, -z+1; (ii) -x+3, -y, -z+1; (iii) -x+2, -y+1, -z+1.
[Figure 2]
Figure 2
A packing diagram of (I)[link], viewed along the b axis, showing the inter­molecular hydrogen-bonding scheme (dashed lines).

4. Synthesis and crystallization

Boc–Gly–ΔAla and its methyl ester were prepared according to the methodology described by Makowski et al. (1985[Makowski, M., Rzeszotarska, B., Kubica, R. & Pietrzyński, G. (1985). Liebigs Ann. Chem. 5, 893-900.]) and Cossec et al. (2008[Cossec, B., Cosnier, F. & Burgart, M. (2008). Molecules, 13, 2394-2407.]). The β-bromo-vinyl derivative was obtained based on a procedure described previously (Bull et al., 2007[Bull, J. A., Balskus, E. P., Horan, R. A. J., Langner, M. & Ley, S. V. (2007). Chem. Eur. J. 13, 5515-5538.]). For this purpose 0.129 g (0.5 mM) of Boc–Gly–ΔAla–OMe was dissolved in 2.5 ml of di­chloro­methane and cooled to 193 K. Then, bromine 0.027 ml (0.5 mM) was added. The solution was stirred over 10 minutes followed by addition of tri­ethyl­amine 0.210 ml (1.5 mM). After 15 minutes, the mixture was quenched with 20 ml of saturated aqueous NaHCO3 and warmed to room temperature. The product was extracted by di­chloro­methane (3 × 15 ml). The organic layer was washed with brine (3 × 10 ml) and dried over anhydrous Na2SO4. Evaporation of the solvent at reduced pressure gave 0.119 g (0.35 mM) of crude product (70% yield). Recrystal­lization was performed from mixtures of diethyl ether/ethyl acetate­(2:1)/hexane solvents, yielding irregular colourless crystals. It is worth noting that in the case of our study, the formation of only the Z isomer was observed while in the preceding paper, the bromination of de­hydro­alanine-containing compound gave the E isomer. 1H NMR (400 MHz, DMSO) δ 1.38 (s, (s, 9H, C—H3 t-Boc), 3.67 (s, 3H, O—CH3), 3.69 (d, J = 6.2 Hz, 2H, C—H2 Gly), 7.05 (t, J = 6.2 Hz, 1H, N—HGly), 7.30 (s, 1H, C=CHBr), 9.63 (s, 1H, N—Hβ-Br–ΔAla). 13C NMR (101 MHz, DMSO) δ 28.21, 42.79, 52.54, 78.12, 113.26, 132.88, 155.80, 162.63, 168.80. Melting point = 386–388 K.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. All H atoms were positioned geometrically and treated as riding on their parent C or N atoms: for methyl groups, C—H = 0.96 Å and Uiso (H) = 1.5Ueq(C); for N atoms, N—H = 0.86 Å and Uiso (H) = 1.2Ueq(C); for secondary C atoms, C—H = 0.97 Å and Uiso (H) = 1.2Ueq(C), with no refinement of their parameters.

Table 2
Experimental details

Crystal data
Chemical formula C11H17BrN2O5
Mr 337.17
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 100
a, b, c (Å) 9.0431 (4), 9.3160 (4), 9.7540 (4)
α, β, γ (°) 83.381 (3), 75.420 (4), 64.863 (4)
V3) 719.92 (6)
Z 2
Radiation type Mo Kα
μ (mm−1) 2.87
Crystal size (mm) 0.30 × 0.25 × 0.20
 
Data collection
Diffractometer Oxford Diffraction Xcalibur
Absorption correction Multi-scan (CrysAlis RED; Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlisCCD and CrysAlisRED. Oxford Diffraction Ltd, Abingdon, England.])
Tmin, Tmax 0.655, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 4860, 2780, 2490
Rint 0.016
(sin θ/λ)max−1) 0.617
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.024, 0.066, 1.06
No. of reflections 2780
No. of parameters 172
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.53, −0.43
Computer programs: CrysAlis CCD and CrysAlis RED (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlisCCD and CrysAlisRED. Oxford Diffraction Ltd, Abingdon, England.]), SHELXS2014 and SHELXL2014 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Chemical context top

De­hydro­amino acids are analogues of amino acids characterized by the presence of an unsaturated doubled bound between the α- and β-carbon atoms in their structure. These compounds were found to be components of natural products (Bonauer et al., 2006), with lanti­biotics being especially important since they are an important class of natural bacteriocins produced by Gram-positive bacteria (Willey & van der Donk, 2007). The development of synthetic methods for the preparation of de­hydro­peptides allows researchers to search for their practical applications and to use them as substrates for the production of peptidomimetics. One of the inter­esting classes of such mimetics are β-bromo-de­hydro­amino acids and their derivatives, which are usually obtained by radical halogenation of de­hydro­amino acids using N-bromo­succinimide (NBS). This reaction proceeds in two steps, namely by halogenation of de­hydro­amino acids, which gives α-bromo-imines, followed by tautomerization to the desired products upon treatment with an amine (Coleman & Carpenter, 1993; Zhang et al., 2002). β-Bromo-de­hydro­amino acid derivatives are useful substrates in coupling reactions with alkynes (Singh et al., 2003) or organoboranes (Collier et al. 2002; Zhang et al., 2002). Further asymmetric hydrogenation of their double bound allows non-proteinogenic α-amino acids and their derivatives to be obtained. Another important reaction of β-bromo-α,β-de­hydro­amino acid derivatives in drug research is their coupling cyclization in which oxazole derivatives are produced (Liu et al., 2014).

Structural commentary top

The molecular structure of the title compound, (I), is shown in Fig. 1. The amino acids in the compound are linked trans to each other. The ω2 angle (C9—C10—N12—C13) is 175.79 (16)°, while ω3 (O5—C6—N8—C9) is 176.12 (15)°. There are no strong intra­molecular hydrogen bonds. The values of the ϕ2,3 and ψ2,3 angles corresponds to a non-helical conformation (Venkatachalam, 1968). The dipeptide folds accordingly to the inter­molecular N—H···O-type hydrogen bonds. The β-bromo-de­hydro­alanine moiety shows typical geometrical tendencies. The C10—N12 bond is longer [1.366 (2) Å] than a typical bond in alanine, while the N12—C13 bond is shorter [1.406 (2) Å]. This effect is common for other de­hydro-residues (Ajó et al., 1979; Pieroni et al. 1975; Rzeszotarska et al., 2002; Jain & Chauhan, 1996). This indicates conjugation between the side chain of de­hydro­alanine and the peptide bond. The torsion angles around the Br(H)C C grouping are -0.9 (3) and -174.28 (13)° (N12—C13—C14—Br15 and C16—C13—C14—Br15, respectively), meaning the stereochemistry about the bond is especially planar. This is consistent with the nature of an sp2-hybridized carbon on C13. The valance angles around the de­hydro­alanine group show some unusual values, especially N12—C13—C14 [124.27 (18)°], which may correspond to the presence of the bromine atom in the structure. The other angles are normal, as the backbone of the molecule is folded to minimize steric repulsion. The Boc group features two short intra­molecular C—H···O contacts

Supra­molecular features top

In the crystal, molecules form two strong twin N—H···O (N8—H8A···O17i and N12—H12A···O7ii) and one weak accompanying C9—H9A···O11i hydrogen bonds (Fig. 1), forming infinite sheets in the (001) plane [symmetry codes: (i) -x + 2, -y, -z + 1 and (ii) -x + 3, -y, -z + 1]. The sheets are connected to each other by weak C14—H14A···O11iii and C19—H19B···Br15iii hydrogen bonds and one Br···Briv [3.4149 (3) Å] halogen bond of type I (Mukherjee & Desiraju, 2014) [symmetry codes: (iii) -x + 2, -y + 1, -z + 1; (iv) -x + 3, -y + 1, -z + 1].

Synthesis and crystallization top

Boc–Gly–ΔAla and its methyl ester were prepared according to the methodology described by Makowski et al. (1985) and Cossec et al. (2008). The β-bromo-vinyl derivative was obtained based on a procedure described previously (Bull et al., 2007). For this purpose 0.129 g (0.5 mM) of Boc–Gly–ΔAla–OMe was dissolved in 2.5 ml of di­chloro­methane and cooled to 193 K. Then, bromine 0.027 ml (0.5 mM) was added. The solution was stirred over 10 minutes followed by addition of tri­ethyl­amine 0.210 ml (1.5 mM). After 15 minutes, the mixture was quenched with 20 ml of saturated aqueous NaHCO3 and warmed to room temperature. The product was extracted by di­chloro­methane (3 × 15 ml). The organic layer was washed with brine (3 × 10 ml) and dried over anhydrous Na2SO4. Evaporation of the solvent at reduced pressure gave 0.119 g (0.35 mM) of crude product (70% yield). Recrystallization was performed from mixtures of di­ethyl ether/ethyl acetate­(2:1)/hexane solvents, yielding irregular colourless crystals. It is worth noting that in the case of our study, the formation of only the Z isomer was observed while in the preceding paper, the bromination of de­hydro­alanine-containing compound gave the E isomer. 1H NMR (400 MHz, DMSO) δ 1.38 (s, (s, 9H, C—H3 t-Boc), 3.67 (s, 3H, O—CH3), 3.69 (d, J = 6.2 Hz, 2H, C—H2 Gly), 7.05 (t, J = 6.2 Hz, 1H, N—HGly), 7.30 (s, 1H, CCHBr), 9.63 (s, 1H, N—Hβ-Br–ΔAla). 13C NMR (101 MHz, DMSO) δ 28.21, 42.79, 52.54, 78.12, 113.26, 132.88, 155.80, 162.63, 168.80. Melting point = 386–388 K.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 2. All H atoms were positioned geometrically and treated as riding on their parent C or N atoms: for methyl groups, C—H = 0.96 Å and Uiso (H) = 1.5Ueq(C); for N atoms, N—H = 0.86 Å and Uiso (H) = 1.2Ueq(C); for secondary C atoms, C—H = 0.97 Å and Uiso (H) = 1.2Ueq(C), with no refinement of their parameters.

Related literature top

For general background to the use of dehydroaminoacids, see: review Bonauer et al., 2006; Coleman & Carpenter, 1993; Zhang et al., 2002; Singh et al., 2003; For a related structures, see: Ajó et al., 1979; Pieroni et al. 1975; Rzeszotarska et al., 2002 Jain & Chauhan, 1996.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2010); cell refinement: CrysAlis RED (Oxford Diffraction, 2010); data reduction: CrysAlis RED (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2008).

Figures top
Fig. 1. The molecular structure of Boc–Gly–(β-Br)(Z)ΔAla–OMe along with selected intramolecular hydrogen bonds (dashed lines), drawn with 50% displacement ellipsoids.

Fig. 2. A packing diagram of (I), viewed along the b axis, showing the intermolecular hydrogen-bonding scheme (dashed lines).
N-(tert-Butoxycarbonyl)glycyl-(Z)-β-bromodehydroalanine methyl ester top
Crystal data top
C11H17BrN2O5Z = 2
Mr = 337.17F(000) = 344
Triclinic, P1Dx = 1.555 Mg m3
a = 9.0431 (4) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.3160 (4) ÅCell parameters from 4860 reflections
c = 9.7540 (4) Åθ = 3.2–26.0°
α = 83.381 (3)°µ = 2.87 mm1
β = 75.420 (4)°T = 100 K
γ = 64.863 (4)°Irregular, colourless
V = 719.92 (6) Å30.30 × 0.25 × 0.20 mm
Data collection top
Oxford Diffraction Xcalibur
diffractometer
2780 independent reflections
Radiation source: fine-focus sealed tube2490 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.016
Detector resolution: 1024 pixels mm-1θmax = 26.0°, θmin = 3.2°
ω scanh = 811
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2010)
k = 1011
Tmin = 0.655, Tmax = 1.000l = 1212
4860 measured reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.024H-atom parameters constrained
wR(F2) = 0.066 w = 1/[σ2(Fo2) + (0.0444P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
2780 reflectionsΔρmax = 0.53 e Å3
172 parametersΔρmin = 0.43 e Å3
Crystal data top
C11H17BrN2O5γ = 64.863 (4)°
Mr = 337.17V = 719.92 (6) Å3
Triclinic, P1Z = 2
a = 9.0431 (4) ÅMo Kα radiation
b = 9.3160 (4) ŵ = 2.87 mm1
c = 9.7540 (4) ÅT = 100 K
α = 83.381 (3)°0.30 × 0.25 × 0.20 mm
β = 75.420 (4)°
Data collection top
Oxford Diffraction Xcalibur
diffractometer
2780 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2010)
2490 reflections with I > 2σ(I)
Tmin = 0.655, Tmax = 1.000Rint = 0.016
4860 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0240 restraints
wR(F2) = 0.066H-atom parameters constrained
S = 1.06Δρmax = 0.53 e Å3
2780 reflectionsΔρmin = 0.43 e Å3
172 parameters
Special details top

Experimental. CrysAlis RED, Oxford Diffraction Ltd., Version 1.171.33.57 (release 26-01-2010 CrysAlis171 .NET) (compiled Jan 26 2010,14:36:55) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
C11.2957 (3)0.1495 (2)0.9892 (2)0.0186 (4)
C21.4783 (3)0.2662 (3)0.9655 (2)0.0248 (5)
H2A1.54550.22430.89520.037*
H2B1.49040.36510.93360.037*
H2C1.51460.28301.05270.037*
C31.2675 (3)0.0136 (3)1.0284 (2)0.0291 (5)
H3A1.33740.05180.95720.044*
H3B1.29520.00831.11820.044*
H3C1.15200.08441.03480.044*
C41.1870 (3)0.2140 (3)1.1000 (2)0.0313 (5)
H4A1.07200.13871.11460.047*
H4B1.22280.23161.18750.047*
H4C1.19750.31221.06790.047*
O51.23184 (17)0.14194 (16)0.86239 (14)0.0186 (3)
C61.2959 (2)0.0915 (2)0.7363 (2)0.0144 (4)
O71.40332 (16)0.03851 (15)0.71486 (14)0.0161 (3)
N81.2267 (2)0.10813 (19)0.63638 (17)0.0155 (3)
H8A1.15730.15220.65780.019*
C91.2670 (2)0.0531 (2)0.49289 (19)0.0149 (4)
H9A1.25290.11570.42830.018*
H9B1.38350.06850.46880.018*
C101.1567 (2)0.1209 (2)0.47430 (19)0.0143 (4)
O111.00831 (16)0.18140 (15)0.53245 (14)0.0179 (3)
N121.23628 (19)0.20273 (18)0.38410 (17)0.0146 (3)
H12A1.34210.15560.34840.017*
C131.1490 (2)0.3623 (2)0.34831 (19)0.0136 (4)
C141.1990 (2)0.4770 (2)0.3536 (2)0.0164 (4)
H14A1.13410.57920.32660.020*
Br151.39326 (2)0.44202 (2)0.41252 (2)0.02292 (9)
C161.0010 (2)0.4006 (2)0.2866 (2)0.0163 (4)
O170.97138 (18)0.30286 (17)0.24167 (15)0.0210 (3)
O180.90913 (18)0.55685 (16)0.28281 (16)0.0239 (3)
C190.7741 (3)0.6065 (3)0.2098 (3)0.0324 (5)
H19A0.71550.71990.21290.049*
H19B0.69790.55940.25520.049*
H19C0.81930.57310.11300.049*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0226 (10)0.0227 (10)0.0121 (9)0.0104 (9)0.0065 (8)0.0034 (8)
C20.0266 (11)0.0256 (11)0.0202 (11)0.0075 (9)0.0108 (9)0.0066 (9)
C30.0397 (14)0.0268 (12)0.0204 (11)0.0129 (10)0.0070 (10)0.0014 (9)
C40.0369 (13)0.0432 (14)0.0172 (11)0.0222 (11)0.0058 (9)0.0088 (10)
O50.0202 (7)0.0248 (7)0.0141 (7)0.0133 (6)0.0061 (6)0.0077 (6)
C60.0131 (9)0.0102 (9)0.0158 (10)0.0021 (7)0.0029 (7)0.0040 (7)
O70.0173 (7)0.0166 (7)0.0174 (7)0.0100 (6)0.0049 (5)0.0028 (5)
N80.0169 (8)0.0164 (8)0.0167 (8)0.0105 (7)0.0063 (7)0.0074 (7)
C90.0175 (9)0.0136 (9)0.0136 (9)0.0069 (8)0.0042 (7)0.0038 (7)
C100.0187 (10)0.0152 (9)0.0126 (9)0.0091 (8)0.0065 (8)0.0017 (7)
O110.0153 (7)0.0149 (7)0.0198 (7)0.0054 (6)0.0009 (6)0.0035 (5)
N120.0120 (8)0.0130 (8)0.0169 (8)0.0050 (6)0.0019 (6)0.0034 (6)
C130.0147 (9)0.0143 (9)0.0115 (9)0.0069 (8)0.0019 (7)0.0031 (7)
C140.0137 (9)0.0164 (9)0.0191 (10)0.0061 (8)0.0049 (8)0.0021 (8)
Br150.01942 (12)0.02164 (12)0.03230 (14)0.01022 (9)0.00996 (9)0.00138 (8)
C160.0181 (10)0.0171 (10)0.0130 (9)0.0083 (8)0.0032 (8)0.0060 (8)
O170.0250 (8)0.0209 (7)0.0224 (8)0.0129 (6)0.0093 (6)0.0028 (6)
O180.0222 (7)0.0168 (7)0.0346 (9)0.0061 (6)0.0164 (6)0.0071 (6)
C190.0287 (12)0.0290 (12)0.0417 (14)0.0095 (10)0.0229 (11)0.0157 (10)
Geometric parameters (Å, º) top
C1—O51.474 (2)C9—C101.518 (2)
C1—C31.508 (3)C9—H9A0.9700
C1—C21.517 (3)C9—H9B0.9700
C1—C41.521 (3)C10—O111.220 (2)
C2—H2A0.9600C10—N121.366 (2)
C2—H2B0.9600N12—C131.406 (2)
C2—H2C0.9600N12—H12A0.8600
C3—H3A0.9600C13—C141.335 (3)
C3—H3B0.9600C13—C161.494 (3)
C3—H3C0.9600C14—Br151.8715 (19)
C4—H4A0.9600C14—H14A0.9300
C4—H4B0.9600C16—O171.204 (2)
C4—H4C0.9600C16—O181.337 (2)
O5—C61.345 (2)O18—C191.447 (2)
C6—O71.229 (2)C19—H19A0.9600
C6—N81.338 (2)C19—H19B0.9600
N8—C91.446 (2)C19—H19C0.9600
N8—H8A0.8600
O5—C1—C3110.80 (16)C9—N8—H8A119.5
O5—C1—C2109.75 (16)N8—C9—C10111.87 (15)
C3—C1—C2112.96 (18)N8—C9—H9A109.2
O5—C1—C4101.56 (15)C10—C9—H9A109.2
C3—C1—C4110.90 (18)N8—C9—H9B109.2
C2—C1—C4110.29 (18)C10—C9—H9B109.2
C1—C2—H2A109.5H9A—C9—H9B107.9
C1—C2—H2B109.5O11—C10—N12122.87 (17)
H2A—C2—H2B109.5O11—C10—C9122.69 (16)
C1—C2—H2C109.5N12—C10—C9114.41 (16)
H2A—C2—H2C109.5C10—N12—C13121.43 (16)
H2B—C2—H2C109.5C10—N12—H12A119.3
C1—C3—H3A109.5C13—N12—H12A119.3
C1—C3—H3B109.5C14—C13—N12124.27 (18)
H3A—C3—H3B109.5C14—C13—C16118.50 (17)
C1—C3—H3C109.5N12—C13—C16116.92 (16)
H3A—C3—H3C109.5C13—C14—Br15123.17 (15)
H3B—C3—H3C109.5C13—C14—H14A118.4
C1—C4—H4A109.5Br15—C14—H14A118.4
C1—C4—H4B109.5O17—C16—O18124.26 (18)
H4A—C4—H4B109.5O17—C16—C13124.08 (18)
C1—C4—H4C109.5O18—C16—C13111.61 (16)
H4A—C4—H4C109.5C16—O18—C19115.57 (16)
H4B—C4—H4C109.5O18—C19—H19A109.5
C6—O5—C1121.71 (14)O18—C19—H19B109.5
O7—C6—N8124.52 (17)H19A—C19—H19B109.5
O7—C6—O5125.30 (17)O18—C19—H19C109.5
N8—C6—O5110.18 (16)H19A—C19—H19C109.5
C6—N8—C9120.96 (15)H19B—C19—H19C109.5
C6—N8—H8A119.5
C3—C1—O5—C662.8 (2)C9—C10—N12—C13175.79 (16)
C2—C1—O5—C662.6 (2)C10—N12—C13—C14130.6 (2)
C4—C1—O5—C6179.35 (17)C10—N12—C13—C1655.9 (2)
C1—O5—C6—O74.7 (3)N12—C13—C14—Br150.9 (3)
C1—O5—C6—N8174.87 (15)C16—C13—C14—Br15174.28 (13)
O7—C6—N8—C94.3 (3)C14—C13—C16—O17159.29 (19)
O5—C6—N8—C9176.12 (15)N12—C13—C16—O1714.6 (3)
C6—N8—C9—C1086.1 (2)C14—C13—C16—O1818.4 (2)
N8—C9—C10—O1138.0 (3)N12—C13—C16—O18167.72 (16)
N8—C9—C10—N12143.70 (16)O17—C16—O18—C194.6 (3)
O11—C10—N12—C132.5 (3)C13—C16—O18—C19173.12 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2A···O70.962.513.058 (2)116
C3—H3A···O70.962.443.007 (3)117
N8—H8A···O17i0.862.193.018 (2)162
C9—H9A···O11i0.972.613.255 (2)124
N12—H12A···O7ii0.862.042.901 (2)174
C14—H14A···O11iii0.932.433.095 (2)129
C19—H19B···Br15iii0.963.143.668 (3)117
Symmetry codes: (i) x+2, y, z+1; (ii) x+3, y, z+1; (iii) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2A···O70.962.513.058 (2)116
C3—H3A···O70.962.443.007 (3)117
N8—H8A···O17i0.862.193.018 (2)162
C9—H9A···O11i0.972.613.255 (2)124
N12—H12A···O7ii0.862.042.901 (2)174
C14—H14A···O11iii0.932.433.095 (2)129
C19—H19B···Br15iii0.963.143.668 (3)117
Symmetry codes: (i) x+2, y, z+1; (ii) x+3, y, z+1; (iii) x+2, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC11H17BrN2O5
Mr337.17
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)9.0431 (4), 9.3160 (4), 9.7540 (4)
α, β, γ (°)83.381 (3), 75.420 (4), 64.863 (4)
V3)719.92 (6)
Z2
Radiation typeMo Kα
µ (mm1)2.87
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerOxford Diffraction Xcalibur
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2010)
Tmin, Tmax0.655, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
4860, 2780, 2490
Rint0.016
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.024, 0.066, 1.06
No. of reflections2780
No. of parameters172
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.53, 0.43

Computer programs: CrysAlis CCD (Oxford Diffraction, 2010), CrysAlis RED (Oxford Diffraction, 2010), SHELXS2014 (Sheldrick, 2008), SHELXL2014 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

This study was supported by the Wrocław Research Centre EIT+ under the project Biotechnologies and advanced medical technologies – BioMed (POIG.01.01.02–02-003/08) financed from the European Regional Development Fund (Operational Programme Innovative Economy, 1.1.2). PL is the recipient of a PhD fellowships from a project funded by the European Social Fund.

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