research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 10| October 2016| Pages 1429-1433
https://doi.org/10.1107/S2056989016014420

Crystal structures of the two epimers from the unusual thermal C6-epimerization of 5-oxo-1,2,3,5,5a,6,7,9b-octa­hydro-7,9a-ep­­oxy­pyrrolo­[2,1-a]iso­indole-6-carb­­oxy­lic acid, 5a(RS),6(SR),7(RS),9a(SR),9b(SR) and 5a(RS),6(RS),7(RS),9a(SR),9b(SR)

CROSSMARK_Color_square_no_text.svg
Dmitry S. Poplevin,a Fedor I. Zubkov,a Pavel V. Dorovatovskii,b Yan V. Zubavichusb and Victor N. Khrustalevc,d*

aOrganic Chemistry Department, Peoples' Friendship University of Russia (RUDN University), 6 Miklukho-Maklay St., Moscow 117198, Russian Federation, bNational Research Centre "Kurchatov Institute", 1 Acad. Kurchatov Sq., Moscow 123182, Russian Federation, cInorganic Chemistry Department, Peoples' Friendship University of Russia (RUDN University), 6 Miklukho-Maklay St., Moscow 117198, Russian Federation, and dX-Ray Structural Centre, A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov St., B–334, Moscow 119991, Russian Federation
*Correspondence e-mail: vnkhrustalev@gmail.com

Edited by G. Smith, Queensland University of Technology, Australia (Received 12 August 2016; accepted 11 September 2016; online 16 September 2016)

The isomeric title compounds, C12H13NO4 (Ia) and C12H13NO4 (IIa), the products of an usual thermal C6-epimerization of 5-oxo-1,2,3,5,5a,6,7,9b-octa­hydro-7,9a-ep­oxy­pyrrolo­[2,1-a]iso­indole-6-carb­oxy­lic acid, represent the two different diastereomers and have very similar mol­ecular geometries. The mol­ecules of both compounds comprise a fused tetra­cyclic system containing four five-membered rings (pyrrolidine, pyrrolidinone, di­hydro­furan and tetra­hydro­furan), all of which adopt the usual envelope conformations. The dihedral angle between the basal planes of the pyrrolidine and pyrrolidinone rings are 14.3 (2) and 16.50 (11)°, respectively, for (Ia) and (IIa). The nitro­gen atom has a slightly pyramidalized geometry [bond-angle sum = 355.9 and 355.3°, for (Ia) and (IIa)], respectively. In the crystal of (Ia), mol­ecules form zigzag-like hydrogen-bonded chains along [010] through strong O—H⋯O hydrogen bonds and are further linked by weak C—H⋯O hydrogen bonds into complex two-tier layers parallel to (100). Unlike (Ia), the crystal of (IIa) contains centrosymmetric cyclic hydrogen-bonded dimers [graph set R22(14)], formed through strong O—H⋯O hydrogen bonds and are further linked by weak C—H⋯O hydrogen bonds into ribbons extending across [101].

CCDC references: 1503860; 1503859

Similar articles

1. Chemical context

The intra­molecular Diels–Alder furan (IMDAF) reaction between α,β-unsaturated acid anhydrides and hydrogenated heterocycles, containing a furfuryl­amine moiety, has been studied for a long time (see, for example, Parker & Adamchuk, 1978[Parker, K. A. & Adamchuk, M. R. (1978). Tetrahedron Lett. 19, 1689-1692.]; Blokzijl et al., 1991[Blokzijl, W., Blandamer, M. J. & Engberts, J. (1991). J. Am. Chem. Soc. 113, 4241-4246.]; Varlamov et al., 2006[Varlamov, A. V., Boltukhina, E. V., Zubkov, F. I., Nikitina, E. V. & Turchin, K. F. (2006). J. Heterocycl. Chem. 43, 1479-1495.]; Groenendaal et al., 2008[Groenendaal, B., Ruijter, E., de Kanter, F., Lutz, M., Spek, A. L. & Orru, R. V. (2008). Org. Biomol. Chem. 6, 3158-3165.]; Nakamura et al., 2011[Nakamura, M., Takahashi, I., Yamada, S., Dobashi, Y. & Kitagawa, O. (2011). Tetrahedron Lett. 52, 53-55.]; Zubkov et al., 2011[Zubkov, F. I., Zaytsev, V. P., Nikitina, E. V., Khrustalev, V. N., Gozun, S. V., Boltukhina, E. V. & Varlamov, A. V. (2011). Tetrahedron, 67, 9148-9163.], 2012[Zubkov, F. I., Airiyan, I. K., Ershova, J. D., Galeev, T. R., Zaytsev, V. P., Nikitina, E. V. & Varlamov, A. V. (2012). RSC Adv. 2, 4103-4109.], 2014[Zubkov, F. I., Nikitina, E. V., Galeev, T. R., Zaytsev, V. P., Khrustalev, V. N., Novikov, R. A., Orlova, D. N. & Varlamov, A. V. (2014). Tetrahedron, 70, 1659-1690.]; Toze et al., 2015[Toze, F. A. A., Poplevin, D. S., Zubkov, F. I., Nikitina, E. V., Porras, C. & Khrustalev, V. N. (2015). Acta Cryst. E71, o729-o730.]) and used for diastereospecific synthesis of diverse fused-ring systems. It is arguable that the pathway with a simultaneous controlled formation of four or five new stereogenic centers is the best approach to ep­oxy­iso­indoles and affords target adducts under mild conditions with satisfactory yields. However, the simplest 2-furyl aza­heterocycles (azetidine, pyrrolidine, piperidine, perhydro­azepine) have not yet been studied in this reaction. One of the goals of our work is to fill the gap. Here we report on the utilization of 2-furyl pyrrolidine as an initial reagent in the IMDAF reaction.

[Scheme 1]

The inter­action between 2-furyl pyrrolidine and maleic anhydride at room temperature leads to the mixture of cyclic (Ia) and open-chain (Ib) tautomers, the crystallization of which results in the cyclic form (Ia) only (Fig. 1[link]). In contrast, the same reaction at 413 K leads to the maleic amide fragment isomerization and affords a mixture of the adduct (IIa) and the amide (IIb) (Fig. 2[link]). Similarly, the mixture crystallization gives rise the cyclic tautomer (IIa) only. The crystal structures of both (Ia) and (IIa) using synchrotron X-ray diffraction data have been determined and are reported herein.

[Figure 1]
Figure 1
Reaction of 2-furyl pyrrolidine and maleic anhydride at room temperature.
[Figure 2]
Figure 2
Reaction of 2-furyl pyrrolidine and maleic anhydride at 413 K.

2. Structural commentary

Compounds (Ia) and (IIa) represent two different diastereo­mers of 5-oxo-1,2,3,5,5a,6,7,9b-octa­hydro-7,9a-ep­oxy­pyrrolo[2,1-a]iso­indole-6-carb­oxy­lic acid and have very similar mol­ecular geometries (Figs. 3[link], 4[link]). The mol­ecules of (Ia) and (IIa) each comprise a fused tetra­cyclic system containing four five-membered rings (pyrrolidine, pyrrolidinone, di­hydro­furan and tetra­hydro­furan), all of which adopt the usual envelope conformations. The dihedral angles between the basal planes of the pyrrolidine and pyrrolidinone rings are 14.3 (2) and 16.50 (11)°, respectively, for (Ia) and (IIa). The nitro­gen N4 atom has a slightly pyramidalized geometry [sum of the bond angles = 355.9 and 355.3°, respectively, for (Ia) and (IIa)]. The bond lengths and angles in both epimers are in good agreement with those observed in a related structure (Lu et al., 2013[Lu, Q., Huang, X., Song, G., Sun, C.-M., Jasinski, J. P., Keeley, A. C. & Zhang, W. (2013). ACS Comb. Sci. 15, 350-355.]).

[Figure 3]
Figure 3
Mol­ecular structure and atom-numbering scheme for epimer (Ia). Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as small spheres of arbitrary radius.
[Figure 4]
Figure 4
Mol­ecular structure and atom-numbering scheme for epimer (IIa). Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as small spheres of arbitrary radius.

The mol­ecules possess five asymmetric centers at the C5, C6, C7, C9a and C9b carbon atoms. The crystals of (Ia) and (IIa) are racemic and consist of enanti­omeric pairs with the following relative configurations of the centers: 5a(RS),6(SR),7(RS),9a(SR),9b(SR) and 5a(RS),6(RS),7(RS),9a(SR),9b(SR)

3. Supra­molecular features

Although the similarity of the mol­ecular geometries might lead to similar packing motifs, this is not found in the case of (Ia) and (IIa). The inter­molecular inter­actions, namely strong O—H⋯O and weak C—H⋯O hydrogen bonding, combined in a different way, give rise to different packing networks. In the crystal of (Ia), mol­ecules form zigzag-like hydrogen-bonded chains extending along [010] through strong O12—H12⋯O5i hydrogen bonds, which are further linked by weak C5A—H5A⋯O12ii hydrogen bonds into complex two-tier layers lying parallel to (100) (Table 1[link], Fig. 5[link]).

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

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O12—H12⋯O5i 0.90 (3) 1.75 (3) 2.613 (2) 157 (3)
C5A—H5A⋯O12ii 1.00 2.51 3.234 (3) 129
Symmetry codes: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+1.
[Figure 5]
Figure 5
Crystal structure of (Ia) showing the two-tier layers parallel to (100). Dashed lines indicate the inter­molecular O—H⋯O and C—H⋯O hydrogen bonds.

However, unlike (Ia), the crystal of (IIa) contains centrosymmetric hydrogen-bonded cyclic dimers [graph set R22(14), formed through two strong O12—H12⋯O5i hydrogen bonds (Table 2[link], Fig. 6[link]). The dimers are further linked by weak C9—H9⋯O11ii hydrogen bonds into ribbons extending across [101] (Table 2[link], Figs. 6[link] and 7[link]).

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

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O12—H12⋯O5i 0.92 1.70 2.607 (2) 165
C9—H9⋯O11ii 0.95 2.42 3.362 (3) 172
Symmetry codes: (i) -x+2, -y+1, -z+1; (ii) -x+1, -y+1, -z.
[Figure 6]
Figure 6
The hydrogen-bonded chains of (IIa). Dashed lines indicate the inter­molecular O—H⋯O and C—H⋯O hydrogen bonds.
[Figure 7]
Figure 7
Crystal structure of (IIa) along [101]. Dashed lines indicate the inter­molecular O—H⋯O and C—H⋯O hydrogen bonds.

4. Synthesis and crystallization

The initial 2-furyl pyrrolidine was synthesized according to the procedure described previously (Acher et al., 1981[Asher, V., Becu, C., Anteunis, M. J. O. & Callens, R. (1981). Tetrahedron Lett. 22, 141-144.]; Shono et al., 1981[Shono, T., Matsumura, Y., Tsubata, K. O. & Takata, J. (1981). Chem. Lett. 10, 1121-1124.]; Nikolic & Beak, 1997[Nikolic, N. A. & Beak, P. (1997). Org. Synth. 74, 23-32.]).

Synthesis of (Ia). A mixture of the initial 2-furyl pyrrolidine (0.30 g, 2.2 mmol) and maleic anhydride (0.23 g, 2.3 mmol) in di­chloro­methane (6 mL) was stirred for 5 h at r.t. [monitoring by TLC until disappearance of the starting compound spot, eluent–EtOAc: hexane (1:3), Sorbfil]. On completion of the reaction, the solvent was evaporated. The isomer (Ia) was isolated as fine needles by slow recrystallization of the residue from a mixture of EtOAc–EtOH. Yield 39%: m.p. = 413–414 K. IR (KBr), ν (cm−1): 1734, 1654. 1H NMR (CDCl3, 400 MHz, 300 K): δ = 1.98–1.69 (m, 4H, H1a, H1b, H2a, H2b), 2.42 (d, 1H, H6, J6,5a = 9.1), 2.94–2.88 (m, 2H, H3a, H3b), 3.10 (d, 1H, H5a, J5a,6 = 9.1), 4.41 (t, 1H, H9b, J9b,1a = 7.5, J9b,1 b = 7.5), 4.97 (d, 1H, H7, J7,8 = 1.6), 6.44 (dd, 1H, H8, J8,9 = 5.5, J8,7 = 1.6), 6.54 (d, 1H, H9, J9,8 = 5.5). 13C NMR (CDCl3, 100 MHz, 300 K): δ = 23.5, 26.2, 41.9 (C1, C2, C3), 46.9, 53.8 (C6, C5a), 60.0 (C9b), 80.5 (C7), 93.5 (C9a), 133.9 (C9), 137.1 (C8), 171.7, 173.2 (NCO, COOH). EI–MS (70 eV), m/z (rel. intensity): 235 (22), 217 (91), 137 (41), 136 (100), 108 (39), 80 (45), 70 (32), 54 (38), 45 (29), 42 (25).

Synthesis of (IIa). A mixture of the initial 2-furyl pyrrolidine (0.3 g, 2.2 mmol) and maleic anhydride (0.23 g, 2.3 mmol) in o-xylene (6 mL) was heated at reflux for 3 h. At the end of the reaction, the solvent was evaporated. The isomer (IIa) was isolated as fine needles by slow recrystallization of the residue from a mixture of EtOAc–EtOH. Yield: 0.33 45%; m.p. = 414–416 K. IR (KBr), ν (cm−1): 1738, 1658. 1H NMR (CDCl3, 400 MHz, 300 K): δ = 1.82–1.64 (m, 4H, H1a, H1b, H2a, H2b), 3.02 (d, 1H, H5a, J5a,6 = 3.4), 3.17 (dd, 1H, H6, J6,5a = 3.4, J6,5a = 3.4), 3.36–3.32 (m, 2H, H3a, H3b), 4.52 (t, 1H, H9b, J9b,1a = 7.6, J9b,1b = 7.6), 5.20 (dd, 1H, H7, J7,8 = 1.6, J7,6 = 4.8), 6.34 (dd, 1H, H8, J8,9 = 5.8, J8,7 = 1.6), 6.66 (d, 1H, H9, J9,8 = 5.8). 13C NMR (CDCl3, 100 MHz, 300 K): δ = 23.5, 26.2, 42.1 (C1, C2, C3), 47.0, 55.1 (C6, C5a), 61.0 (C9b), 79.2 (C7), 93.5 (C9a), 133.9 (C8), 135.2 (C9), 171.7, 173.2 (NCO, COOH). EI–MS (70 eV), m/z (rel. intensity): 235 (22), 217 (91), 137 (41), 136 (100), 108 (39), 80 (45), 70 (32), 54 (38), 45 (29), 42 (25).

5. Refinement

Crystal data, data collection and refinement details are summarized in Table 3[link]. X-ray diffraction studies were carried out on the `Belok' beamline (λ = 0.96990 Å) of the National Research Center "Kurchatov Institute" (Moscow, Russian Federation) using a MAR CCD detector.

Table 3
Experimental details

  (Ia) (IIa)
Crystal data
Chemical formula C12H13NO4 C12H13NO4
Mr 235.23 235.23
Crystal system, space group Monoclinic, P21/c Triclinic, P[\overline{1}]
Temperature (K) 100 100
a, b, c (Å) 11.045 (2), 9.2023 (18), 11.062 (2) 8.4700 (17), 8.5100 (17), 8.5900 (17)
α, β, γ (°) 90, 100.91 (3), 90 94.04 (3), 111.12 (3), 105.17 (3)
V (Å3) 1104.1 (4) 548.0 (2)
Z 4 2
Radiation type Synchrotron, λ = 0.96990 Å Synchrotron, λ = 0.96990 Å
μ (mm−1) 0.23 0.23
Crystal size (mm) 0.20 × 0.15 × 0.15 0.15 × 0.10 × 0.10
 
Data collection
Diffractometer MAR CCD MAR CCD
Absorption correction Multi-scan (SCALA; Evans, 2006[Evans, P. (2006). Acta Cryst. D62, 72-82.]) Multi-scan (SCALA; Evans, 2006[Evans, P. (2006). Acta Cryst. D62, 72-82.])
Tmin, Tmax 0.950, 0.960 0.960, 0.969
No. of measured, independent and observed [I > 2σ(I)] reflections 12183, 2329, 1864 7090, 2104, 1402
Rint 0.085 0.061
(sin θ/λ)max (Å−1) 0.641 0.637
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.072, 0.189, 1.02 0.099, 0.240, 0.93
No. of reflections 2329 2104
No. of parameters 158 155
H-atom treatment H atoms treated by a mixture of independent and constrained refinement H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.43, −0.43 0.45, −0.36
Computer programs: Automar (MarXperts, 2015[MarXperts. (2015). Automar. MarXperts GmbH, D-22844 Norderstedt, Germany.]), iMOSFLM (Battye et al., 2011[Battye, T. G. G., Kontogiannis, L., Johnson, O., Powell, H. R. & Leslie, A. G. W. (2011). Acta Cryst. D67, 271-281.]), SHELXS97 and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]).

The hydrogen atoms of the hydroxyl groups were localized in the difference-Fourier maps and refined in an isotropic approximation with fixed displacement parameters [Uiso(H) = 1.5Ueq(O)] [for (Ia)] or included in the refinement with fixed positional (riding model) and isotropic displacement parameters [Uiso(H) = 1.5Ueq(O)] [for (IIa)]. Other hydrogen atoms were placed in calculated positions with C—H = 0.95–1.00 Å and refined in the riding model with fixed isotropic displacement parameters [Uiso(H) = 1.2Ueq(C)].

The insufficient data completeness of 94.1% in the case of (IIa) is the result of the low (triclinic) crystal symmetry, making it very difficult to obtain good data completeness using the φ scan mode only (`Belok' beamline limitation), even though we have used the two different crystal orientations.

Supporting information

CCDC references: 1503860; 1503859

Crystal structure: contains datablocks global, Ia, IIa. DOI: https://doi.org/10.1107/S2056989016014420/zs2368sup1.cif

Structure factors: contains datablock Ia. DOI: https://doi.org/10.1107/S2056989016014420/zs2368Iasup2.hkl

Structure factors: contains datablock IIa. DOI: https://doi.org/10.1107/S2056989016014420/zs2368IIasup3.hkl

checkCIF report


Computing details top

For both compounds, data collection: Automar (MarXperts, 2015); cell refinement: iMOSFLM (Battye et al., 2011); data reduction: iMOSFLM (Battye et al., 2011); program(s) used to solve structure: SHELXS97 (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).

(Ia) 5a(RS),6(SR),7(RS),9a(SR),9b(SR)-5-Oxo-1,2,3,5,5a,6,7,9b-octahydro-7,9a-epoxypyrrolo[2,1-a]isoindole-6-carboxylic acid top
Crystal data top
C12H13NO4Dx = 1.415 Mg m−3
Mr = 235.23Melting point = 413–414 K
Monoclinic, P21/cSynchrotron radiation, λ = 0.96990 Å
a = 11.045 (2) ÅCell parameters from 600 reflections
b = 9.2023 (18) Åθ = 4.5–38.0°
c = 11.062 (2) ŵ = 0.23 mm−1
β = 100.91 (3)°T = 100 K
V = 1104.1 (4) Å3Prism, colourless
Z = 40.20 × 0.15 × 0.15 mm
F(000) = 496
Data collection top
MAR CCD
diffractometer		1864 reflections with I > 2σ(I)
φ scanRint = 0.085
Absorption correction: multi-scan
(SCALA; Evans, 2006)		θmax = 38.5°, θmin = 4.5°
Tmin = 0.950, Tmax = 0.960h = −13→14
12183 measured reflectionsk = −11→10
2329 independent reflectionsl = −13→13
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.072H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.189 w = 1/[σ2(Fo2) + (0.08P)2 + 1.P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
2329 reflectionsΔρmax = 0.43 e Å−3
158 parametersΔρmin = −0.43 e Å−3
0 restraintsExtinction correction: SHELXL-2014/7 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: difference Fourier mapExtinction coefficient: 0.104 (9)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.8345 (2)0.9330 (3)0.5467 (2)0.0330 (6)
H1A0.88880.89290.49330.040*
H1B0.88590.97800.62020.040*
C20.7415 (2)1.0430 (3)0.4762 (2)0.0349 (6)
H2A0.77991.10020.41770.042*
H2B0.71231.11060.53410.042*
C30.6333 (2)0.9507 (3)0.4064 (2)0.0312 (6)
H3A0.55310.99890.40590.037*
H3B0.64260.93200.32050.037*
N40.64418 (17)0.8166 (2)0.47832 (17)0.0272 (5)
C50.60154 (19)0.6839 (2)0.4418 (2)0.0253 (5)
O50.52224 (14)0.65677 (18)0.34888 (14)0.0280 (5)
C5A0.66529 (19)0.5736 (2)0.53586 (19)0.0236 (5)
H5A0.61660.55530.60190.028*
C60.7153 (2)0.4306 (2)0.4908 (2)0.0254 (5)
H60.70070.35000.54700.030*
C70.8561 (2)0.4655 (3)0.5143 (2)0.0296 (6)
H70.90500.40680.46450.035*
C80.9021 (2)0.4591 (3)0.6528 (2)0.0330 (6)
H80.95040.38470.69800.040*
C90.8604 (2)0.5799 (3)0.6976 (2)0.0302 (6)
H90.87370.61030.78120.036*
C9A0.7874 (2)0.6583 (2)0.5868 (2)0.0251 (5)
C9B0.7500 (2)0.8164 (3)0.5827 (2)0.0291 (6)
H9B0.72240.84420.66060.035*
O100.85603 (14)0.62038 (18)0.49215 (14)0.0276 (4)
C110.6649 (2)0.3852 (2)0.3585 (2)0.0251 (5)
O110.71540 (16)0.4123 (2)0.27256 (16)0.0374 (5)
O120.56401 (14)0.30469 (18)0.35042 (15)0.0265 (4)
H120.539 (3)0.275 (3)0.272 (3)0.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0350 (13)0.0293 (13)0.0289 (12)−0.0063 (9)−0.0086 (10)−0.0015 (9)
C20.0433 (15)0.0252 (13)0.0318 (14)−0.0031 (10)−0.0039 (11)0.0009 (9)
C30.0333 (13)0.0261 (13)0.0304 (13)0.0025 (9)−0.0033 (10)0.0043 (9)
N40.0257 (10)0.0236 (11)0.0278 (10)0.0004 (7)−0.0064 (8)0.0017 (7)
C50.0192 (10)0.0290 (12)0.0246 (11)−0.0003 (8)−0.0036 (8)0.0016 (8)
O50.0233 (8)0.0293 (9)0.0259 (9)−0.0010 (6)−0.0098 (6)0.0025 (6)
C5A0.0190 (10)0.0270 (12)0.0214 (11)−0.0001 (8)−0.0052 (8)0.0018 (8)
C60.0229 (11)0.0254 (12)0.0235 (11)−0.0011 (8)−0.0066 (8)0.0011 (8)
C70.0215 (11)0.0309 (13)0.0314 (13)0.0017 (9)−0.0075 (9)−0.0039 (9)
C80.0252 (11)0.0324 (13)0.0334 (14)0.0030 (9)−0.0148 (9)0.0008 (9)
C90.0268 (12)0.0341 (14)0.0237 (12)−0.0021 (9)−0.0102 (9)0.0011 (9)
C9A0.0231 (11)0.0260 (12)0.0226 (11)−0.0001 (8)−0.0045 (8)−0.0008 (8)
C9B0.0269 (12)0.0323 (14)0.0236 (11)0.0001 (9)−0.0066 (9)−0.0003 (9)
O100.0222 (8)0.0303 (9)0.0276 (9)−0.0023 (6)−0.0023 (6)−0.0015 (7)
C110.0221 (11)0.0246 (12)0.0254 (12)0.0003 (8)−0.0036 (8)0.0000 (8)
O110.0352 (10)0.0471 (12)0.0276 (10)−0.0085 (8)0.0004 (7)−0.0016 (7)
O120.0205 (8)0.0301 (9)0.0251 (9)−0.0027 (6)−0.0053 (6)−0.0030 (6)
Geometric parameters (Å, º) top
C1—C9B1.524 (4)C6—C111.522 (3)
C1—C21.544 (3)C6—C71.561 (3)
C1—H1A0.9900C6—H61.0000
C1—H1B0.9900C7—O101.446 (3)
C2—C31.548 (3)C7—C81.522 (3)
C2—H2A0.9900C7—H71.0000
C2—H2B0.9900C8—C91.334 (4)
C3—N41.461 (3)C8—H80.9500
C3—H3A0.9900C9—C9A1.516 (3)
C3—H3B0.9900C9—H90.9500
N4—C51.343 (3)C9A—O101.447 (3)
N4—C9B1.480 (3)C9A—C9B1.511 (3)
C5—O51.243 (3)C9B—H9B1.0000
C5—C5A1.527 (3)C11—O111.216 (3)
C5A—C61.546 (3)C11—O121.327 (3)
C5A—C9A1.568 (3)O12—H120.90 (3)
C5A—H5A1.0000
C9B—C1—C2102.2 (2)C11—C6—H6108.8
C9B—C1—H1A111.3C5A—C6—H6108.8
C2—C1—H1A111.3C7—C6—H6108.8
C9B—C1—H1B111.3O10—C7—C8101.44 (18)
C2—C1—H1B111.3O10—C7—C6101.91 (17)
H1A—C1—H1B109.2C8—C7—C6107.0 (2)
C1—C2—C3105.63 (19)O10—C7—H7115.0
C1—C2—H2A110.6C8—C7—H7115.0
C3—C2—H2A110.6C6—C7—H7115.0
C1—C2—H2B110.6C9—C8—C7105.6 (2)
C3—C2—H2B110.6C9—C8—H8127.2
H2A—C2—H2B108.7C7—C8—H8127.2
N4—C3—C2102.45 (18)C8—C9—C9A105.3 (2)
N4—C3—H3A111.3C8—C9—H9127.3
C2—C3—H3A111.3C9A—C9—H9127.3
N4—C3—H3B111.3O10—C9A—C9B112.83 (19)
C2—C3—H3B111.3O10—C9A—C9101.49 (18)
H3A—C3—H3B109.2C9B—C9A—C9125.67 (19)
C5—N4—C3128.07 (19)O10—C9A—C5A98.78 (16)
C5—N4—C9B114.43 (18)C9B—C9A—C5A104.85 (17)
C3—N4—C9B113.42 (18)C9—C9A—C5A110.12 (18)
O5—C5—N4125.7 (2)N4—C9B—C9A101.29 (17)
O5—C5—C5A126.3 (2)N4—C9B—C1103.16 (18)
N4—C5—C5A108.04 (17)C9A—C9B—C1120.6 (2)
C5—C5A—C6119.56 (18)N4—C9B—H9B110.3
C5—C5A—C9A99.73 (17)C9A—C9B—H9B110.3
C6—C5A—C9A101.74 (17)C1—C9B—H9B110.3
C5—C5A—H5A111.5C7—O10—C9A95.65 (17)
C6—C5A—H5A111.5O11—C11—O12124.4 (2)
C9A—C5A—H5A111.5O11—C11—C6123.9 (2)
C11—C6—C5A117.10 (17)O12—C11—C6111.56 (19)
C11—C6—C7112.8 (2)C11—O12—H12109.4 (19)
C5A—C6—C7100.16 (17)
C9B—C1—C2—C3−35.5 (3)C6—C5A—C9A—O1040.32 (19)
C1—C2—C3—N423.1 (3)C5—C5A—C9A—C9B33.7 (2)
C2—C3—N4—C5−157.3 (2)C6—C5A—C9A—C9B156.88 (18)
C2—C3—N4—C9B−1.6 (3)C5—C5A—C9A—C9171.42 (19)
C3—N4—C5—O5−16.7 (4)C6—C5A—C9A—C9−65.4 (2)
C9B—N4—C5—O5−172.2 (2)C5—N4—C9B—C9A13.2 (3)
C3—N4—C5—C5A164.6 (2)C3—N4—C9B—C9A−146.0 (2)
C9B—N4—C5—C5A9.0 (3)C5—N4—C9B—C1138.6 (2)
O5—C5—C5A—C645.6 (3)C3—N4—C9B—C1−20.6 (3)
N4—C5—C5A—C6−135.7 (2)O10—C9A—C9B—N477.5 (2)
O5—C5—C5A—C9A155.1 (2)C9—C9A—C9B—N4−157.9 (2)
N4—C5—C5A—C9A−26.1 (2)C5A—C9A—C9B—N4−29.0 (2)
C5—C5A—C6—C11−18.4 (3)O10—C9A—C9B—C1−35.3 (3)
C9A—C5A—C6—C11−126.8 (2)C9—C9A—C9B—C189.3 (3)
C5—C5A—C6—C7103.9 (2)C5A—C9A—C9B—C1−141.8 (2)
C9A—C5A—C6—C7−4.5 (2)C2—C1—C9B—N433.3 (2)
C11—C6—C7—O1092.5 (2)C2—C1—C9B—C9A145.2 (2)
C5A—C6—C7—O10−32.8 (2)C8—C7—O10—C9A−50.66 (19)
C11—C6—C7—C8−161.48 (19)C6—C7—O10—C9A59.66 (18)
C5A—C6—C7—C873.2 (2)C9B—C9A—O10—C7−171.63 (16)
O10—C7—C8—C932.0 (3)C9—C9A—O10—C751.38 (18)
C6—C7—C8—C9−74.4 (2)C5A—C9A—O10—C7−61.36 (16)
C7—C8—C9—C9A0.9 (3)C5A—C6—C11—O1195.3 (3)
C8—C9—C9A—O10−33.6 (2)C7—C6—C11—O11−20.2 (3)
C8—C9—C9A—C9B−162.9 (2)C5A—C6—C11—O12−88.8 (2)
C8—C9—C9A—C5A70.3 (3)C7—C6—C11—O12155.70 (19)
C5—C5A—C9A—O10−82.84 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O5i0.90 (3)1.75 (3)2.613 (2)157 (3)
C5A—H5A···O12ii1.002.513.234 (3)129
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+1, −y+1, −z+1.
(IIa) 5a(RS),6(RS),7(RS),9a(SR),9b(SR)-5-Oxo-1,2,3,5,5a,6,7,9b-octahydro-7,9a-epoxypyrrolo[2,1-a]isoindole-6-carboxylic acid top
Crystal data top
C12H13NO4F(000) = 248
Mr = 235.23Dx = 1.426 Mg m−3
Triclinic, P1Melting point = 414–416 K
a = 8.4700 (17) ÅSynchrotron radiation, λ = 0.96990 Å
b = 8.5100 (17) ÅCell parameters from 500 reflections
c = 8.5900 (17) Åθ = 3.6–36.0°
α = 94.04 (3)°µ = 0.23 mm−1
β = 111.12 (3)°T = 100 K
γ = 105.17 (3)°Prism, colourless
V = 548.0 (2) Å30.15 × 0.10 × 0.10 mm
Z = 2
Data collection top
MAR CCD
diffractometer		1402 reflections with I > 2σ(I)
φ scanRint = 0.061
Absorption correction: multi-scan
(SCALA; Evans, 2006)		θmax = 38.1°, θmin = 3.4°
Tmin = 0.960, Tmax = 0.969h = −10→10
7090 measured reflectionsk = −10→10
2104 independent reflectionsl = −10→10
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.099H-atom parameters constrained
wR(F2) = 0.240 w = 1/[σ2(Fo2) + (0.06P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.93(Δ/σ)max < 0.001
2104 reflectionsΔρmax = 0.45 e Å−3
155 parametersΔρmin = −0.36 e Å−3
0 restraintsExtinction correction: SHELXL-2014/7 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: difference Fourier mapExtinction coefficient: 0.138 (11)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.1779 (3)0.0068 (2)0.2264 (2)0.0322 (5)
H1A0.0733−0.03310.11710.039*
H1B0.2531−0.06680.23740.039*
C20.1215 (3)0.0169 (2)0.3765 (2)0.0324 (5)
H2A0.0900−0.09320.40810.039*
H2B0.01810.05920.34860.039*
C30.2874 (2)0.1392 (2)0.5222 (2)0.0288 (5)
H3A0.25290.20890.59340.035*
H3B0.36280.07970.59490.035*
N40.37879 (19)0.23864 (17)0.42848 (16)0.0261 (4)
C50.5531 (2)0.3199 (2)0.4832 (2)0.0250 (4)
O50.65982 (17)0.35299 (15)0.63512 (13)0.0299 (3)
C5A0.5950 (2)0.3619 (2)0.3297 (2)0.0233 (4)
H5A0.59490.47690.31270.028*
C60.7574 (2)0.32415 (19)0.3142 (2)0.0245 (4)
H60.81500.27540.41400.029*
C70.6593 (3)0.1818 (2)0.1503 (2)0.0276 (5)
H70.73380.11380.13330.033*
C80.5722 (2)0.2548 (2)−0.0027 (2)0.0264 (5)
H80.61080.2775−0.09210.032*
C90.4292 (3)0.2805 (2)0.0152 (2)0.0284 (5)
H90.34310.3223−0.05980.034*
C9A0.4358 (2)0.2276 (2)0.1826 (2)0.0256 (5)
C9B0.2840 (2)0.1875 (2)0.24142 (19)0.0267 (5)
H9B0.20220.25410.19500.032*
O100.51146 (16)0.09341 (13)0.18544 (14)0.0258 (3)
C110.8967 (2)0.4657 (2)0.2990 (2)0.0259 (5)
O110.88416 (17)0.60281 (15)0.27854 (15)0.0338 (4)
O121.04071 (16)0.42233 (14)0.31124 (15)0.0312 (4)
H121.13550.50930.31630.047*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0352 (10)0.0244 (9)0.0294 (8)−0.0016 (8)0.0132 (7)−0.0032 (7)
C20.0364 (10)0.0254 (9)0.0311 (8)−0.0003 (8)0.0158 (7)0.0030 (7)
C30.0365 (9)0.0234 (9)0.0290 (8)0.0035 (8)0.0201 (6)0.0019 (7)
N40.0308 (8)0.0214 (7)0.0246 (6)0.0012 (6)0.0152 (5)−0.0014 (5)
C50.0316 (9)0.0159 (7)0.0263 (8)0.0045 (7)0.0131 (6)−0.0028 (6)
O50.0364 (7)0.0281 (6)0.0205 (5)0.0017 (5)0.0130 (4)−0.0033 (5)
C5A0.0284 (9)0.0177 (8)0.0227 (7)0.0022 (7)0.0131 (6)−0.0005 (6)
C60.0355 (9)0.0164 (8)0.0232 (7)0.0043 (7)0.0165 (6)0.0005 (6)
C70.0335 (9)0.0192 (8)0.0277 (8)−0.0004 (7)0.0169 (6)−0.0048 (6)
C80.0373 (10)0.0199 (8)0.0209 (7)0.0025 (7)0.0158 (6)−0.0026 (6)
C90.0368 (10)0.0211 (8)0.0229 (8)0.0029 (8)0.0118 (7)−0.0001 (6)
C9A0.0344 (9)0.0168 (8)0.0239 (7)0.0043 (7)0.0128 (6)0.0000 (6)
C9B0.0327 (9)0.0214 (8)0.0240 (8)0.0032 (7)0.0134 (6)−0.0021 (6)
O100.0337 (6)0.0164 (5)0.0277 (5)0.0033 (5)0.0165 (4)−0.0009 (4)
C110.0316 (9)0.0227 (9)0.0204 (7)0.0024 (7)0.0126 (6)−0.0045 (6)
O110.0375 (7)0.0228 (6)0.0390 (6)0.0042 (6)0.0170 (5)0.0031 (5)
O120.0309 (7)0.0232 (6)0.0403 (6)0.0040 (5)0.0189 (5)0.0015 (5)
Geometric parameters (Å, º) top
C1—C21.532 (3)C6—C111.500 (3)
C1—C9B1.534 (3)C6—C71.590 (2)
C1—H1A0.9900C6—H61.0000
C1—H1B0.9900C7—O101.427 (2)
C2—C31.552 (2)C7—C81.521 (3)
C2—H2A0.9900C7—H71.0000
C2—H2B0.9900C8—C91.344 (3)
C3—N41.472 (2)C8—H80.9500
C3—H3A0.9900C9—C9A1.522 (2)
C3—H3B0.9900C9—H90.9500
N4—C51.341 (2)C9A—O101.446 (2)
N4—C9B1.485 (2)C9A—C9B1.513 (3)
C5—O51.250 (2)C9B—H9B1.0000
C5—C5A1.526 (3)C11—O111.218 (2)
C5A—C61.540 (3)C11—O121.336 (2)
C5A—C9A1.576 (2)O12—H120.9239
C5A—H5A1.0000
C2—C1—C9B102.15 (14)C11—C6—H6108.7
C2—C1—H1A111.3C5A—C6—H6108.7
C9B—C1—H1A111.3C7—C6—H6108.7
C2—C1—H1B111.3O10—C7—C8102.71 (15)
C9B—C1—H1B111.3O10—C7—C699.48 (13)
H1A—C1—H1B109.2C8—C7—C6109.15 (14)
C1—C2—C3104.39 (16)O10—C7—H7114.6
C1—C2—H2A110.9C8—C7—H7114.6
C3—C2—H2A110.9C6—C7—H7114.6
C1—C2—H2B110.9C9—C8—C7105.52 (17)
C3—C2—H2B110.9C9—C8—H8127.2
H2A—C2—H2B108.9C7—C8—H8127.2
N4—C3—C2102.16 (13)C8—C9—C9A104.59 (17)
N4—C3—H3A111.3C8—C9—H9127.7
C2—C3—H3A111.3C9A—C9—H9127.7
N4—C3—H3B111.3O10—C9A—C9B111.77 (14)
C2—C3—H3B111.3O10—C9A—C9102.12 (14)
H3A—C3—H3B109.2C9B—C9A—C9126.44 (16)
C5—N4—C3127.10 (15)O10—C9A—C5A100.18 (14)
C5—N4—C9B115.10 (15)C9B—C9A—C5A105.83 (13)
C3—N4—C9B113.07 (13)C9—C9A—C5A107.50 (14)
O5—C5—N4124.50 (18)N4—C9B—C9A102.11 (13)
O5—C5—C5A127.21 (17)N4—C9B—C1101.06 (14)
N4—C5—C5A108.28 (14)C9A—C9B—C1120.38 (16)
C5—C5A—C6117.75 (15)N4—C9B—H9B110.7
C5—C5A—C9A101.00 (14)C9A—C9B—H9B110.7
C6—C5A—C9A101.86 (13)C1—C9B—H9B110.7
C5—C5A—H5A111.7C7—O10—C9A96.02 (13)
C6—C5A—H5A111.7O11—C11—O12123.30 (17)
C9A—C5A—H5A111.7O11—C11—C6125.93 (18)
C11—C6—C5A117.00 (15)O12—C11—C6110.77 (15)
C11—C6—C7113.55 (15)C11—O12—H12113.8
C5A—C6—C799.72 (13)
C9B—C1—C2—C3−40.2 (2)C6—C5A—C9A—O1032.99 (16)
C1—C2—C3—N424.99 (19)C5—C5A—C9A—C9B27.56 (18)
C2—C3—N4—C5−154.32 (18)C6—C5A—C9A—C9B149.26 (14)
C2—C3—N4—C9B−0.1 (2)C5—C5A—C9A—C9165.01 (15)
C3—N4—C5—O5−16.0 (3)C6—C5A—C9A—C9−73.29 (18)
C9B—N4—C5—O5−169.80 (16)C5—N4—C9B—C9A8.4 (2)
C3—N4—C5—C5A163.66 (15)C3—N4—C9B—C9A−149.09 (15)
C9B—N4—C5—C5A9.9 (2)C5—N4—C9B—C1133.04 (17)
O5—C5—C5A—C647.1 (2)C3—N4—C9B—C1−24.4 (2)
N4—C5—C5A—C6−132.62 (15)O10—C9A—C9B—N485.85 (15)
O5—C5—C5A—C9A156.89 (18)C9—C9A—C9B—N4−148.99 (15)
N4—C5—C5A—C9A−22.81 (19)C5A—C9A—C9B—N4−22.27 (18)
C5—C5A—C6—C11−123.93 (16)O10—C9A—C9B—C1−24.8 (2)
C9A—C5A—C6—C11126.75 (15)C9—C9A—C9B—C1100.3 (2)
C5—C5A—C6—C7113.23 (14)C5A—C9A—C9B—C1−132.96 (15)
C9A—C5A—C6—C73.91 (16)C2—C1—C9B—N438.51 (18)
C11—C6—C7—O10−165.65 (15)C2—C1—C9B—C9A149.76 (16)
C5A—C6—C7—O10−40.40 (16)C8—C7—O10—C9A−49.46 (13)
C11—C6—C7—C8−58.5 (2)C6—C7—O10—C9A62.79 (14)
C5A—C6—C7—C866.71 (18)C9B—C9A—O10—C7−171.68 (12)
O10—C7—C8—C930.75 (16)C9—C9A—O10—C750.59 (14)
C6—C7—C8—C9−74.15 (18)C5A—C9A—O10—C7−59.96 (14)
C7—C8—C9—C9A1.83 (16)C5A—C6—C11—O11−8.9 (2)
C8—C9—C9A—O10−33.38 (16)C7—C6—C11—O11106.5 (2)
C8—C9—C9A—C9B−162.43 (15)C5A—C6—C11—O12171.02 (12)
C8—C9—C9A—C5A71.53 (17)C7—C6—C11—O12−73.58 (19)
C5—C5A—C9A—O10−88.71 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O5i0.921.702.607 (2)165
C9—H9···O11ii0.952.423.362 (3)172
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, −y+1, −z.
 

Acknowledgements

This work was supported by the Ministry of Education and Science of the Russian Federation (Agreement 02.a03.21.0008), and the Russian Foundation for Basic Research (grant No. 15-33-50016).

References

First citationAsher, V., Becu, C., Anteunis, M. J. O. & Callens, R. (1981). Tetrahedron Lett. 22, 141–144.  CrossRef CAS Web of Science Google Scholar
 First citationBattye, T. G. G., Kontogiannis, L., Johnson, O., Powell, H. R. & Leslie, A. G. W. (2011). Acta Cryst. D67, 271–281.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationBlokzijl, W., Blandamer, M. J. & Engberts, J. (1991). J. Am. Chem. Soc. 113, 4241–4246.  CrossRef CAS Web of Science Google Scholar
 First citationEvans, P. (2006). Acta Cryst. D62, 72–82.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationGroenendaal, B., Ruijter, E., de Kanter, F., Lutz, M., Spek, A. L. & Orru, R. V. (2008). Org. Biomol. Chem. 6, 3158–3165.  Web of Science CSD CrossRef PubMed CAS Google Scholar
 First citationLu, Q., Huang, X., Song, G., Sun, C.-M., Jasinski, J. P., Keeley, A. C. & Zhang, W. (2013). ACS Comb. Sci. 15, 350–355.  Web of Science CSD CrossRef CAS PubMed Google Scholar
 First citationMarXperts. (2015). Automar. MarXperts GmbH, D-22844 Norderstedt, Germany.  Google Scholar
 First citationNakamura, M., Takahashi, I., Yamada, S., Dobashi, Y. & Kitagawa, O. (2011). Tetrahedron Lett. 52, 53–55.  Web of Science CrossRef CAS Google Scholar
 First citationNikolic, N. A. & Beak, P. (1997). Org. Synth. 74, 23–32.  CAS Google Scholar
 First citationParker, K. A. & Adamchuk, M. R. (1978). Tetrahedron Lett. 19, 1689–1692.  CrossRef Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSheldrick, G. M. (2015). Acta Cryst. C71, 3–8.  Web of Science CrossRef IUCr Journals Google Scholar
 First citationShono, T., Matsumura, Y., Tsubata, K. O. & Takata, J. (1981). Chem. Lett. 10, 1121–1124.  CrossRef Web of Science Google Scholar
 First citationToze, F. A. A., Poplevin, D. S., Zubkov, F. I., Nikitina, E. V., Porras, C. & Khrustalev, V. N. (2015). Acta Cryst. E71, o729–o730.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationVarlamov, A. V., Boltukhina, E. V., Zubkov, F. I., Nikitina, E. V. & Turchin, K. F. (2006). J. Heterocycl. Chem. 43, 1479–1495.  CSD CrossRef CAS Google Scholar
 First citationZubkov, F. I., Airiyan, I. K., Ershova, J. D., Galeev, T. R., Zaytsev, V. P., Nikitina, E. V. & Varlamov, A. V. (2012). RSC Adv. 2, 4103–4109.  Web of Science CrossRef CAS Google Scholar
 First citationZubkov, F. I., Nikitina, E. V., Galeev, T. R., Zaytsev, V. P., Khrustalev, V. N., Novikov, R. A., Orlova, D. N. & Varlamov, A. V. (2014). Tetrahedron, 70, 1659–1690.  Web of Science CSD CrossRef CAS Google Scholar
 First citationZubkov, F. I., Zaytsev, V. P., Nikitina, E. V., Khrustalev, V. N., Gozun, S. V., Boltukhina, E. V. & Varlamov, A. V. (2011). Tetrahedron, 67, 9148–9163.  Web of Science CSD CrossRef CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 10| October 2016| Pages 1429-1433
https://doi.org/10.1107/S2056989016014420
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS