(3aR,8aS,9S,9aR)-9-Hydroxy­perhydro­furo[3,2-f]indolizin-6-one

Švorc, Ľ.; Vrábel, V.; Žúžiová, J.; Marchalín, Š.; Kožíšek, J.

doi:10.1107/S1600536809024283

organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Pages o1731-o1732

doi:10.1107/S1600536809024283

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(3aR,8aS,9S,9aR)-9-Hydroxyperhydrofuro[3,2-f]indolizin-6-one

Ľubomír Švorc,^a Viktor Vrábel,^a ^* Jozefína Žúžiová,^b Štefan Marchalín ^b and Jozef Kožíšek ^c

^aInstitute of Analytical Chemistry, Faculty of Chemical and Food Technology, Slovak Technical University, Radlinského 9, SK-812 37 Bratislava, Slovak Republic 81237, ^bInstitute of Organic Chemistry, Catalysis and Petrochemistry, Faculty of Chemical and Food Technology, Slovak Technical University, Radlinského 9, SK-812 37 Bratislava, Slovak Republic 81237, and ^cInstitute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak Technical University, Radlinského 9, Bratislava, Slovak Republic 81237
^*Correspondence e-mail: viktor.vrabel@stuba.sk

(Received 27 May 2009; accepted 24 June 2009; online 1 July 2009)

In the title compound, C₁₀H₁₅NO₃, the central six-membered ring of the indolizine system adopts a chair conformation, while the oxopyrrolidine and hydrofuran rings attached to the indolizine ring system have envelope conformations. In the crystal, the molecules form chains parallel to the b axis via intermolecular O—H⋯O hydrogen bonds. The absolute configuration was assigned from the synthesis.

Related literature

For general properties of indolizines see: Gundersen et al. (2007 ); Sundaram et al. (2007 ); Mikael (1999 ); Pyne (2005 ); Karanjule et al. (2006 ); Chaudhari et al. (2006 ); Martin et al. (2005 ). For the synthesis of the title compound see: Šafář et al. (2008 ). For related structures, see: Vrábel et al. (2004 ); Švorc et al. (2009 ). Camus et al. (2003 ) For puckering parameters, see: Cremer & Pople (1975 ).

Experimental

Crystal data

C₁₀H₁₅NO₃
M_r = 197.23
Monoclinic, P 2₁
a = 6.2856 (1) Å
b = 6.4521 (1) Å
c = 11.7698 (2) Å
β = 98.631 (2)°
V = 471.92 (1) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 298 K
0.45 × 0.29 × 0.04 mm

Data collection

Oxford Diffraction Gemini R CCD diffractometer
Absorption correction: analytical (Clark & Reid, 1995 ) T_min = 0.962, T_max = 0.996
12197 measured reflections
1359 independent reflections
1151 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.088
S = 1.09
1359 reflections
131 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.12 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2A⋯O3ⁱ	0.82 (3)	2.15 (3)	2.9233 (19)	157 (2)
Symmetry code: (i) $[-x+2, y-{\script{1\over 2}}, -z+2]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2001 ); software used to prepare material for publication: enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809024283/bg2263sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809024283/bg2263Isup2.hkl

checkCIF report

Comment top

Indolizines are electron-rich heterocycles with very low oxidation potential. Functionalized indolizines are common substructures found in biologically important natural products and synthetic pharmaceuticals. Due to the various biological functions associated with this skeleton, it has been frequently employed as a key scaffold in the drug industry (Gundersen et al., 2007). The indolizine derivatives show antibacterial, antiviral, antiherpes, anticancer, antifungal, antihelmintic and insecticidal activity (Sundaram et al., 2007). Indolizine alkaloids are excellent inhibitors of biologically important pathways. These include the binding and processing of glycoproteins, potent glycosidase inhibitory activities (Pyne, 2005), activity against AIDS virus HIV and some carcinogenic cells (Mikael, 1999). Castanospermine (Karanjule et al., 2006), swainsonine (Martin et al., 2005) and lentiginosine (Chaudhari et al., 2006) have shown respective glycosidase and mannosidase inhibitory activities, respectively. While an impressive number of total syntheses of polyhydroxylated indolizines and their non-natural analogues in chiral or racemic forms have been reported, the monohydroxylated indolizines have attracted far less attention.

Based on these facts and in contitutation of our interest in developing simple and efficient route for the synthesis of novel monohydroxylated indolizine derivatives, we report here the synthesis, molecular and crystal structure of the title compound, (I). The absolute configuration was established by synthesis and is depicted in the scheme and figure. The expected stereochemistry of atoms C5, C6, C7 and C10 was confirmed as S, S, R and R, respectively (Fig. 1). The central six-membered ring is not planar and adopts a chair conformation (Cremer & Pople, 1975). A calculation of least-squares planes shows that this ring is puckered in such a manner that the four atoms C5, C6, C10 and C11 are coplanar to within 0.019 (2) Å, while atoms N1 and C7 are displaced from this plane on opposite sides, with out-of-plane displacements of -0.591 (2) and 0.565 (1) Å, respectively. The oxopyrrolidine and hydrofuran rings are each distorted towards an envelope conformation, with atoms C4 and C10 as the flaps. The displacements of atoms C4 and C10 from the mean planes of the remaining four atoms are 0.316 (2) and 0.642 (2) Å, respectively. The central six-membered N-ring is approximately perpendicular to the hydrofuran ring (dihedral angle between plane defined by atoms C5, C6, C10 and C11 and plane defined by atoms C7, O3, C8 and C9) is 82.2 (1)°. As was mentioned in previous papers (Vrábel et al., 2004; Švorc et al., 2009), the N1—C5 and N1—C11 bonds are approximately equivalent and both are much longer than the N1—C2 bond. Atom N1 is sp²-hybridized, as evidenced by the sum of the valence angles around it (357.3 (2)°). These data are consistent with conjugation of the lone-pair electrons on N1 with the adjacent carbonyl, similar to what is observed for amides. Intermolecular O—H···O hydrogen bonds link the molecules of (I) into extended chains, which run parallel to the b axis (Fig. 2) and help to stabilize the crystal structure of the compound. Atom O2 participates as acceptor and atom O3 as donator in these intermolecular hydrogen bonds. Bond lengths and angles in the indolizine ring system are in good agreement with values from the literature (Camus et al., 2003).

Related literature top

For general properties of indolizines see: Gundersen et al. (2007); Sundaram et al. (2007); Mikael (1999); Pyne (2005); Karanjule et al. (2006); Chaudhari et al. (2006); Martin et al. (2005). For the synthesis of the title compound see: Šafář et al. (2008). For related structures, see: Vrábel et al. (2004); Švorc et al. (2009). Camus et al. (2003) For puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound (3aR,8aS,9S,9aR)-9-hydroxyoctahydrofuro[3,2-f]indolizin- 6(4H)-one was prepared according literature procedures of Šafář et al. (2008).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: enCIFer (Allen et al., 2004).

Figures top

	Fig. 1. Molecular structure of (I) with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level (Brandenburg, 2001).
	Fig. 2. Packing view of (I), projected along a and showing the formation of chains running along b.

(3aR,8aS,9S,9aR)-9- Hydroxyperhydrofuro[3,2-f]indolizin-6-one top

Crystal data top

C₁₀H₁₅NO₃	F(000) = 212
M_r = 197.23	D_x = 1.388 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 7268 reflections
a = 6.2856 (1) Å	θ = 3.2–29.4°
b = 6.4521 (1) Å	µ = 0.10 mm⁻¹
c = 11.7698 (2) Å	T = 298 K
β = 98.631 (2)°	Block, white
V = 471.92 (1) Å³	0.45 × 0.29 × 0.04 mm
Z = 2

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	1359 independent reflections
Radiation source: fine-focus sealed tube	1151 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
Detector resolution: 10.4340 pixels mm^-1	θ_max = 29.5°, θ_min = 3.5°
Rotation method data acquisition using ω and ϕ scans	h = −8→8
Absorption correction: analytical (Clark & Reid, 1995)	k = −8→8
T_min = 0.962, T_max = 0.996	l = −16→16
12197 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.088	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ²(F_o²) + (0.0589P)² + 0.002P] where P = (F_o² + 2F_c²)/3
1359 reflections	(Δ/σ)_max < 0.001
131 parameters	Δρ_max = 0.18 e Å⁻³
1 restraint	Δρ_min = −0.12 e Å⁻³

Crystal data top

C₁₀H₁₅NO₃	V = 471.92 (1) Å³
M_r = 197.23	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 6.2856 (1) Å	µ = 0.10 mm⁻¹
b = 6.4521 (1) Å	T = 298 K
c = 11.7698 (2) Å	0.45 × 0.29 × 0.04 mm
β = 98.631 (2)°

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	1359 independent reflections
Absorption correction: analytical (Clark & Reid, 1995)	1151 reflections with I > 2σ(I)
T_min = 0.962, T_max = 0.996	R_int = 0.024
12197 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	1 restraint
wR(F²) = 0.088	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	Δρ_max = 0.18 e Å⁻³
1359 reflections	Δρ_min = −0.12 e Å⁻³
131 parameters

Special details top

Experimental. (face-indexed; Oxford Diffraction, 2006)

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C2	0.4873 (3)	0.2817 (3)	0.72325 (14)	0.0411 (4)
C3	0.4877 (3)	0.1873 (3)	0.84157 (15)	0.0459 (4)
H3B	0.3467	0.1332	0.8494	0.055*
H3A	0.5921	0.0759	0.8550	0.055*
C4	0.5484 (3)	0.3645 (3)	0.92481 (13)	0.0387 (4)
H4B	0.6470	0.3177	0.9912	0.046*
H4A	0.4216	0.4225	0.9506	0.046*
C5	0.6564 (2)	0.5248 (3)	0.85636 (11)	0.0332 (3)
H5A	0.6105	0.6647	0.8742	0.040*
C6	0.9007 (2)	0.5135 (3)	0.87248 (12)	0.0344 (3)
H6A	0.9426	0.3684	0.8650	0.041*
C7	0.9925 (2)	0.6393 (3)	0.78316 (14)	0.0380 (4)
H7A	1.1473	0.6117	0.7900	0.046*
C8	0.9599 (3)	0.9602 (3)	0.69052 (17)	0.0550 (5)
H8B	1.0849	1.0494	0.6934	0.066*
H8A	0.8315	1.0444	0.6723	0.066*
C9	0.9646 (3)	0.7923 (4)	0.60051 (16)	0.0532 (5)
H9B	1.1088	0.7732	0.5823	0.064*
H9A	0.8680	0.8251	0.5306	0.064*
C10	0.8887 (3)	0.5997 (3)	0.65890 (13)	0.0431 (4)
H10A	0.9444	0.4726	0.6286	0.052*
C11	0.6434 (3)	0.5962 (3)	0.64646 (13)	0.0468 (4)
H11B	0.5898	0.7367	0.6500	0.056*
H11A	0.5847	0.5383	0.5723	0.056*
N1	0.5732 (2)	0.4730 (2)	0.73730 (11)	0.0396 (3)
O1	0.4241 (2)	0.1993 (3)	0.63124 (11)	0.0624 (4)
O2	0.9924 (2)	0.5850 (2)	0.98351 (11)	0.0487 (3)
H2A	0.993 (4)	0.493 (5)	1.031 (2)	0.060 (7)*
O3	0.9608 (2)	0.85665 (19)	0.79966 (10)	0.0471 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C2	0.0366 (7)	0.0539 (10)	0.0319 (7)	−0.0097 (7)	0.0025 (6)	0.0024 (7)
C3	0.0520 (9)	0.0514 (10)	0.0339 (8)	−0.0129 (8)	0.0044 (7)	0.0047 (7)
C4	0.0391 (7)	0.0485 (10)	0.0291 (7)	−0.0010 (7)	0.0071 (6)	0.0031 (7)
C5	0.0373 (7)	0.0380 (8)	0.0242 (6)	0.0012 (6)	0.0045 (5)	−0.0003 (6)
C6	0.0375 (7)	0.0378 (8)	0.0263 (7)	0.0009 (6)	−0.0004 (5)	−0.0011 (7)
C7	0.0325 (7)	0.0471 (10)	0.0345 (8)	0.0000 (7)	0.0057 (6)	0.0001 (7)
C8	0.0631 (11)	0.0518 (11)	0.0482 (10)	−0.0164 (9)	0.0025 (8)	0.0130 (9)
C9	0.0532 (9)	0.0700 (13)	0.0378 (9)	−0.0141 (10)	0.0116 (7)	0.0122 (9)
C10	0.0545 (9)	0.0477 (10)	0.0290 (7)	−0.0050 (8)	0.0129 (6)	−0.0009 (7)
C11	0.0544 (9)	0.0563 (10)	0.0271 (7)	−0.0143 (9)	−0.0026 (6)	0.0087 (8)
N1	0.0407 (7)	0.0506 (8)	0.0255 (6)	−0.0095 (6)	−0.0019 (5)	0.0053 (6)
O1	0.0721 (8)	0.0765 (10)	0.0357 (6)	−0.0308 (8)	−0.0011 (6)	−0.0067 (7)
O2	0.0583 (7)	0.0559 (8)	0.0275 (6)	−0.0166 (6)	−0.0082 (5)	0.0040 (6)
O3	0.0619 (7)	0.0427 (7)	0.0362 (6)	−0.0111 (6)	0.0053 (5)	0.0005 (6)

Geometric parameters (Å, º) top

C2—O1	1.218 (2)	C7—C10	1.531 (2)
C2—N1	1.347 (2)	C7—H7A	0.9800
C2—C3	1.520 (2)	C8—O3	1.447 (2)
C3—C4	1.517 (3)	C8—C9	1.519 (3)
C3—H3B	0.9700	C8—H8B	0.9700
C3—H3A	0.9700	C8—H8A	0.9700
C4—C5	1.530 (2)	C9—C10	1.531 (3)
C4—H4B	0.9700	C9—H9B	0.9700
C4—H4A	0.9700	C9—H9A	0.9700
C5—N1	1.4591 (18)	C10—C11	1.527 (2)
C5—C6	1.5204 (19)	C10—H10A	0.9800
C5—H5A	0.9800	C11—N1	1.453 (2)
C6—O2	1.4238 (17)	C11—H11B	0.9700
C6—C7	1.510 (2)	C11—H11A	0.9700
C6—H6A	0.9800	O2—H2A	0.82 (3)
C7—O3	1.433 (2)

O1—C2—N1	125.45 (17)	C6—C7—H7A	108.9
O1—C2—C3	126.54 (18)	C10—C7—H7A	108.9
N1—C2—C3	108.00 (15)	O3—C8—C9	106.96 (17)
C4—C3—C2	104.81 (15)	O3—C8—H8B	110.3
C4—C3—H3B	110.8	C9—C8—H8B	110.3
C2—C3—H3B	110.8	O3—C8—H8A	110.3
C4—C3—H3A	110.8	C9—C8—H8A	110.3
C2—C3—H3A	110.8	H8B—C8—H8A	108.6
H3B—C3—H3A	108.9	C8—C9—C10	103.06 (14)
C3—C4—C5	104.93 (12)	C8—C9—H9B	111.2
C3—C4—H4B	110.8	C10—C9—H9B	111.2
C5—C4—H4B	110.8	C8—C9—H9A	111.2
C3—C4—H4A	110.8	C10—C9—H9A	111.2
C5—C4—H4A	110.8	H9B—C9—H9A	109.1
H4B—C4—H4A	108.8	C11—C10—C9	110.32 (16)
N1—C5—C6	108.57 (12)	C11—C10—C7	111.95 (13)
N1—C5—C4	103.15 (13)	C9—C10—C7	100.16 (14)
C6—C5—C4	114.91 (13)	C11—C10—H10A	111.3
N1—C5—H5A	110.0	C9—C10—H10A	111.3
C6—C5—H5A	110.0	C7—C10—H10A	111.3
C4—C5—H5A	110.0	N1—C11—C10	110.56 (13)
O2—C6—C7	108.67 (13)	N1—C11—H11B	109.5
O2—C6—C5	111.18 (13)	C10—C11—H11B	109.5
C7—C6—C5	111.84 (12)	N1—C11—H11A	109.5
O2—C6—H6A	108.4	C10—C11—H11A	109.5
C7—C6—H6A	108.4	H11B—C11—H11A	108.1
C5—C6—H6A	108.4	C2—N1—C11	124.84 (15)
O3—C7—C6	110.87 (13)	C2—N1—C5	114.01 (14)
O3—C7—C10	104.17 (14)	C11—N1—C5	118.47 (13)
C6—C7—C10	114.99 (13)	C6—O2—H2A	110.8 (18)
O3—C7—H7A	108.9	C7—O3—C8	108.27 (13)

O1—C2—C3—C4	−171.33 (18)	O3—C7—C10—C9	41.27 (16)
N1—C2—C3—C4	9.79 (19)	C6—C7—C10—C9	162.80 (14)
C2—C3—C4—C5	−19.80 (18)	C9—C10—C11—N1	−156.02 (15)
C3—C4—C5—N1	22.25 (17)	C7—C10—C11—N1	−45.4 (2)
C3—C4—C5—C6	−95.73 (16)	O1—C2—N1—C11	−12.7 (3)
N1—C5—C6—O2	173.44 (14)	C3—C2—N1—C11	166.20 (16)
C4—C5—C6—O2	−71.68 (18)	O1—C2—N1—C5	−173.78 (17)
N1—C5—C6—C7	51.76 (17)	C3—C2—N1—C5	5.11 (19)
C4—C5—C6—C7	166.64 (13)	C10—C11—N1—C2	−105.48 (18)
O2—C6—C7—O3	−54.82 (17)	C10—C11—N1—C5	54.8 (2)
C5—C6—C7—O3	68.30 (16)	C6—C5—N1—C2	104.77 (16)
O2—C6—C7—C10	−172.63 (14)	C4—C5—N1—C2	−17.57 (17)
C5—C6—C7—C10	−49.52 (19)	C6—C5—N1—C11	−57.6 (2)
O3—C8—C9—C10	19.3 (2)	C4—C5—N1—C11	−179.96 (15)
C8—C9—C10—C11	82.07 (18)	C6—C7—O3—C8	−154.92 (13)
C8—C9—C10—C7	−36.05 (18)	C10—C7—O3—C8	−30.69 (17)
O3—C7—C10—C11	−75.64 (18)	C9—C8—O3—C7	7.04 (19)
C6—C7—C10—C11	45.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3ⁱ	0.82 (3)	2.15 (3)	2.9233 (19)	157 (2)

Symmetry code: (i) −x+2, y−1/2, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₀H₁₅NO₃
M_r	197.23
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	298
a, b, c (Å)	6.2856 (1), 6.4521 (1), 11.7698 (2)
β (°)	98.631 (2)
V (Å³)	471.92 (1)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.45 × 0.29 × 0.04

Data collection
Diffractometer	Oxford Diffraction Gemini R CCD diffractometer
Absorption correction	Analytical (Clark & Reid, 1995)
T_min, T_max	0.962, 0.996
No. of measured, independent and observed [I > 2σ(I)] reflections	12197, 1359, 1151
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.692

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.088, 1.09
No. of reflections	1359
No. of parameters	131
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.12

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2001), enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3ⁱ	0.82 (3)	2.15 (3)	2.9233 (19)	157 (2)

Symmetry code: (i) −x+2, y−1/2, −z+2.

Acknowledgements

The authors thank the Grant Agency of the Slovak Republic (grant Nos. 1/0161/08 and 1/0817/08) and the Structural Funds, Interreg IIIA for financial support in purchasing the diffractometer and the Development Agency under contract No. APVV-0210–07.

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