(Z)-1,2:5,6-Di-O-isopropyl­idene-α-d-ribo-hexofuranos-3-ulose O-benzyl­oxime

Burkhardt, A.; Eriksson, L.; Widmalm, G.; Cumpstey, I.

doi:10.1107/S1600536809006333

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page o633

doi:10.1107/S1600536809006333

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(Z)-1,2:5,6-Di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose O-benzyloxime

Anja Burkhardt,^a Lars Eriksson,^b ^* Göran Widmalm ^a and Ian Cumpstey ^a

^aDepartment of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden, and ^bDivision of Structural Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
^*Correspondence e-mail: lerik@struc.su.se

(Received 13 February 2009; accepted 20 February 2009; online 28 February 2009)

The title compound, C₁₉H₂₅NO₆, is a Z diastereomer in which the phenyl ring of the 3-benzyloxime substituent and the 5,6-O-isopropylidene acetal are both located on the Si-face of the C=N double bond. Intermolecular C—H⋯O interactions result in helical chains along the b axis of the monoclinic unit cell.

Related literature

For background to sugar-based oxime derivatives, see: Tronchet et al. (1979 , 1981 , 1989 ); Peri et al. (2004 ). For the synthesis, see: Plenkiewicz et al. (1974 ); Fernández-González & Alonso (2006 ). For ring puckering analysis, see: Cremer & Pople (1975 ). For C–H⋯O interactions, see: Gatti et al. (2002 ). For the synthesis of a reactant, see: Shing et al. (1996 ).

Experimental

Crystal data

C₁₉H₂₅NO₆
M_r = 363.40
Monoclinic, P 2₁
a = 11.8012 (12) Å
b = 6.0019 (5) Å
c = 13.7021 (11) Å
β = 95.122 (11)°
V = 966.64 (15) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.30 × 0.05 × 0.04 mm

Data collection

Stoe IPDS diffractometer
Absorption correction: none
9449 measured reflections
2558 independent reflections
2023 reflections with I > 2σ(I)
R_int = 0.104

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.131
S = 0.99
2558 reflections
235 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.31 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O2ⁱ	0.98	2.43	3.386 (3)	164
C10—H10A⋯O3ⁱⁱ	0.97	2.46	3.387 (3)	160
Symmetry codes: (i) $[-x, y-{\script{1\over 2}}, -z]$ ; (ii) $[-x, y-{\script{1\over 2}}, -z+1]$ .

Data collection: EXPOSE in IPDS Software (Stoe & Cie, 1997 ); cell refinement: CELL in IPDS Software; data reduction: INTEGRATE in IPDS Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1990 ); software used to prepare material for publication: PLATON (Spek, 2009 ), XP and SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809006333/ng2545sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809006333/ng2545Isup2.hkl

checkCIF report

Comment top

Oxime derivatives of carbohydrates are important precursors for preparation of monosaccharide building blocks in disaccharide mimic synthesis. (Tronchet et al., 1979, 1981,1989; Peri et al., 2004)

The title compound (I) can be easily synthesized by condensation of the corresponding keto sugar with O-benzylhydroxylamine hydrochloride in pyridine in good yield. (Plenkiewicz et al., 1974; Fernández-González & Alonso, 2006) Crystallization from pentane/ethyl acetate gave exclusively the Z diastereomer of I. The crystal structure of I is depicted in Fig. 1 and reveals a twist form for the sugar furanose ring (O1, C1, C2, C3, C4) according to the puckering parameters q₂ = 0.257 (2) Å and Φ₂ = 164.8 (5)°. (Cremer & Pople, 1975) This conformation is also observed for the 1,2-O-isopropylidene (O2, C1, C2, O3, C7; q₂ = 0.237 (2) Å, Φ₂ = 162.1 (6)°) and the 5,6-O-isopropylidene acetal (O5, C5, C6, O6, C17; q₂ = 0.310 (3) Å, Φ₂ = 15.4 (6)°). The phenyl ring of the 3-benzyloxime substituent at C3 and the furanose mean plane (O1, C1 to C4) are twisted to each other by 87.2 (2)° indicated by an N1—O4—C10—C11 torsion angle of -74.9 (3)°. The Re-face of the C=N double bond is shielded by a methyl group of the 1,2-O-isopropylidene entity, while the Si-face is shielded by the benzyl group of the 3-benzyloxime substituent and the 5,6-O-isopropylidene protecting group. Assuming that the latter two groups are able to rotate in solution and the 1,2-acetonide is rigid, a nucleophilic attack from the Si-face should be preferred.

The donor-acceptor distance between O3 and the benzylic carbon is 3.387 (3) Å and is therefore in the range of C—H···O hydrogen bonds. (Gatti et al., 2002) Furthermore, H5 is hydrogen bonded to O2 of an adjacent molecule with a donor-acceptor distance of 3.386 (3) Å. These weak intermolecular interactions lead to chains of molecules of I featuring a twofold screw symmetry along the crystallographic b axis (see Fig. 2).

Related literature top

For background to sugar-based oxime derivatives, see: Tronchet et al. (1979, 1981, 1989); Peri et al. (2004). For the synthesis, see: Plenkiewicz et al. (1974); Fernández-González & Alonso (2006). For ring puckering analysis, see: Cremer & Pople (1975). For C–H···O interactions, see: Gatti et al. (2002). For the synthesis of a reactant, see: Shing et al. (1996).

Experimental top

All substances were purchased from commercial suppliers and used without further purification. Pyridine was dried over molecular sieves 4 Å. 1,2:5,6-Di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose was obtained from 1,2:5,6-di-O-isopropylidene-α-D-glucose (Shing et al., 1996)

Melting points are given uncorrected and were determined with a Gallenkamp melting point apparatus. Mass spectra were measured on a Bruker Daltonics MicroTOF spectrometer. Optical rotations were determined using a Perkin-Elmer 241 polarimeter with a path length of 1 dm (Concentrations are given in g/100 ml.). ¹H NMR, ¹³C NMR, ¹H,¹H COSY and ¹H,¹³C HSQC experiments were carried out on a Bruker 400 MHz s pectrometer. Chemical shifts are referenced for ¹H to CHCl₃ at 7.26 p.p.m. and for ¹³C to CDCl₃ at 77.03 p.p.m.. Multiplicities are quoted as singlet (s), doublet (d), doublet of doublets (dd), doublet of doublet of doublets (ddd) and multiplet (m). Coupling constants J are determined from zero-filled, resolution enhanced spectra.

(Z)-1,2:5,6-di-O-isopropylidene-α-D-ribo-hexofuranos-3- ulose O-benzyloxime (I): 1,2:5,6-Di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose (2.96 g, 11.5 mmol) was dissolved in pyridine (20 ml). After addition of O-benzylhydroxylamine hydrochloride (2.75 g, 17.2 mmol) the mixture was stirred at room temperature under nitrogen. After 26 h, TLC (CH₂Cl₂/ethyl acetate, 20:1) showed conversion of the starting material (R_f = 1/5) to a major product (R_f = 1/2). The mixture was concentrated in vacuo. The resulting white solid was dissolved in CH₂Cl₂/ethyl acetate. The organic phase was washed three times with water, dried over Na₂SO₄, filtered and concentrated in vacuo. Recrystallization from pentane/ethyl acetate (2:1) at 246 K gave (Z)-1,2:5,6-di-O-isopropylidene-α-D-ribo-hexofuranos-3- ulose O-benzyloxime (I) as colourless crystals. After filtration the product was dried in vacuo at 298 K. Yield: 3.10 g (74%). Single crystals suitable for X-ray determination were obtained after one week of gas diffusion of pentane into a solution of I (20 mg, 0.06 mmol) in ethyl acetate (0.5 ml). M.p. = 402–404 K (pentane/ethyl acetate). [α]_D²¹ = +201 (c = 1.0 in CHCl₃). ¹H NMR (400 MHz, CDCl₃, 298 K): 1.28, 1.33, 1.43 and 1.49 (4 s, 12H, H methyl), 3.77 (dd, ²J_66' = 8.3 Hz, ³J₆₅= 7.2 Hz, 1H, H6), 3.84 (dd, ³J_6'5= 6.8 Hz, 1H, H6'), 4.36 (ddd, ³J₅₄ = 2.6 Hz, 1H, H5), 4.84 (dd, ⁴J₄₂= 1.3 Hz, 1H, H4), 5.16 (dd, 1H, H2), 5.20 (2H, H10 and H10'), 5.95 (d, ³J₁₂ = 4.4 Hz, 1H, H1), 7.29–7.36 (m, 5H, H Ph) p.p.m.. ¹³C NMR (100 MHz, CDCl₃, 298 K): 25.5, 26.0, 27.3 and 27.4 (4 × q, C8, C9, C18 and C19), 64.2 (t, C6), 74.8 (d, C2), 76.9 (× 2) and 77.0 (2 × d and 1 × t, C4, C5 and C10), 104.8 (d, C1), 109.8 and 113.7 (2 × s, C7 and C17), 128.0, 128.2, 128.4, 137.6 and 157.0 (2 × s and 5 × d, C3 and C Ph) p.p.m.. ESI-HRMS: m/z calculated for C₁₉H₂₅NO₆ (MNa⁺) 386.1574, found 386.1579. C₁₉H₂₅NO₆ (363.40 g mol^-1): calculated C 62.80, H 6.93, N 3.85%; found C 63.08, H 7.45, N 3.89%.

Computing details top

Data collection: EXPOSE in IPDS Software (Stoe & Cie, 1997); cell refinement: CELL in IPDS Software (Stoe & Cie, 1997); data reduction: INTEGRATE in IPDS Software (Stoe & Cie, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1990); software used to prepare material for publication: PLATON (Spek, 2009), XP (Siemens, 1990) and SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular structure of the title compound (I) with displacement ellipsoids at 30% probability and atom-numbering scheme.
	Fig. 2. Molecules of (I) linked by C–H···O interactions resulting in chains with twofold screw symmetry along the crystallographic b axis.

(Z)-1,2:5,6-Di-O-isopropylidene-α-D-ribo- hexofuranos-3-ulose O-benzyloxime top

Crystal data top

C₁₉H₂₅NO₆	F(000) = 388
M_r = 363.40	D_x = 1.249 Mg m⁻³
Monoclinic, P2₁	Melting point: 403(1) K
Hall symbol: P 2yb	Mo Kα radiation, λ = 0.71073 Å
a = 11.8012 (12) Å	Cell parameters from 1353 reflections
b = 6.0019 (5) Å	θ = 1.9–28.2°
c = 13.7021 (11) Å	µ = 0.09 mm⁻¹
β = 95.122 (11)°	T = 293 K
V = 966.64 (15) Å³	Prism, colourless
Z = 2	0.30 × 0.05 × 0.04 mm

Data collection top

Stoe IPDS diffractometer	2023 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.104
Graphite monochromator	θ_max = 28.2°, θ_min = 3.0°
Detector resolution: 6.0 pixels mm^-1	h = −15→15
ϕ scans	k = −7→7
9449 measured reflections	l = −18→17
2558 independent 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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.131	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0808P)²] where P = (F_o² + 2F_c²)/3
2558 reflections	(Δ/σ)_max < 0.001
235 parameters	Δρ_max = 0.31 e Å⁻³
1 restraint	Δρ_min = −0.29 e Å⁻³

Crystal data top

C₁₉H₂₅NO₆	V = 966.64 (15) Å³
M_r = 363.40	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 11.8012 (12) Å	µ = 0.09 mm⁻¹
b = 6.0019 (5) Å	T = 293 K
c = 13.7021 (11) Å	0.30 × 0.05 × 0.04 mm
β = 95.122 (11)°

Data collection top

Stoe IPDS diffractometer	2023 reflections with I > 2σ(I)
9449 measured reflections	R_int = 0.104
2558 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	1 restraint
wR(F²) = 0.131	H-atom parameters constrained
S = 0.99	Δρ_max = 0.31 e Å⁻³
2558 reflections	Δρ_min = −0.29 e Å⁻³
235 parameters

Special details top

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 > 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

	x	y	z	U_iso*/U_eq
N1	−0.06053 (17)	0.2232 (4)	0.27810 (14)	0.0389 (4)
O1	0.02900 (13)	0.5554 (3)	0.09073 (11)	0.0389 (4)
O2	0.11981 (15)	0.8375 (3)	0.18283 (13)	0.0445 (4)
O3	0.07981 (16)	0.6561 (4)	0.32044 (12)	0.0510 (5)
O4	−0.06093 (18)	0.2884 (3)	0.37689 (13)	0.0477 (4)
O5	−0.21517 (14)	0.5609 (3)	0.09506 (14)	0.0469 (4)
O6	−0.34050 (19)	0.2785 (5)	0.0706 (3)	0.1008 (12)
C1	0.01554 (19)	0.7319 (4)	0.15833 (17)	0.0371 (5)
H1	−0.0423	0.8385	0.1321	0.044*
C2	−0.01695 (19)	0.6276 (4)	0.25278 (17)	0.0363 (5)
H2	−0.0841	0.7001	0.2758	0.044*
C3	−0.04108 (17)	0.3891 (4)	0.22521 (16)	0.0325 (4)
C4	−0.03742 (18)	0.3679 (4)	0.11580 (16)	0.0334 (4)
H4	0.0012	0.2294	0.1004	0.040*
C5	−0.15390 (19)	0.3778 (4)	0.05929 (18)	0.0384 (5)
H5	−0.1455	0.3985	−0.0106	0.046*
C6	−0.2320 (2)	0.1834 (5)	0.0731 (3)	0.0554 (7)
H6A	−0.2283	0.0754	0.0208	0.067*
H6B	−0.2119	0.1103	0.1354	0.067*
C7	0.1722 (2)	0.7382 (5)	0.27004 (19)	0.0457 (6)
C8	0.2295 (3)	0.9206 (6)	0.3320 (3)	0.0664 (9)
H8A	0.2656	0.8576	0.3913	0.100*
H8B	0.1738	1.0280	0.3479	0.100*
H8C	0.2857	0.9922	0.2963	0.100*
C9	0.2493 (3)	0.5495 (8)	0.2465 (3)	0.0773 (10)
H9A	0.2837	0.4860	0.3063	0.116*
H9B	0.3076	0.6048	0.2084	0.116*
H9C	0.2058	0.4375	0.2099	0.116*
C10	−0.0865 (2)	0.0973 (5)	0.43327 (18)	0.0494 (6)
H10A	−0.0655	0.1285	0.5020	0.059*
H10B	−0.0403	−0.0266	0.4146	0.059*
C11	−0.2096 (2)	0.0296 (5)	0.42074 (18)	0.0452 (6)
C12	−0.2392 (3)	−0.1738 (7)	0.4566 (4)	0.0787 (12)
H12	−0.1830	−0.2674	0.4856	0.094*
C13	−0.3520 (3)	−0.2411 (8)	0.4502 (4)	0.0966 (15)
H13	−0.3711	−0.3789	0.4751	0.116*
C14	−0.4337 (3)	−0.1078 (10)	0.4081 (4)	0.0921 (14)
H14	−0.5095	−0.1515	0.4058	0.111*
C15	−0.4060 (3)	0.0900 (11)	0.3690 (5)	0.114 (2)
H15	−0.4623	0.1795	0.3376	0.137*
C16	−0.2925 (3)	0.1590 (7)	0.3761 (3)	0.0835 (12)
H16	−0.2738	0.2956	0.3498	0.100*
C17	−0.3326 (2)	0.5127 (6)	0.0709 (3)	0.0613 (8)
C18	−0.3984 (3)	0.6133 (11)	0.1487 (4)	0.1084 (18)
H18A	−0.3931	0.7728	0.1458	0.163*
H18B	−0.3674	0.5623	0.2119	0.163*
H18C	−0.4767	0.5693	0.1380	0.163*
C19	−0.3701 (3)	0.5986 (8)	−0.0303 (3)	0.0872 (12)
H19A	−0.3649	0.7582	−0.0307	0.131*
H19B	−0.4473	0.5545	−0.0481	0.131*
H19C	−0.3218	0.5378	−0.0765	0.131*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0444 (10)	0.0412 (10)	0.0313 (9)	−0.0039 (8)	0.0040 (8)	−0.0003 (8)
O1	0.0417 (8)	0.0452 (9)	0.0306 (7)	−0.0071 (7)	0.0083 (6)	0.0006 (7)
O2	0.0443 (9)	0.0466 (10)	0.0421 (9)	−0.0176 (7)	0.0019 (7)	0.0041 (8)
O3	0.0495 (9)	0.0706 (12)	0.0317 (8)	−0.0259 (9)	−0.0027 (7)	0.0008 (8)
O4	0.0652 (11)	0.0476 (9)	0.0312 (8)	−0.0141 (8)	0.0090 (8)	−0.0014 (7)
O5	0.0343 (8)	0.0513 (10)	0.0536 (10)	0.0019 (8)	−0.0047 (7)	−0.0090 (9)
O6	0.0367 (10)	0.0663 (15)	0.199 (4)	−0.0063 (11)	0.0061 (15)	0.0190 (19)
C1	0.0360 (10)	0.0364 (10)	0.0383 (12)	−0.0056 (9)	0.0007 (9)	0.0028 (10)
C2	0.0349 (10)	0.0418 (11)	0.0323 (11)	−0.0041 (9)	0.0042 (8)	−0.0050 (9)
C3	0.0275 (9)	0.0375 (10)	0.0324 (11)	0.0007 (8)	0.0023 (8)	−0.0014 (9)
C4	0.0361 (10)	0.0327 (10)	0.0317 (10)	−0.0012 (8)	0.0050 (8)	−0.0017 (9)
C5	0.0398 (11)	0.0413 (11)	0.0335 (11)	−0.0010 (10)	−0.0002 (9)	−0.0070 (10)
C6	0.0411 (12)	0.0512 (15)	0.0721 (19)	−0.0080 (12)	−0.0050 (13)	−0.0109 (14)
C7	0.0400 (12)	0.0549 (14)	0.0416 (13)	−0.0101 (11)	0.0001 (10)	0.0039 (12)
C8	0.0580 (16)	0.077 (2)	0.0614 (19)	−0.0270 (16)	−0.0088 (15)	−0.0039 (16)
C9	0.0561 (17)	0.089 (3)	0.086 (2)	0.0134 (19)	−0.0004 (17)	0.001 (2)
C10	0.0557 (14)	0.0593 (16)	0.0330 (12)	−0.0121 (13)	0.0026 (10)	0.0076 (12)
C11	0.0511 (13)	0.0508 (14)	0.0350 (11)	−0.0015 (11)	0.0108 (10)	0.0022 (11)
C12	0.0552 (17)	0.073 (2)	0.108 (3)	−0.0078 (16)	0.0104 (18)	0.038 (2)
C13	0.061 (2)	0.089 (3)	0.141 (4)	−0.019 (2)	0.015 (2)	0.039 (3)
C14	0.0490 (17)	0.114 (3)	0.115 (4)	−0.004 (2)	0.016 (2)	0.008 (3)
C15	0.0470 (18)	0.126 (4)	0.169 (5)	0.019 (2)	0.009 (2)	0.051 (4)
C16	0.0572 (18)	0.075 (2)	0.119 (3)	0.0096 (17)	0.017 (2)	0.036 (2)
C17	0.0320 (11)	0.0644 (18)	0.086 (2)	0.0029 (12)	−0.0023 (12)	0.0015 (17)
C18	0.060 (2)	0.151 (5)	0.118 (4)	0.038 (3)	0.028 (2)	0.013 (4)
C19	0.0623 (18)	0.092 (3)	0.100 (3)	0.007 (2)	−0.0366 (19)	0.001 (2)

Geometric parameters (Å, º) top

N1—C3	1.265 (3)	C8—H8B	0.9600
N1—O4	1.410 (3)	C8—H8C	0.9600
O1—C1	1.425 (3)	C9—H9A	0.9600
O1—C4	1.431 (3)	C9—H9B	0.9600
O2—C1	1.398 (3)	C9—H9C	0.9600
O2—C7	1.426 (3)	C10—C11	1.504 (4)
O3—C2	1.416 (3)	C10—H10A	0.9700
O3—C7	1.429 (3)	C10—H10B	0.9700
O4—C10	1.430 (3)	C11—C16	1.352 (4)
O5—C17	1.426 (3)	C11—C12	1.373 (5)
O5—C5	1.426 (3)	C12—C13	1.386 (5)
O6—C6	1.400 (4)	C12—H12	0.9300
O6—C17	1.409 (4)	C13—C14	1.343 (7)
C1—C2	1.518 (3)	C13—H13	0.9300
C1—H1	0.9800	C14—C15	1.354 (7)
C2—C3	1.501 (3)	C14—H14	0.9300
C2—H2	0.9800	C15—C16	1.397 (6)
C3—C4	1.509 (3)	C15—H15	0.9300
C4—C5	1.517 (3)	C16—H16	0.9300
C4—H4	0.9800	C17—C18	1.501 (6)
C5—C6	1.509 (4)	C17—C19	1.508 (5)
C5—H5	0.9800	C18—H18A	0.9600
C6—H6A	0.9700	C18—H18B	0.9600
C6—H6B	0.9700	C18—H18C	0.9600
C7—C9	1.506 (5)	C19—H19A	0.9600
C7—C8	1.508 (4)	C19—H19B	0.9600
C8—H8A	0.9600	C19—H19C	0.9600

C3—N1—O4	110.36 (19)	H8A—C8—H8C	109.5
C1—O1—C4	109.48 (16)	H8B—C8—H8C	109.5
C1—O2—C7	108.55 (18)	C7—C9—H9A	109.5
C2—O3—C7	109.31 (17)	C7—C9—H9B	109.5
N1—O4—C10	108.36 (18)	H9A—C9—H9B	109.5
C17—O5—C5	106.0 (2)	C7—C9—H9C	109.5
C6—O6—C17	110.3 (2)	H9A—C9—H9C	109.5
O2—C1—O1	110.25 (18)	H9B—C9—H9C	109.5
O2—C1—C2	105.44 (18)	O4—C10—C11	113.8 (2)
O1—C1—C2	107.37 (19)	O4—C10—H10A	108.8
O2—C1—H1	111.2	C11—C10—H10A	108.8
O1—C1—H1	111.2	O4—C10—H10B	108.8
C2—C1—H1	111.2	C11—C10—H10B	108.8
O3—C2—C3	113.8 (2)	H10A—C10—H10B	107.7
O3—C2—C1	104.96 (18)	C16—C11—C12	118.4 (3)
C3—C2—C1	103.64 (19)	C16—C11—C10	123.3 (3)
O3—C2—H2	111.3	C12—C11—C10	118.3 (3)
C3—C2—H2	111.3	C11—C12—C13	120.6 (4)
C1—C2—H2	111.3	C11—C12—H12	119.7
N1—C3—C2	130.3 (2)	C13—C12—H12	119.7
N1—C3—C4	121.7 (2)	C14—C13—C12	120.2 (4)
C2—C3—C4	107.98 (19)	C14—C13—H13	119.9
O1—C4—C3	103.72 (17)	C12—C13—H13	119.9
O1—C4—C5	109.72 (18)	C13—C14—C15	120.2 (4)
C3—C4—C5	113.50 (18)	C13—C14—H14	119.9
O1—C4—H4	109.9	C15—C14—H14	119.9
C3—C4—H4	109.9	C14—C15—C16	119.8 (4)
C5—C4—H4	109.9	C14—C15—H15	120.1
O5—C5—C6	102.63 (19)	C16—C15—H15	120.1
O5—C5—C4	108.59 (18)	C11—C16—C15	120.8 (4)
C6—C5—C4	116.2 (2)	C11—C16—H16	119.6
O5—C5—H5	109.7	C15—C16—H16	119.6
C6—C5—H5	109.7	O6—C17—O5	105.4 (2)
C4—C5—H5	109.7	O6—C17—C18	111.4 (4)
O6—C6—C5	104.4 (2)	O5—C17—C18	107.9 (3)
O6—C6—H6A	110.9	O6—C17—C19	109.0 (4)
C5—C6—H6A	110.9	O5—C17—C19	110.1 (3)
O6—C6—H6B	110.9	C18—C17—C19	112.8 (3)
C5—C6—H6B	110.9	C17—C18—H18A	109.5
H6A—C6—H6B	108.9	C17—C18—H18B	109.5
O2—C7—O3	104.90 (19)	H18A—C18—H18B	109.5
O2—C7—C9	111.1 (3)	C17—C18—H18C	109.5
O3—C7—C9	110.2 (3)	H18A—C18—H18C	109.5
O2—C7—C8	107.9 (2)	H18B—C18—H18C	109.5
O3—C7—C8	107.6 (2)	C17—C19—H19A	109.5
C9—C7—C8	114.6 (3)	C17—C19—H19B	109.5
C7—C8—H8A	109.5	H19A—C19—H19B	109.5
C7—C8—H8B	109.5	C17—C19—H19C	109.5
H8A—C8—H8B	109.5	H19A—C19—H19C	109.5
C7—C8—H8C	109.5	H19B—C19—H19C	109.5

C3—N1—O4—C10	178.3 (2)	C3—C4—C5—C6	−68.1 (3)
C7—O2—C1—O1	−93.8 (2)	C17—O6—C6—C5	−8.4 (4)
C7—O2—C1—C2	21.8 (3)	O5—C5—C6—O6	25.7 (3)
C4—O1—C1—O2	139.51 (18)	C4—C5—C6—O6	144.0 (3)
C4—O1—C1—C2	25.1 (2)	C1—O2—C7—O3	−27.2 (3)
C7—O3—C2—C3	104.1 (2)	C1—O2—C7—C9	91.9 (3)
C7—O3—C2—C1	−8.6 (3)	C1—O2—C7—C8	−141.6 (2)
O2—C1—C2—O3	−8.0 (3)	C2—O3—C7—O2	21.7 (3)
O1—C1—C2—O3	109.5 (2)	C2—O3—C7—C9	−98.0 (3)
O2—C1—C2—C3	−127.70 (19)	C2—O3—C7—C8	136.4 (2)
O1—C1—C2—C3	−10.1 (2)	N1—O4—C10—C11	−74.9 (3)
O4—N1—C3—C2	1.8 (3)	O4—C10—C11—C16	−12.1 (4)
O4—N1—C3—C4	−179.14 (19)	O4—C10—C11—C12	168.0 (3)
O3—C2—C3—N1	58.5 (3)	C16—C11—C12—C13	−2.2 (7)
C1—C2—C3—N1	172.0 (2)	C10—C11—C12—C13	177.7 (4)
O3—C2—C3—C4	−120.6 (2)	C11—C12—C13—C14	0.4 (8)
C1—C2—C3—C4	−7.2 (2)	C12—C13—C14—C15	2.0 (9)
C1—O1—C4—C3	−28.9 (2)	C13—C14—C15—C16	−2.5 (9)
C1—O1—C4—C5	92.7 (2)	C12—C11—C16—C15	1.7 (7)
N1—C3—C4—O1	−157.54 (19)	C10—C11—C16—C15	−178.2 (5)
C2—C3—C4—O1	21.7 (2)	C14—C15—C16—C11	0.6 (9)
N1—C3—C4—C5	83.5 (3)	C6—O6—C17—O5	−12.4 (5)
C2—C3—C4—C5	−97.3 (2)	C6—O6—C17—C18	−129.1 (4)
C17—O5—C5—C6	−33.8 (3)	C6—O6—C17—C19	105.8 (4)
C17—O5—C5—C4	−157.3 (2)	C5—O5—C17—O6	29.4 (4)
O1—C4—C5—O5	−68.6 (2)	C5—O5—C17—C18	148.5 (3)
C3—C4—C5—O5	46.9 (3)	C5—O5—C17—C19	−88.0 (3)
O1—C4—C5—C6	176.4 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.98	2.43	3.386 (3)	164
C10—H10A···O3ⁱⁱ	0.97	2.46	3.387 (3)	160

Symmetry codes: (i) −x, y−1/2, −z; (ii) −x, y−1/2, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₉H₂₅NO₆
M_r	363.40
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	293
a, b, c (Å)	11.8012 (12), 6.0019 (5), 13.7021 (11)
β (°)	95.122 (11)
V (Å³)	966.64 (15)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.30 × 0.05 × 0.04

Data collection
Diffractometer	Stoe IPDS diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9449, 2558, 2023
R_int	0.104
(sin θ/λ)_max (Å⁻¹)	0.665

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.131, 0.99
No. of reflections	2558
No. of parameters	235
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.31, −0.29

Computer programs: EXPOSE in IPDS Software (Stoe & Cie, 1997), CELL in IPDS Software (Stoe & Cie, 1997), INTEGRATE in IPDS Software (Stoe & Cie, 1997), SHELXS97 (Sheldrick, 2008), PLATON (Spek, 2009), XP (Siemens, 1990) and SHELXL97 (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.98	2.43	3.386 (3)	164
C10—H10A···O3ⁱⁱ	0.97	2.46	3.387 (3)	160

Symmetry codes: (i) −x, y−1/2, −z; (ii) −x, y−1/2, −z+1.

Acknowledgements

This work was supported by the Carl Trygger Foundation and the Swedish Research Council (VR).

References

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