organic compounds
(1S)-1,2-O-Benzylidene-α-D-glucurono-6,3-lactone
aDepartment of Organic Chemistry, Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, England, bDextra Laboratories Ltd, Science and Technology Centre, Whiteknights Road, Reading RG6 6BZ, England, and cDepartment of Chemical Crystallography, Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, England
*Correspondence e-mail: sarah.jenkinson@chem.ox.ac.uk
X-ray crystallographic analysis has established that the major product from the protection of D-glucoronolactone with benzaldehyde is (1S)-1,2-O-benzylidene-α-D-glucurono-6,3-lactone, C13H12O6, rather than the R epimer. The exists as O—H⋯O hydrogen-bonded chains of molecules lying parallel to the a axis. The was determined by the use of D-glucuronolactone as the starting material.
Related literature
For related literature on the synthesis of protected D-glucuronolactone, see: Sheldrick et al. (1983); Macher et al. (1979); Shah (1969). For literature related to the use of acetonide-protected D-glucuronolactone as an intermediate in the synthesis of (a) other sugars, see: Bleriot et al. (1997); Dax et al. (1991); Ke et al. (2003); Masaguer et al. (1997); (b) imino sugars, see: Dax et al. (1990); (c) sugar amino acids, see: Bashyal et al. (1986, 1987); (d) many other bioactive targets, see: Kitahara et al. (1974); Austin et al. (1987); Witty et al. (1990); Shing & Tsui (1992); Yoda et al. (2002). For the original NMR studies on benzylidene-protected glucoronolactone, see Csuk et al. (1984).
Experimental
Crystal data
|
Refinement
|
Data collection: COLLECT (Nonius, 2001); cell DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS.
Supporting information
10.1107/S1600536809002876/lh2760sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809002876/lh2760Isup2.hkl
The title compound was recrystallized by vapour diffusion from a mixture of ethyl acetate and cyclohexane: m.p. 419.5–421.5 K; [α]D20 +67 (c, 1.0 in acetone) (Macher et al., 1979).
In the absence of significant
Friedel pairs were merged and the was assigned from the starting material.The H atoms were all located in a difference map, but those attached to C atoms were repositioned geometrically. The H atoms were initially refined with soft restraints on the bond lengths and angles to regularize their geometry (C—H in the range 0.93–0.98, O—H = 0.82 Å) and Uiso(H) (in the range 1.2–1.5 times Ueq of the parent atom), after which the positions were refined with riding constraints.
Data collection: COLLECT (Nonius, 2001); cell
DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).C13H12O6 | F(000) = 276 |
Mr = 264.23 | Dx = 1.504 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 1368 reflections |
a = 5.6329 (1) Å | θ = 5–27° |
b = 7.8943 (2) Å | µ = 0.12 mm−1 |
c = 13.3182 (3) Å | T = 150 K |
β = 99.9545 (9)° | Plate, colourless |
V = 583.32 (2) Å3 | 0.60 × 0.50 × 0.30 mm |
Z = 2 |
Nonius KappaCCD area-detector diffractometer | 1341 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
ω scans | θmax = 27.5°, θmin = 5.2° |
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) | h = −7→7 |
Tmin = 0.88, Tmax = 0.96 | k = −10→10 |
8275 measured reflections | l = −17→17 |
1418 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.027 | H-atom parameters constrained |
wR(F2) = 0.068 | Method = modified Sheldrick w = 1/[σ2(F2) + (0.04P)2 + 0.13P], where P = [max(Fo2,0) + 2Fc2]/3 |
S = 0.96 | (Δ/σ)max = 0.009 |
1418 reflections | Δρmax = 0.20 e Å−3 |
172 parameters | Δρmin = −0.18 e Å−3 |
1 restraint |
C13H12O6 | V = 583.32 (2) Å3 |
Mr = 264.23 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 5.6329 (1) Å | µ = 0.12 mm−1 |
b = 7.8943 (2) Å | T = 150 K |
c = 13.3182 (3) Å | 0.60 × 0.50 × 0.30 mm |
β = 99.9545 (9)° |
Nonius KappaCCD area-detector diffractometer | 1418 independent reflections |
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) | 1341 reflections with I > 2σ(I) |
Tmin = 0.88, Tmax = 0.96 | Rint = 0.022 |
8275 measured reflections |
R[F2 > 2σ(F2)] = 0.027 | 1 restraint |
wR(F2) = 0.068 | H-atom parameters constrained |
S = 0.96 | Δρmax = 0.20 e Å−3 |
1418 reflections | Δρmin = −0.18 e Å−3 |
172 parameters |
x | y | z | Uiso*/Ueq | ||
O1 | 1.1555 (2) | 0.28908 (18) | 1.09521 (9) | 0.0317 | |
C2 | 1.0013 (3) | 0.2487 (3) | 1.02461 (12) | 0.0257 | |
O3 | 1.04981 (19) | 0.2312 (2) | 0.92986 (9) | 0.0296 | |
C4 | 0.8321 (3) | 0.1868 (2) | 0.85789 (12) | 0.0263 | |
C5 | 0.6246 (3) | 0.2272 (2) | 0.91452 (12) | 0.0246 | |
C6 | 0.7382 (3) | 0.2089 (2) | 1.02587 (12) | 0.0259 | |
O7 | 0.6540 (2) | 0.3147 (2) | 1.09703 (9) | 0.0334 | |
O8 | 0.5720 (2) | 0.40215 (18) | 0.89088 (9) | 0.0285 | |
C9 | 0.6089 (3) | 0.4347 (2) | 0.79011 (12) | 0.0265 | |
C10 | 0.8011 (3) | 0.3081 (2) | 0.76761 (12) | 0.0267 | |
O11 | 0.6942 (2) | 0.2266 (2) | 0.67619 (9) | 0.0323 | |
C12 | 0.4413 (3) | 0.2413 (2) | 0.66815 (12) | 0.0269 | |
O13 | 0.4052 (2) | 0.40025 (19) | 0.71549 (9) | 0.0307 | |
C14 | 0.3210 (3) | 0.2382 (2) | 0.55862 (12) | 0.0266 | |
C15 | 0.1004 (3) | 0.1573 (3) | 0.53152 (14) | 0.0320 | |
C16 | −0.0149 (3) | 0.1563 (3) | 0.43042 (15) | 0.0379 | |
C17 | 0.0921 (3) | 0.2338 (3) | 0.35636 (14) | 0.0374 | |
C18 | 0.3143 (3) | 0.3125 (3) | 0.38315 (14) | 0.0368 | |
C19 | 0.4288 (3) | 0.3166 (3) | 0.48437 (14) | 0.0321 | |
H41 | 0.8338 | 0.0667 | 0.8363 | 0.0325* | |
H51 | 0.4805 | 0.1554 | 0.8912 | 0.0314* | |
H61 | 0.7293 | 0.0846 | 1.0439 | 0.0312* | |
H91 | 0.6542 | 0.5570 | 0.7843 | 0.0323* | |
H101 | 0.9551 | 0.3623 | 0.7612 | 0.0324* | |
H121 | 0.3793 | 0.1500 | 0.7071 | 0.0326* | |
H151 | 0.0235 | 0.1040 | 0.5830 | 0.0404* | |
H161 | −0.1724 | 0.1016 | 0.4108 | 0.0448* | |
H171 | 0.0114 | 0.2344 | 0.2852 | 0.0453* | |
H181 | 0.3876 | 0.3631 | 0.3302 | 0.0450* | |
H191 | 0.5853 | 0.3725 | 0.5058 | 0.0382* | |
H71 | 0.5030 | 0.2905 | 1.0901 | 0.0522* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0237 (6) | 0.0355 (8) | 0.0344 (6) | 0.0018 (5) | 0.0009 (5) | −0.0001 (5) |
C2 | 0.0234 (7) | 0.0216 (7) | 0.0319 (8) | 0.0030 (7) | 0.0044 (6) | 0.0031 (7) |
O3 | 0.0193 (5) | 0.0384 (7) | 0.0316 (6) | 0.0026 (5) | 0.0051 (4) | 0.0001 (6) |
C4 | 0.0213 (7) | 0.0265 (8) | 0.0306 (8) | 0.0011 (6) | 0.0036 (6) | −0.0021 (7) |
C5 | 0.0209 (7) | 0.0227 (8) | 0.0306 (8) | −0.0016 (7) | 0.0058 (6) | −0.0001 (7) |
C6 | 0.0233 (7) | 0.0256 (9) | 0.0295 (8) | −0.0013 (7) | 0.0059 (6) | 0.0014 (7) |
O7 | 0.0262 (6) | 0.0428 (8) | 0.0325 (6) | −0.0009 (6) | 0.0088 (5) | −0.0056 (6) |
O8 | 0.0309 (6) | 0.0268 (6) | 0.0286 (6) | 0.0060 (6) | 0.0077 (5) | 0.0009 (5) |
C9 | 0.0291 (8) | 0.0228 (8) | 0.0276 (8) | 0.0000 (7) | 0.0050 (6) | −0.0006 (6) |
C10 | 0.0226 (7) | 0.0295 (9) | 0.0286 (8) | −0.0018 (7) | 0.0064 (6) | −0.0018 (7) |
O11 | 0.0252 (5) | 0.0416 (7) | 0.0302 (6) | 0.0068 (6) | 0.0047 (4) | −0.0076 (6) |
C12 | 0.0251 (7) | 0.0240 (8) | 0.0319 (8) | 0.0009 (7) | 0.0061 (6) | −0.0012 (7) |
O13 | 0.0285 (6) | 0.0316 (7) | 0.0305 (6) | 0.0082 (6) | 0.0010 (5) | −0.0051 (5) |
C14 | 0.0267 (7) | 0.0231 (8) | 0.0302 (8) | 0.0019 (7) | 0.0056 (6) | −0.0024 (7) |
C15 | 0.0291 (8) | 0.0301 (9) | 0.0380 (9) | −0.0033 (8) | 0.0095 (7) | −0.0071 (8) |
C16 | 0.0298 (9) | 0.0393 (11) | 0.0432 (11) | −0.0038 (8) | 0.0021 (8) | −0.0154 (9) |
C17 | 0.0419 (10) | 0.0367 (10) | 0.0319 (8) | 0.0061 (9) | 0.0014 (7) | −0.0079 (9) |
C18 | 0.0423 (10) | 0.0343 (10) | 0.0344 (9) | 0.0016 (9) | 0.0083 (8) | 0.0017 (8) |
C19 | 0.0314 (8) | 0.0291 (9) | 0.0363 (9) | −0.0040 (8) | 0.0068 (7) | 0.0011 (8) |
O1—C2 | 1.207 (2) | C10—O11 | 1.416 (2) |
C2—O3 | 1.344 (2) | C10—H101 | 0.984 |
C2—C6 | 1.518 (2) | O11—C12 | 1.4148 (19) |
O3—C4 | 1.4628 (19) | C12—O13 | 1.435 (2) |
C4—C5 | 1.530 (2) | C12—C14 | 1.499 (2) |
C4—C10 | 1.524 (2) | C12—H121 | 0.987 |
C4—H41 | 0.991 | C14—C15 | 1.388 (2) |
C5—C6 | 1.517 (2) | C14—C19 | 1.392 (3) |
C5—O8 | 1.436 (2) | C15—C16 | 1.390 (3) |
C5—H51 | 0.995 | C15—H151 | 0.969 |
C6—O7 | 1.406 (2) | C16—C17 | 1.384 (3) |
C6—H61 | 1.014 | C16—H161 | 0.981 |
O7—H71 | 0.861 | C17—C18 | 1.388 (3) |
O8—C9 | 1.417 (2) | C17—H171 | 0.977 |
C9—C10 | 1.540 (2) | C18—C19 | 1.390 (3) |
C9—O13 | 1.4088 (19) | C18—H181 | 0.963 |
C9—H91 | 1.005 | C19—H191 | 0.983 |
O1—C2—O3 | 121.52 (15) | C9—C10—O11 | 104.69 (13) |
O1—C2—C6 | 128.19 (15) | C4—C10—O11 | 111.49 (15) |
O3—C2—C6 | 110.28 (13) | C9—C10—H101 | 113.3 |
C2—O3—C4 | 110.88 (12) | C4—C10—H101 | 111.0 |
O3—C4—C5 | 104.62 (13) | O11—C10—H101 | 111.9 |
O3—C4—C10 | 109.58 (14) | C10—O11—C12 | 107.49 (12) |
C5—C4—C10 | 105.37 (13) | O11—C12—O13 | 104.83 (13) |
O3—C4—H41 | 111.7 | O11—C12—C14 | 110.64 (13) |
C5—C4—H41 | 112.9 | O13—C12—C14 | 111.54 (15) |
C10—C4—H41 | 112.2 | O11—C12—H121 | 110.1 |
C4—C5—C6 | 103.48 (12) | O13—C12—H121 | 108.5 |
C4—C5—O8 | 103.80 (13) | C14—C12—H121 | 111.0 |
C6—C5—O8 | 109.98 (14) | C12—O13—C9 | 108.59 (12) |
C4—C5—H51 | 112.3 | C12—C14—C15 | 119.63 (16) |
C6—C5—H51 | 115.8 | C12—C14—C19 | 120.33 (15) |
O8—C5—H51 | 110.7 | C15—C14—C19 | 120.04 (16) |
C2—C6—C5 | 102.55 (12) | C14—C15—C16 | 120.10 (18) |
C2—C6—O7 | 109.20 (14) | C14—C15—H151 | 120.4 |
C5—C6—O7 | 117.93 (14) | C16—C15—H151 | 119.5 |
C2—C6—H61 | 106.9 | C15—C16—C17 | 119.99 (17) |
C5—C6—H61 | 107.1 | C15—C16—H161 | 120.7 |
O7—C6—H61 | 112.2 | C17—C16—H161 | 119.3 |
C6—O7—H71 | 103.8 | C16—C17—C18 | 119.95 (17) |
C5—O8—C9 | 108.88 (13) | C16—C17—H171 | 120.4 |
O8—C9—C10 | 106.84 (14) | C18—C17—H171 | 119.6 |
O8—C9—O13 | 113.45 (14) | C17—C18—C19 | 120.40 (18) |
C10—C9—O13 | 104.58 (13) | C17—C18—H181 | 118.6 |
O8—C9—H91 | 109.2 | C19—C18—H181 | 121.0 |
C10—C9—H91 | 114.3 | C14—C19—C18 | 119.51 (17) |
O13—C9—H91 | 108.5 | C14—C19—H191 | 118.2 |
C9—C10—C4 | 104.06 (13) | C18—C19—H191 | 122.3 |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H41···O1i | 0.99 | 2.37 | 3.200 (3) | 141 |
C6—H61···O8ii | 1.01 | 2.49 | 3.289 (3) | 135 |
C9—H91···O1iii | 1.01 | 2.55 | 3.349 (3) | 137 |
C15—H151···O11iv | 0.97 | 2.59 | 3.281 (3) | 128 |
C16—H161···O13v | 0.98 | 2.51 | 3.350 (3) | 143 |
O7—H71···O1iv | 0.86 | 1.97 | 2.811 (3) | 165 |
Symmetry codes: (i) −x+2, y−1/2, −z+2; (ii) −x+1, y−1/2, −z+2; (iii) −x+2, y+1/2, −z+2; (iv) x−1, y, z; (v) −x, y−1/2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C13H12O6 |
Mr | 264.23 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 150 |
a, b, c (Å) | 5.6329 (1), 7.8943 (2), 13.3182 (3) |
β (°) | 99.9545 (9) |
V (Å3) | 583.32 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.12 |
Crystal size (mm) | 0.60 × 0.50 × 0.30 |
Data collection | |
Diffractometer | Nonius KappaCCD area-detector diffractometer |
Absorption correction | Multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) |
Tmin, Tmax | 0.88, 0.96 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8275, 1418, 1341 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.068, 0.96 |
No. of reflections | 1418 |
No. of parameters | 172 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.20, −0.18 |
Computer programs: COLLECT (Nonius, 2001), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), CAMERON (Watkin et al., 1996).
D—H···A | D—H | H···A | D···A | D—H···A |
O7—H71···O1i | 0.86 | 1.97 | 2.811 (3) | 165 |
Symmetry code: (i) x−1, y, z. |
Acknowledgements
The authors thank the Oxford University Crystallography Service for use of the instruments.
References
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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.
D-Glucuronolactone 3 (Fig. 1), the only cheaply availably uronic acid, reacts with acetone in the presence of an acid catalyst to form the acetonide 4 (Sheldrick et al., 1983). With only a single unprotected hydroxyl group, the lactone 4 provides convenient access to C-5 of D-glucose and has long been used as a versatile intermediate for the synthesis of other sugars (Bleriot et al., 1997; Dax et al., 1991; Ke et al., 2003; Masaguer et al., 1997), imino sugars (Dax et al., 1990), sugar amino acids (Bashyal et al., 1986, 1987) and many other bioactive targets (Kitahara et al., 1974; Austin et al., 1987; Witty et al., 1990; Shing & Tsui, 1992; Yoda et al., 2002). Reaction of 3 with benzaldehyde in the presence of zinc chloride gives a high yield of the benzylidene protected lactones in which the epimers are formed in a ratio of approximately 5:1 (Macher et al., 1979; Shah, 1969). The configuration of the benzylidene acetal has previously been investigated by NMR experiments which suggest that 1, which is the major product, has the 1,2(S)-configuration (Csuk et al., 1984). The crystallographic analysis confirms that this assignment is correct and that the major product is 1. Although as yet there have been no examples of the use of the benzylidene acetals 1 and 2 as synthetic intermediates, it is likely there will be cases where the use of a benzylidene group, which can be removed by hydrogenation, will have a significant advantage over the acetonide 4, where strong acid must be used to remove the protecting group.
The title compound (Fig. 2) exists as alternating layers of hydrogen bonded chains of molecules lying parallel to the a-axis (Fig. 3, Fig. 4). Only classical hydrogen bonding has been considered. The absolute configuration was determined by the use of D-glucuronolactone as the starting material.