6-De­oxy-α-l-talopyran­ose

Abstract

X-ray crystallography showed that the title compound, C₆H₁₂O₅, crystallizes in the α-pyran­ose form with the six-membered ring in a chair conformation. The crystal structure exists as a three-dimensional hydrogen-bonded network of mol­ecules with each mol­ecule acting as a donor and aceptor for four hydrogen bonds. The absolute configuration was determined by the use of l-fucose as starting material.

Related literature

For related literature, see: Beadle et al. (1992 ▶); Izumori (2002 ▶, 2006 ▶); Granstrom et al. (2004 ▶); Yoshihara et al. (2008 ▶).

Experimental

Crystal data

• C₆H₁₂O₅

• M _r = 164.16

• Orthorhombic,

• a = 6.4939 (3) Å

• b = 7.4874 (4) Å

• c = 14.8382 (8) Å

• V = 721.47 (6) ų

• Z = 4

• Mo Kα radiation

• μ = 0.13 mm⁻¹

• T = 150 K

• 0.25 × 0.25 × 0.02 mm

Data collection

• Nonius KappaCCD diffractometer

• Absorption correction: multi-scan DENZO/SCALEPACK (Otwinowski & Minor, 1997 ▶) T _min = 0.97, T _max = 1.00 (expected range = 0.967–0.997)

• 4390 measured reflections

• 968 independent reflections

• 863 reflections with I > 2.0σ(I)

• R _int = 0.037

Refinement

• R[F ² > 2σ(F ²)] = 0.029

• wR(F ²) = 0.072

• S = 1.03

• 968 reflections

• 100 parameters

• H-atom parameters constrained

• Δρ_max = 0.24 e Å⁻³

• Δρ_min = −0.21 e Å⁻³

Data collection: COLLECT (Nonius, 1997–2001 ▶).; cell refinement: 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.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O9—H7⋯O1i	0.81	2.04	2.818 (2)	162
O1—H8⋯O10	0.82	1.98	2.740 (2)	156
O10—H10⋯O9i	0.84	1.85	2.686 (2)	177
O11—H1⋯O4ii	0.87	1.94	2.812 (2)	177

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

The range of rare sugars that are now readily available has increased in recent years due to both chemical (Beadle et al., 1992) and biotechnological (Izumori, 2006; Izumori, 2002; Granstrom et al., 2004) advances. The methodology developed by Izumori et al. for the interconversion of tetroses, pentoses and hexoses by enzymatic oxidation, inversion at C3 with a single epimerase, and reduction to the aldose has been seen to be generally applicable for the 1-deoxy ketohexoses (Yoshihara et al., 2008) in large amounts in water.

The Izumoring method is demonstrated here with the synthesis of 6-deoxy-L-talose 3 from L-fucose 1(Fig. 1) by a series of isomerizations. Firstly, using D-arabinose isomerase, L-fucose was isomerized to 6-deoxy-L-tagatose 2 and then using L-rhamnose isomerase this was further isomerized to give 6-deoxy-L-talose 3.

6-Deoxy-L-talose crystallizes solely in the α-pyranose form (Fig. 2). The absolute configuration was determined from the starting material. The crystal exists as an hydrogen bonded network with each molecule acting as a donor and acceptor for 4 hydrogen bonds. Non-conventional hydrogen bonds have been ignored.

Experimental

The title compound was recrystallized from methanol: m.p. 120–123°C; [α]_D²⁰ -18.6 (c, 0.94 in H₂O).

Refinement

In the absence of significant anomalous scattering, Friedel pairs were merged and the absolute configuration was assigned from the starting material.

The H atoms were all located in a difference map, but those attached to carbon 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 U_iso(H) (in the range 1.2–1.5 times U_eq of the parent atom), after which the positions were refined with riding constraints.

Figures

Fig. 1.

Synthetic scheme.

Fig. 2.

The title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitary radius.

Fig. 3.

Packing diagram of the title compound projected along the a-axis.

Crystal data

C6H12O5	F000 = 352
Mr = 164.16	Dx = 1.511 Mg m−3
Orthorhombic, P212121	Mo Kα radiation λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 890 reflections
a = 6.4939 (3) Å	θ = 5–27º
b = 7.4874 (4) Å	µ = 0.13 mm−1
c = 14.8382 (8) Å	T = 150 K
V = 721.47 (6) Å3	Plate, colourless
Z = 4	0.25 × 0.25 × 0.02 mm

Data collection

Nonius KappaCCD diffractometer	863 reflections with I > 2.0σ(I)
Monochromator: graphite	Rint = 0.037
T = 150 K	θmax = 27.5º
ω scans	θmin = 5.2º
Absorption correction: multi-scanDENZO/SCALEPACK (Otwinowski & Minor, 1997)	h = −8→8
Tmin = 0.97, Tmax = 1.00	k = −9→9
4390 measured reflections	l = −19→19
968 independent reflections

Refinement

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.029	Method = Modified Sheldrick w = 1/[σ2(F2) + ( 0.04P)2 + 0.04P] ,where P = (max(Fo2,0) + 2Fc2)/3
wR(F2) = 0.072	(Δ/σ)max = 0.0002
S = 1.03	Δρmax = 0.24 e Å−3
968 reflections	Δρmin = −0.21 e Å−3
100 parameters	Extinction correction: None
Primary atom site location: structure-invariant direct methods

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.95002 (16)	0.08900 (18)	0.35376 (7)	0.0210
C2	0.7416 (2)	0.1250 (2)	0.32982 (10)	0.0175
C3	0.6113 (3)	0.1509 (3)	0.41551 (10)	0.0188
O4	0.65011 (17)	0.31964 (16)	0.45740 (7)	0.0183
C5	0.6150 (2)	0.4717 (2)	0.39897 (10)	0.0194
C6	0.6412 (3)	0.6382 (3)	0.45454 (12)	0.0271
C7	0.7657 (2)	0.4593 (2)	0.32003 (10)	0.0187
C8	0.7208 (2)	0.2889 (3)	0.26846 (10)	0.0186
O9	0.85143 (18)	0.26675 (18)	0.19178 (7)	0.0243
O10	0.97297 (17)	0.45445 (18)	0.35319 (8)	0.0232
O11	0.40458 (18)	0.1333 (2)	0.39115 (8)	0.0254
H21	0.6937	0.0193	0.2985	0.0197*
H31	0.6474	0.0567	0.4621	0.0197*
H51	0.4756	0.4675	0.3773	0.0236*
H61	0.6179	0.7441	0.4188	0.0406*
H62	0.5480	0.6346	0.5057	0.0398*
H63	0.7791	0.6452	0.4743	0.0401*
H71	0.7508	0.5628	0.2786	0.0214*
H81	0.5761	0.2938	0.2475	0.0221*
H7	0.8826	0.3664	0.1753	0.0374*
H8	0.9866	0.1914	0.3632	0.0333*
H10	1.0243	0.5538	0.3399	0.0350*
H1	0.3258	0.1436	0.4383	0.0408*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0198 (5)	0.0204 (7)	0.0229 (6)	0.0030 (5)	−0.0010 (5)	−0.0005 (5)
C2	0.0184 (7)	0.0188 (9)	0.0153 (7)	−0.0001 (8)	−0.0013 (6)	−0.0015 (6)
C3	0.0209 (8)	0.0186 (9)	0.0169 (7)	−0.0037 (7)	0.0005 (6)	−0.0021 (7)
O4	0.0223 (5)	0.0178 (7)	0.0150 (5)	−0.0008 (5)	−0.0006 (5)	0.0007 (5)
C5	0.0220 (8)	0.0184 (9)	0.0179 (7)	0.0019 (8)	−0.0015 (7)	0.0002 (7)
C6	0.0378 (10)	0.0202 (10)	0.0232 (8)	0.0022 (9)	0.0025 (9)	−0.0040 (7)
C7	0.0183 (7)	0.0202 (9)	0.0176 (7)	0.0031 (7)	0.0006 (7)	0.0029 (7)
C8	0.0197 (7)	0.0212 (10)	0.0149 (7)	0.0011 (7)	0.0013 (6)	−0.0005 (7)
O9	0.0335 (6)	0.0213 (7)	0.0180 (5)	0.0043 (6)	0.0087 (5)	0.0025 (5)
O10	0.0195 (5)	0.0195 (7)	0.0306 (6)	−0.0026 (5)	−0.0015 (5)	0.0023 (6)
O11	0.0199 (5)	0.0331 (8)	0.0233 (5)	−0.0074 (6)	0.0028 (5)	−0.0047 (6)

Geometric parameters (Å, °)

O1—C2	1.4250 (19)	C6—H61	0.966
O1—H8	0.815	C6—H62	0.971
C2—C3	1.540 (2)	C6—H63	0.944
C2—C8	1.534 (2)	C7—C8	1.516 (2)
C2—H21	0.969	C7—O10	1.4334 (19)
C3—O4	1.430 (2)	C7—H71	0.994
C3—O11	1.3965 (19)	C8—O9	1.4288 (18)
C3—H31	1.015	C8—H81	0.990
O4—C5	1.449 (2)	O9—H7	0.811
C5—C6	1.504 (2)	O10—H10	0.839
C5—C7	1.529 (2)	O11—H1	0.870
C5—H51	0.962
C2—O1—H8	98.1	C5—C6—H62	109.6
O1—C2—C3	109.88 (12)	H61—C6—H62	110.8
O1—C2—C8	112.50 (13)	C5—C6—H63	108.9
C3—C2—C8	109.93 (14)	H61—C6—H63	105.9
O1—C2—H21	105.7	H62—C6—H63	110.5
C3—C2—H21	108.8	C5—C7—C8	108.34 (14)
C8—C2—H21	109.9	C5—C7—O10	109.84 (12)
C2—C3—O4	111.93 (14)	C8—C7—O10	109.43 (14)
C2—C3—O11	107.62 (12)	C5—C7—H71	111.3
O4—C3—O11	111.43 (15)	C8—C7—H71	109.0
C2—C3—H31	110.4	O10—C7—H71	108.9
O4—C3—H31	106.1	C2—C8—C7	110.89 (12)
O11—C3—H31	109.4	C2—C8—O9	109.12 (13)
C3—O4—C5	113.97 (11)	C7—C8—O9	112.67 (13)
O4—C5—C6	107.79 (12)	C2—C8—H81	107.4
O4—C5—C7	108.05 (13)	C7—C8—H81	108.0
C6—C5—C7	113.45 (14)	O9—C8—H81	108.5
O4—C5—H51	108.8	C8—O9—H7	106.4
C6—C5—H51	108.5	C7—O10—H10	105.7
C7—C5—H51	110.1	C3—O11—H1	110.4
C5—C6—H61	111.2

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O9—H7···O1i	0.81	2.04	2.818 (2)	162
O1—H8···C7	0.82	2.55	3.061 (2)	122
O1—H8···O10	0.82	1.98	2.740 (2)	156
O10—H10···O9i	0.84	1.85	2.686 (2)	177
O11—H1···O4ii	0.87	1.94	2.812 (2)	177

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