organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

5-Amino-5-de­oxy-2-C-hy­droxy­methyl-2,3-O-iso­propyl­­idene-D-talono-1,5-lactam

aDepartment of Organic Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England, bChemical Crystallography Laboratory, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England, and cMolecular Nature Ltd, Insitute of Grassland and Environmental Research, Aberystwyth SY23 3EB, Wales
*Correspondence e-mail: andrew.cowley@chem.ox.ac.uk

(Received 3 September 2004; accepted 7 October 2004; online 30 October 2004)

The title compound, C10H17NO6, was prepared by carrying out three SN2 displacements on a branched sugar derivative, one of which was not planned. Its crystal structure was determined to confirm the identity and stereochemistry of the product.

Comment

Even though the value of carbohydrate building blocks to provide access to enantiomerically pure synthetic materials is well recognized, there are no easily available branched sugar intermediates (Bols, 1996[Bols, M. (1996). Carbohydrate Building Blocks. New York: John Wiley and Sons.]). The Kiliani reaction on cheap ketoses, although hitherto hardly explored, produces protected branched carbohydrates easily. Such materials are likely to have many uses, but initially we are studying the easy preparation of branched sugar mimetics in which the ring oxy­gen of the sugar is replaced by nitro­gen (Winchester & Fleet, 1992[Winchester, B. & Fleet, G. W. J. (1992). Glycobiology, 2, 199-210.]; Asano et al., 2000[Asano, N., Nash, R. J., Molyneux, R. J. & Fleet, G. W. J. (2000). Tetrahedron Asymmetry, 11, 1645-1680.]). The biological properties of branched alkaloids are promising (Ichikawa & Igarashi, 1995[Ichikawa, Y. & Igarashi, Y. (1995). Tetrahedron Lett. 36, 4586-4587.], Ichikawa et al., 1998[Ichikawa, Y., Igarashi, Y., Ichikawa, M. & Suhara, Y. (1998). J. Am. Chem. Soc. 120, 3007-3018.]), but the difficulties in the synthesis of such compounds have hindered a substantive investigation of these properties. The branched diacetonide (I) was readily prepared from D-fructose and was readily transformed into the tri­fluoro­methane­sulfonate (2[link]). It was anticipated that treatment of (2[link]) with an oxy­gen nucleophile would result in a single inversion of configuration at C5. However, the major product isolated, (3) had undergone inversion of configuration at both C4 and C5. The alcohol (3[link]) was elaborated by standard reactions to the title lactam (4), the structure of which is hereby firmly established by X-ray crystallographic analysis. The configuration at C4 of the lactam (4[link]) unequivocally demonstrates that an unexpected double inversion took place in the transformation of (2[link]) to (3[link]).[link]

[Scheme 1]

The NH and OH groups all form clearly defined intermolecular hydrogen bonds, linking bilayers of mol­ecules running parallel to the crystallographic ab plane.

[Figure 1]
Figure 1
View of the title mol­ecule, showing displacement ellipsoids at the 40% probability level. H atoms are shown as spheres of arbitrary radius.

Experimental

The lactam (4[link]) was prepared from the diacetonide (1[link]) derived from fructose (Hotchliss et al., 2004[Hotchkiss, D., Soengas, R., Simone, M. I., van Ameijde, J., Hunter, S., Cowley, A. R. & Fleet, G. W. J. (2004). Tetrahedron Lett. 45. Accepted.]). The title material was crystallized from methanol to yield colourless plates.

Crystal data
  • C10H17NO6

  • Mr = 247.25

  • Monoclinic, P21

  • a = 6.1266 (2) Å

  • b = 6.7254 (2) Å

  • c = 13.8419 (5) Å

  • β = 99.6456 (14)°

  • V = 562.28 (3) Å3

  • Z = 2

  • Dx = 1.460 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 5291 reflections

  • θ = 5–28°

  • μ = 0.12 mm−1

  • T = 150 K

  • Plate, colourless

  • 0.38 × 0.38 × 0.14 mm

Data collection
  • Nonius KappaCCD diffractometer

  • ω scans

  • Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr and R. M. Sweet, pp. 307-326. New York: Academic Press.]) Tmin = 0.96, Tmax = 0.98

  • 5291 measured reflections

  • 1372 independent reflections

  • 1211 reflections with I > 3σ(I)

  • Rint = 0.030

  • θmax = 27.4°

  • h = −7 → 7

  • k = −8 → 8

  • l = −17 → 17

Refinement
  • Refinement on F

  • R = 0.028

  • wR = 0.034

  • S = 1.10

  • 1211 reflections

  • 170 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Weighting scheme: see text

  • (Δ/σ)max = 0.003

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bonding geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O6i 0.94 (3) 1.96 (3) 2.8510 (19) 156 (3)
O2—H2⋯O1ii 0.86 (3) 1.89 (3) 2.7408 (17) 169 (3)
O5—H3⋯O2iii 0.91 (4) 1.86 (4) 2.7338 (18) 161 (3)
O6—H4⋯O5iv 0.93 (3) 1.75 (3) 2.6610 (18) 167 (3)
Symmetry codes: (i) [-x,y-{\script{1\over 2}},1-z]; (ii) 1+x,y,z; (iii) x,1+y,z; (iv) x-1,y,z.

The weighting scheme used a Chebychev polynomial (Watkin, 1994[Watkin, D. J. (1994). Acta Cryst. A50, 411-437.], Prince, 1982[Prince, E. (1982). Mathematical Techniques in Crystallography and Materials Science. New York: Springer-Verlag.]): w = {1 − [(Fo − Fc)/6σ(F)]2}2/[1.14T0(x) + 0.561T1(x) + 0.916T2(x)], where x = Fc/Fmax.

Friedel pairs of reflections were merged prior to use in refinement. The absolute configuration of the compound was assumed on the basis of that of the optically pure starting material. The NH and OH H atoms were located in a difference Fourier map and their coordinates and isotropic displacement parameters were subsequently refined. All other H atoms were positioned geometrically (C—H = 1.00 Å), with isotropic displacement parameters set equal to 1.2Ueq of the parent atom.

Data collection: COLLECT (Nonius, 2000[Nonius (2000). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr and R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: COLLECT and DENZO; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003[Betteridge, P. W., Carruthers, J. R., Cooper, R. I., Prout, K. & Watkin, D. J. (2003). J. Appl. Cryst. 36, 1487.]); molecular graphics: ATOMS (Shape Software, 2002[Shape Software (2002). ATOMS for Windows. Version 6.0. Shape Software, 521 Hidden Valley Road, Kingsport, TN 37663, USA.]); software used to prepare material for publication: CRYSTALS.

Supporting information


Comment top

Even though the value of carbohydrate building blocks to provide access to enantiomerically pure synthetic materials is well recognized, there are no easily available branched sugar intermediates (Bols, 1996). The Kiliani reaction on cheap ketoses, although hitherto hardly explored, produces protected branched carbohydrates easily. Such materials are likely to have many uses but initially we are studying the easy preparation of branched sugar mimetics in which the ring oxygen of the sugar is replaced by nitrogen (Winchester & Fleet, 1992; Asano et al., 2001). The biological properties of branched alkaloids are promising (Ichikawa & Igarashi, 1995, Ichikawa et al., 1998), but the difficulties in the synthesis of such compounds have hindered a substantive investigation of these properties. The branched diactonide (1) was readily prepared from D-fructose and was readily transformed into the trifluoromethanesulfonate (2). It was anticipated that treatment of (2) with an oxygen nucleophile would result in a single inversion of configuration at C5. However, the major product isolated 3 had undergone inversion of configuration at both C4 and C5. The alcohol (3) was elaborated by standard reactions to the title lactam (4), the structure of which is hereby firmly established by X-ray crystallographic analysis. The configuration at C4 of the lactam (4) unequivocally demonstrated that an unexpected double inversion had taken place in the transformation of (2) to (3).

The NH and OH groups all form clearly defined intermolecular hydrogen bonds, linking bilayers of molecules running parallel to the crystallographic ab plane.

Experimental top

The title material was crystallized from methanol to yield colourless plates.

Refinement top

Friedel pairs of reflections were merged prior to use in refinement. The absolute configuration of the crystal was assumed on the basis of that of the optically pure starting material. The NH and OH H atoms were located in a difference Fourier map and their coordinates and isotropic displacement parameters were subsequently refined. All other H atoms were positioned geometrically, with isotropic displacement parameters set equal to 1.2Ueq of the parent atom.

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: COLLECT and DENZO; data reduction: COLLECT and DENZO (Otwinowski & Minor, 1996); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: ATOMS (Shape Software, 2002); software used to prepare material for publication: CRYSTALS.

Figures top
[Figure 1] Fig. 1. View of the title molecule, showing displacement ellipsoids at the 40% probabality level. H atoms are shown as spheres of arbitrary radius.
5-Amino-5-deoxy-2-C-hydroxymethyl-2,3-O-isopropylidene-D-talono-1,5-lactam top
Crystal data top
C10H17NO6F(000) = 264
Mr = 247.25Dx = 1.460 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 6.1266 (2) ÅCell parameters from 5291 reflections
b = 6.7254 (2) Åθ = 5–28°
c = 13.8419 (5) ŵ = 0.12 mm1
β = 99.6456 (14)°T = 150 K
V = 562.28 (3) Å3Plate, colourless
Z = 20.38 × 0.38 × 0.14 mm
Data collection top
Nonius KappaCCD
diffractometer
1211 reflections with I > 3.00u(I)
Graphite monochromatorRint = 0.030
ω scansθmax = 27.4°, θmin = 5.1°
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1996)
h = 77
Tmin = 0.96, Tmax = 0.98k = 88
5291 measured reflectionsl = 1717
1372 independent reflections
Refinement top
Refinement on FPrimary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.028H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.034 Method, part 1, Chebychev polynomial, (Watkin, 1994, Prince, 1982) [weight] = 1.0/[A0*T0(x) + A1*T1(x) ··· + An-1]*Tn-1(x)]
where Ai are the Chebychev coefficients listed below and x = F /Fmax Method = Robust Weighting (Prince, 1982) W = [weight] * [1-(deltaF/6*sigmaF)2]2 Ai are: 1.14 0.561 0.916
S = 1.10(Δ/σ)max = 0.004
1211 reflectionsΔρmax = 0.20 e Å3
170 parametersΔρmin = 0.16 e Å3
1 restraint
Crystal data top
C10H17NO6V = 562.28 (3) Å3
Mr = 247.25Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.1266 (2) ŵ = 0.12 mm1
b = 6.7254 (2) ÅT = 150 K
c = 13.8419 (5) Å0.38 × 0.38 × 0.14 mm
β = 99.6456 (14)°
Data collection top
Nonius KappaCCD
diffractometer
1372 independent reflections
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1996)
1211 reflections with I > 3.00u(I)
Tmin = 0.96, Tmax = 0.98Rint = 0.030
5291 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0281 restraint
wR(F2) = 0.034H atoms treated by a mixture of independent and constrained refinement
S = 1.10Δρmax = 0.20 e Å3
1211 reflectionsΔρmin = 0.16 e Å3
170 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.1580 (2)0.3518 (2)0.37174 (11)0.0176
C10.1315 (2)0.2536 (3)0.28694 (12)0.0160
C20.3054 (3)0.2808 (2)0.21935 (13)0.0154
C30.4612 (2)0.4553 (3)0.24723 (10)0.0153
C40.5232 (2)0.4908 (2)0.35601 (11)0.0151
C50.3214 (2)0.5061 (3)0.40842 (11)0.0161
O10.0245 (2)0.1385 (2)0.26071 (10)0.0239
C60.4241 (3)0.0847 (3)0.20754 (13)0.0206
O20.5652 (2)0.0291 (2)0.29613 (10)0.0215
O30.1949 (2)0.3367 (2)0.12375 (9)0.0211
O40.3350 (2)0.6200 (2)0.20346 (9)0.0182
C70.1964 (3)0.5502 (3)0.11614 (12)0.0183
C80.2954 (3)0.6069 (3)0.02649 (14)0.0292
C90.0325 (3)0.6348 (3)0.11512 (15)0.0303
O50.66148 (19)0.66075 (19)0.37549 (9)0.0196
C100.2106 (3)0.7109 (3)0.40523 (12)0.0203
O60.0666 (2)0.7158 (2)0.47624 (9)0.0245
H10.050 (5)0.324 (5)0.411 (2)0.042 (8)*
H20.699 (6)0.064 (6)0.293 (2)0.054 (9)*
H30.604 (6)0.768 (6)0.340 (2)0.052 (9)*
H40.075 (5)0.680 (5)0.4463 (19)0.038 (7)*
H310.60600.43170.22490.0186*
H410.60820.37090.38350.0179*
H510.38180.48420.47930.0194*
H610.51530.09990.15450.0252*
H620.31110.02200.18910.0252*
H810.29760.75500.02030.0355*
H820.45010.55450.03360.0355*
H830.20390.54850.03340.0355*
H910.02700.78290.10980.0358*
H920.08580.59740.17710.0358*
H930.13610.58000.05780.0358*
H1010.32630.81630.42050.0247*
H1020.12320.73470.33850.0247*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0164 (7)0.0179 (7)0.0198 (6)0.0030 (5)0.0066 (5)0.0004 (6)
C10.0130 (7)0.0138 (7)0.0217 (8)0.0014 (6)0.0043 (5)0.0041 (6)
C20.0166 (7)0.0140 (7)0.0159 (8)0.0015 (6)0.0038 (6)0.0003 (6)
C30.0151 (6)0.0147 (7)0.0167 (7)0.0016 (6)0.0045 (5)0.0009 (6)
C40.0140 (7)0.0152 (8)0.0155 (7)0.0008 (5)0.0011 (5)0.0004 (6)
C50.0147 (7)0.0186 (7)0.0152 (7)0.0019 (6)0.0026 (5)0.0004 (6)
O10.0182 (6)0.0233 (6)0.0307 (6)0.0075 (5)0.0056 (4)0.0016 (6)
C60.0246 (8)0.0146 (8)0.0237 (9)0.0000 (6)0.0076 (6)0.0018 (6)
O20.0155 (6)0.0166 (6)0.0326 (7)0.0008 (5)0.0047 (5)0.0034 (5)
O30.0300 (7)0.0156 (6)0.0166 (6)0.0047 (5)0.0004 (5)0.0006 (5)
O40.0234 (6)0.0134 (5)0.0162 (6)0.0013 (4)0.0010 (4)0.0009 (4)
C70.0208 (8)0.0164 (8)0.0170 (8)0.0048 (6)0.0011 (6)0.0010 (6)
C80.0362 (10)0.0332 (11)0.0192 (8)0.0112 (9)0.0076 (7)0.0018 (7)
C90.0208 (9)0.0315 (10)0.0371 (10)0.0010 (8)0.0004 (7)0.0023 (9)
O50.0141 (5)0.0185 (6)0.0248 (6)0.0042 (5)0.0007 (4)0.0012 (5)
C100.0178 (7)0.0227 (8)0.0213 (8)0.0004 (6)0.0063 (6)0.0046 (7)
O60.0161 (5)0.0370 (7)0.0215 (6)0.0008 (5)0.0060 (4)0.0103 (6)
Geometric parameters (Å, º) top
N1—C11.333 (2)C6—H621.000
N1—C51.471 (2)O2—H20.86 (3)
N1—H10.94 (3)O3—C71.440 (2)
C1—C21.542 (2)O4—C71.435 (2)
C1—O11.236 (2)C7—C81.518 (2)
C2—C31.521 (2)C7—C91.511 (2)
C2—C61.528 (2)C8—H811.000
C2—O31.432 (2)C8—H821.000
C3—C41.509 (2)C8—H831.000
C3—O41.426 (2)C9—H911.000
C3—H311.000C9—H921.000
C4—C51.538 (2)C9—H931.000
C4—O51.4215 (19)O5—H30.91 (4)
C4—H411.000C10—O61.427 (2)
C5—C101.533 (2)C10—H1011.000
C5—H511.000C10—H1021.000
C6—O21.427 (2)O6—H40.93 (3)
C6—H611.000
C1—N1—C5128.95 (13)C2—C6—H62108.982
C1—N1—H1114.5 (19)O2—C6—H62108.982
C5—N1—H1116 (2)H61—C6—H62109.467
N1—C1—C2118.74 (14)C6—O2—H2109 (2)
N1—C1—O1122.89 (15)C2—O3—C7108.74 (13)
C2—C1—O1118.36 (15)C3—O4—C7107.81 (13)
C1—C2—C3113.93 (13)O3—C7—O4105.95 (14)
C1—C2—C6110.60 (13)O3—C7—C8108.57 (16)
C3—C2—C6113.79 (13)O4—C7—C8110.19 (14)
C1—C2—O3108.93 (13)O3—C7—C9111.03 (15)
C3—C2—O3102.22 (13)O4—C7—C9107.58 (15)
C6—C2—O3106.70 (13)C8—C7—C9113.27 (16)
C2—C3—C4114.70 (13)C7—C8—H81109.467
C2—C3—O4102.65 (12)C7—C8—H82109.467
C4—C3—O4109.21 (13)H81—C8—H82109.476
C2—C3—H31110.567C7—C8—H83109.467
C4—C3—H31104.177H81—C8—H83109.476
O4—C3—H31115.933H82—C8—H83109.476
C3—C4—C5113.15 (13)C7—C9—H91109.467
C3—C4—O5111.05 (13)C7—C9—H92109.467
C5—C4—O5110.94 (13)H91—C9—H92109.476
C3—C4—H41106.285C7—C9—H93109.467
C5—C4—H41106.403H91—C9—H93109.476
O5—C4—H41108.711H92—C9—H93109.476
N1—C5—C4110.13 (13)C4—O5—H3112 (2)
N1—C5—C10110.58 (13)C5—C10—O6108.81 (14)
C4—C5—C10115.68 (13)C5—C10—H101109.637
N1—C5—H51110.696O6—C10—H101109.637
C4—C5—H51104.970C5—C10—H102109.637
C10—C5—H51104.465O6—C10—H102109.637
C2—C6—O2111.42 (13)H101—C10—H102109.467
C2—C6—H61108.982C10—O6—H4109.0 (16)
O2—C6—H61108.982
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O6i0.94 (3)1.96 (3)2.8510 (19)156 (3)
O2—H2···O1ii0.86 (3)1.89 (3)2.7408 (17)169 (3)
O5—H3···O2iii0.91 (4)1.86 (4)2.7338 (18)161 (3)
O6—H4···O5iv0.93 (3)1.75 (3)2.6610 (18)167 (3)
Symmetry codes: (i) x, y1/2, z+1; (ii) x+1, y, z; (iii) x, y+1, z; (iv) x1, y, z.

Experimental details

Crystal data
Chemical formulaC10H17NO6
Mr247.25
Crystal system, space groupMonoclinic, P21
Temperature (K)150
a, b, c (Å)6.1266 (2), 6.7254 (2), 13.8419 (5)
β (°) 99.6456 (14)
V3)562.28 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.38 × 0.38 × 0.14
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1996)
Tmin, Tmax0.96, 0.98
No. of measured, independent and
observed [I > 3.00u(I)] reflections
5291, 1372, 1211
Rint0.030
(sin θ/λ)max1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.028, 0.034, 1.10
No. of reflections1211
No. of parameters170
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.16

Computer programs: COLLECT (Nonius, 2000), COLLECT and DENZO (Otwinowski & Minor, 1996), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), ATOMS (Shape Software, 2002), CRYSTALS.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O6i0.94 (3)1.96 (3)2.8510 (19)156 (3)
O2—H2···O1ii0.86 (3)1.89 (3)2.7408 (17)169 (3)
O5—H3···O2iii0.91 (4)1.86 (4)2.7338 (18)161 (3)
O6—H4···O5iv0.93 (3)1.75 (3)2.6610 (18)167 (3)
Symmetry codes: (i) x, y1/2, z+1; (ii) x+1, y, z; (iii) x, y+1, z; (iv) x1, y, z.
 

Acknowledgements

Financial support (to RS and MIS) provided through the European Community's Human Potential Programme under contract HPRN-CT-2002-00173 is gratefully acknowledged.

References

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