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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 64| Part 10| October 2008| Pages o1902-o1903

3-O-Benzhydryl-2,5-dide­­oxy-2,5-imino-2-C-methyl-L-lyxono-1,4-lactone

aDepartment of Organic Chemistry, Chemical Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England, and bDepartment of Chemical Crystallography, Chemical Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England
*Correspondence e-mail: victoria.booth@chem.ox.ac.uk

(Received 16 July 2008; accepted 31 August 2008; online 6 September 2008)

The title bicyclic lactone, C19H19NO3, is an inter­mediate in the synthesis of chiral α-methyl­prolines and branched C-methyl pyrrolidines; the absolute configuration was determined by the use of D-erythronolactone as the starting material. It exhibits no unusual crystal packing features, and each mol­ecule acts as a donor and acceptor for one C—H⋯O hydrogen bond.

Related literature

For use of carbohydrates in synthesis see: Monneret & Florent (1994[Monneret, C. & Florent, J. C. (1994). Synlett, pp. 305-318.]); Ireland et al. (1983[Ireland, R. E., Courtney, L. & Fitzsimmons, B. J. (1983). J. Org. Chem. 48, 5186-5198.]); Hotchkiss et al. (2006[Hotchkiss, D. J., Jenkinson, S. F., Storer, R., Heinz, T. & Fleet, G. W. J. (2006). Tetrahedron Lett. 47, 315-318.], 2007a[Hotchkiss, D. J., Soengas, R., Booth, K. V., Weymouth-Wilson, A. C., Eastwick-Field, V. & Fleet, G. W. J. (2007a). Tetrahedron Lett. 48, 517-520.],b[Hotchkiss, D. J., Kato, A., Odell, B., Claridge, T. D. W. & Fleet, G. W. J. (2007b). Tetrahedron Asymmetry, 18, 500-512.]); Dukhan et al. (2005[Dukhan, D., Bosc, E., Peyronnet, J., Storer, R. & Gosselin, G. (2005). Nucleosides, Nucleotides Nucleic Acids, 24, 577-580.]); Rao et al. (2008[Rao, D., Yoshihara, A., Gullapalli, P., Morimoto, K., Takata, G., da Cruz, F. P., Jenkinson, S. F., Wormald, M. R., Dwek, R. A., Fleet, G. W. J. & Izumori, K. (2008). Tetrahedron Lett. 49, 3316-3321.]); Punzo et al. (2005a[Punzo, F., Watkin, D. J., Jenkinson, S. F. & Fleet, G. W. J. (2005a). Acta Cryst. E61, o127-o129.],b[Punzo, F., Watkin, D. J., Jenkinson, S. F., Cruz, F. P. & Fleet, G. W. J. (2005b). Acta Cryst. E61, o511-o512.]); Da Cruz et al. (2008[Da Cruz, F. P., Horne, G. & Fleet, G. W. J. (2008). In preparation.]). For related crystallographic literature see: Larson (1970[Larson, A. C. (1970). Crystallographic Computing, edited by F. R. Ahmed, S. R. Hall & C. P. Huber, pp. 291-294. Copenhagen: Munksgaard.]); Prince (1982[Prince, E. (1982). Mathematical Techniques in Crystallography and Materials Science. Springer-Verlag, New York.]); Watkin (1994[Watkin, D. (1994). Acta Cryst. A50, 411-437.]).

[Scheme 1]

Experimental

Crystal data
  • C19H19NO3

  • Mr = 309.36

  • Orthorhombic, P 21 21 21

  • a = 9.0336 (2) Å

  • b = 10.0498 (2) Å

  • c = 17.5941 (4) Å

  • V = 1597.30 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 150 K

  • 0.30 × 0.25 × 0.25 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • 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 & R. M. Sweet, pp. 307-326. New York: Academic Press.]) Tmin = 0.94, Tmax = 0.98

  • 25603 measured reflections

  • 2071 independent reflections

  • 1411 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.101

  • S = 0.86

  • 2071 reflections

  • 212 parameters

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

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C20—H201⋯O10i 0.93 2.36 3.293 (3) 174
Symmetry code: (i) [-x+{\script{3\over 2}}, -y+1, z+{\script{1\over 2}}].

Data collection: COLLECT (Nonius, 1997-2001[Nonius (1997-2001). COLLECT. Nonius BV, Delft, The Netherlands.]).; cell refinement: 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 & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO/SCALEPACK; 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: CAMERON (Watkin et al., 1996[Watkin, D. J., Prout, C. K. & Pearce, L. J. (1996). CAMERON. Chemical Crystallography Laboratory, Oxford, UK.]); software used to prepare material for publication: CRYSTALS.

Supporting information


Comment top

Carbon-branched sugar lactones have hitherto been rarely used for the synthesis of enantiopure chiral targets (Monneret & Florent, 1994; Ireland et al., 1983). 2-C-Methyl-D-ribonolactone has become readily available in large amounts (Hotchkiss et al., 2007a) and has been used in the synthesis of branched α-C-nucleosides (Dukhan et al., 2005), 4-C-methylpentuloses (Rao et al., 2008) and branched imino sugars (Hotchkiss et al., 2007b). Derivatives of 2-C-methyl-D-arabinonolactone, such as 2, are accessible from D-erythronolactone 1 by addition of methyl magnesium bromide followed by further reaction with sodium cyanide (Hotchkiss et al., 2006; Punzo et al., 2005a). The tertiary alcohol 2 may be efficiently converted into the ribo-azide 3, the structure of which has been confirmed by X-ray crystallographic analysis (Da Cruz et al., 2008; Punzo et al., 2005b). The relative stereochemistry of 4 is firmly established in this paper by X-ray crystallographic analysis and the absolute configuration is defined by the use of D-erythronolactone 1 as the starting material.

The title compound exhibits no unusual crystal packing features. Each molecule acts as a donor and acceptor for one hydrogen bond, forming chains approximately parallel to the a-axis. A suggested hydrogen bond [N7 - H1 - O10] has been ignored in the packing diagram as it exceeds the limits of standard hydrogen bond length (2.52 Å)

Related literature top

For related literature, see: Monneret & Florent (1994); Ireland et al. (1983); Hotchkiss et al. (2006, 2007a,b); Dukhan et al. (2005); Rao et al. (2008); Punzo et al. (2005a,b); Da Cruz et al. (2008); Larson (1970); Prince (1982); Watkin (1994).

Experimental top

The title compound was recrystallized from cyclohexane and diethyl ether: m.p. 116–118°C; [α]D21 -26.0 (c, 1.0 in MeCN).

Refinement top

In the absence of significant anomalous scattering, Friedel pairs were merged. 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, N—H in the range 0.86–0.89 N—H to 0.86 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.

Computing details top

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

Figures top
[Figure 1] Fig. 1. Synthetic scheme.
[Figure 2] Fig. 2. The title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitary radius.
[Figure 3] Fig. 3. Packing diagram showing hydrogen bonded chains running parallel to the a-axis.
(I) top
Crystal data top
C19H19NO3F(000) = 656
Mr = 309.36Dx = 1.286 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6711 reflections
a = 9.0336 (2) Åθ = 5–27°
b = 10.0498 (2) ŵ = 0.09 mm1
c = 17.5941 (4) ÅT = 150 K
V = 1597.30 (6) Å3Block, colourless
Z = 40.30 × 0.25 × 0.25 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
1411 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
ω scansθmax = 27.5°, θmin = 5.2°
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
h = 1111
Tmin = 0.94, Tmax = 0.98k = 1312
25603 measured reflectionsl = 2222
2071 independent reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.029 Method, part 1, Chebychev polynomial, (Watkin, 1994) [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: 16.5 25.4 13.4 3.97
wR(F2) = 0.101(Δ/σ)max = 0.000186
S = 0.86Δρmax = 0.21 e Å3
2071 reflectionsΔρmin = 0.21 e Å3
212 parametersExtinction correction: Larson (1970), Equation 22
0 restraintsExtinction coefficient: 420 (70)
Primary atom site location: structure-invariant direct methods
Crystal data top
C19H19NO3V = 1597.30 (6) Å3
Mr = 309.36Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.0336 (2) ŵ = 0.09 mm1
b = 10.0498 (2) ÅT = 150 K
c = 17.5941 (4) Å0.30 × 0.25 × 0.25 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
2071 independent reflections
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
1411 reflections with I > 2σ(I)
Tmin = 0.94, Tmax = 0.98Rint = 0.053
25603 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.101H atoms treated by a mixture of independent and constrained refinement
S = 0.86Δρmax = 0.21 e Å3
2071 reflectionsΔρmin = 0.21 e Å3
212 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.68597 (16)0.81026 (14)0.31734 (9)0.0272
C20.6994 (2)0.69016 (19)0.27608 (12)0.0242
C30.7190 (3)0.5647 (2)0.32511 (13)0.0286
O40.76321 (17)0.46691 (14)0.26720 (9)0.0310
C50.8514 (3)0.5332 (2)0.21745 (12)0.0301
C60.8569 (2)0.6776 (2)0.24385 (12)0.0281
N70.9525 (2)0.6653 (2)0.31282 (12)0.0325
C80.8577 (3)0.5979 (2)0.37011 (13)0.0337
C90.9106 (3)0.7768 (3)0.18667 (15)0.0392
O100.9132 (2)0.47855 (18)0.16574 (10)0.0420
C110.5358 (2)0.8483 (2)0.33392 (12)0.0251
C120.5418 (2)0.9877 (2)0.36769 (12)0.0266
C130.6550 (3)1.0751 (2)0.34846 (13)0.0315
C140.6565 (3)1.2033 (2)0.37762 (14)0.0370
C150.5459 (3)1.2459 (2)0.42665 (15)0.0406
C160.4328 (3)1.1595 (2)0.44577 (15)0.0402
C170.4305 (3)1.0309 (2)0.41629 (13)0.0344
C180.4604 (2)0.74727 (19)0.38447 (11)0.0253
C190.5194 (3)0.7164 (2)0.45543 (12)0.0322
C200.4554 (3)0.6179 (3)0.50012 (13)0.0405
C210.3303 (3)0.5504 (2)0.47385 (16)0.0422
C220.2698 (3)0.5832 (2)0.40451 (16)0.0397
C230.3342 (3)0.6812 (2)0.35977 (13)0.0312
H210.62170.67910.23670.0282*
H310.63440.53650.35480.0341*
H810.83350.65810.41260.0399*
H820.90620.51760.38800.0400*
H911.01250.76350.17450.0585*
H920.90020.86650.20830.0596*
H930.85090.77210.14110.0587*
H1110.48140.85230.28510.0297*
H1310.73061.04740.31580.0374*
H1410.73371.26280.36360.0445*
H1510.54851.33150.44720.0487*
H1610.35641.18730.47880.0478*
H1710.35270.97330.42990.0420*
H1910.60400.76420.47310.0384*
H2010.49690.59680.54710.0498*
H2110.28660.48320.50360.0514*
H2210.18480.53710.38610.0482*
H2310.29130.70170.31180.0394*
H10.980 (4)0.748 (3)0.3251 (17)0.0433*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0237 (7)0.0228 (7)0.0350 (7)0.0012 (6)0.0009 (6)0.0054 (6)
C20.0247 (9)0.0202 (9)0.0278 (9)0.0005 (8)0.0007 (8)0.0031 (8)
C30.0329 (11)0.0225 (9)0.0303 (10)0.0008 (8)0.0044 (9)0.0034 (8)
O40.0330 (8)0.0242 (7)0.0359 (8)0.0010 (6)0.0024 (7)0.0046 (7)
C50.0280 (10)0.0300 (10)0.0324 (10)0.0045 (9)0.0011 (9)0.0022 (9)
C60.0243 (10)0.0261 (9)0.0340 (10)0.0013 (8)0.0015 (8)0.0012 (9)
N70.0264 (9)0.0306 (9)0.0404 (10)0.0011 (8)0.0073 (8)0.0026 (8)
C80.0375 (12)0.0306 (11)0.0331 (11)0.0063 (10)0.0040 (10)0.0005 (9)
C90.0358 (12)0.0361 (12)0.0457 (13)0.0005 (10)0.0122 (11)0.0078 (11)
O100.0462 (10)0.0399 (9)0.0398 (9)0.0087 (8)0.0086 (8)0.0084 (8)
C110.0224 (9)0.0270 (9)0.0260 (9)0.0031 (8)0.0017 (8)0.0001 (8)
C120.0285 (10)0.0247 (9)0.0265 (9)0.0045 (8)0.0011 (8)0.0008 (8)
C130.0307 (11)0.0267 (10)0.0372 (11)0.0034 (9)0.0025 (10)0.0025 (9)
C140.0385 (12)0.0246 (10)0.0478 (13)0.0016 (10)0.0034 (11)0.0045 (10)
C150.0496 (15)0.0239 (11)0.0482 (14)0.0065 (10)0.0007 (12)0.0049 (9)
C160.0421 (14)0.0335 (12)0.0452 (13)0.0062 (11)0.0100 (11)0.0051 (10)
C170.0361 (12)0.0289 (11)0.0383 (12)0.0023 (10)0.0079 (10)0.0004 (9)
C180.0265 (10)0.0230 (9)0.0265 (10)0.0029 (8)0.0018 (9)0.0030 (8)
C190.0408 (13)0.0287 (10)0.0272 (10)0.0053 (11)0.0017 (10)0.0039 (8)
C200.0570 (16)0.0362 (12)0.0283 (10)0.0138 (11)0.0069 (12)0.0020 (10)
C210.0474 (14)0.0292 (11)0.0501 (14)0.0055 (11)0.0209 (13)0.0051 (10)
C220.0348 (12)0.0299 (11)0.0544 (15)0.0019 (10)0.0093 (12)0.0035 (11)
C230.0284 (10)0.0295 (10)0.0356 (10)0.0009 (8)0.0004 (9)0.0038 (9)
Geometric parameters (Å, º) top
O1—C21.414 (2)C12—C131.390 (3)
O1—C111.439 (2)C12—C171.389 (3)
C2—C31.538 (3)C13—C141.387 (3)
C2—C61.537 (3)C13—H1310.935
C2—H210.992C14—C151.388 (4)
C3—O41.471 (2)C14—H1410.951
C3—C81.519 (3)C15—C161.382 (4)
C3—H310.968C15—H1510.934
O4—C51.358 (3)C16—C171.393 (3)
C5—C61.524 (3)C16—H1610.945
C5—O101.200 (3)C17—H1710.941
C6—N71.495 (3)C18—C191.393 (3)
C6—C91.497 (3)C18—C231.389 (3)
N7—C81.486 (3)C19—C201.390 (4)
N7—H10.89 (3)C19—H1910.954
C8—H810.986C20—C211.397 (4)
C8—H820.971C20—H2010.932
C9—H910.955C21—C221.377 (4)
C9—H920.983C21—H2110.942
C9—H930.968C22—C231.389 (4)
C11—C121.523 (3)C22—H2210.954
C11—C181.512 (3)C23—H2310.952
C11—H1110.990
C2—O1—C11114.34 (15)C12—C11—C18113.84 (17)
O1—C2—C3114.94 (16)O1—C11—H111107.6
O1—C2—C6109.83 (16)C12—C11—H111108.5
C3—C2—C691.88 (16)C18—C11—H111108.3
O1—C2—H21113.2C11—C12—C13120.81 (19)
C3—C2—H21112.4C11—C12—C17120.2 (2)
C6—C2—H21112.8C13—C12—C17119.0 (2)
C2—C3—O4100.99 (16)C12—C13—C14120.3 (2)
C2—C3—C8101.98 (17)C12—C13—H131119.9
O4—C3—C8106.51 (17)C14—C13—H131119.8
C2—C3—H31116.9C13—C14—C15120.6 (2)
O4—C3—H31113.0C13—C14—H141119.7
C8—C3—H31115.7C15—C14—H141119.7
C3—O4—C5106.11 (16)C14—C15—C16119.4 (2)
O4—C5—C6106.84 (17)C14—C15—H151120.5
O4—C5—O10122.5 (2)C16—C15—H151120.2
C6—C5—O10130.6 (2)C15—C16—C17120.2 (2)
C2—C6—C599.24 (16)C15—C16—H161120.3
C2—C6—N7104.02 (17)C17—C16—H161119.5
C5—C6—N7100.82 (17)C16—C17—C12120.6 (2)
C2—C6—C9119.55 (18)C16—C17—H171119.2
C5—C6—C9116.07 (19)C12—C17—H171120.3
N7—C6—C9114.42 (19)C11—C18—C19120.3 (2)
C6—N7—C8104.77 (16)C11—C18—C23120.47 (19)
C6—N7—H1106 (2)C19—C18—C23119.2 (2)
C8—N7—H1115 (2)C18—C19—C20120.4 (2)
C3—C8—N7102.82 (18)C18—C19—H191119.1
C3—C8—H81110.3C20—C19—H191120.5
N7—C8—H81111.3C19—C20—C21119.7 (2)
C3—C8—H82111.0C19—C20—H201119.8
N7—C8—H82109.7C21—C20—H201120.5
H81—C8—H82111.3C20—C21—C22119.9 (2)
C6—C9—H91111.7C20—C21—H211120.3
C6—C9—H92108.6C22—C21—H211119.9
H91—C9—H92107.9C21—C22—C23120.4 (3)
C6—C9—H93110.2C21—C22—H221120.3
H91—C9—H93110.1C23—C22—H221119.3
H92—C9—H93108.2C18—C23—C22120.4 (2)
O1—C11—C12106.90 (17)C18—C23—H231120.5
O1—C11—C18111.45 (16)C22—C23—H231119.1
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C20—H201···O10i0.932.363.293 (3)174
N7—H1···O10ii0.89 (2)2.52 (3)3.395 (3)168
Symmetry codes: (i) x+3/2, y+1, z+1/2; (ii) x+2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC19H19NO3
Mr309.36
Crystal system, space groupOrthorhombic, P212121
Temperature (K)150
a, b, c (Å)9.0336 (2), 10.0498 (2), 17.5941 (4)
V3)1597.30 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.30 × 0.25 × 0.25
Data collection
DiffractometerNonius KappaCCD area-detector
diffractometer
Absorption correctionMulti-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
Tmin, Tmax0.94, 0.98
No. of measured, independent and
observed [I > 2σ(I)] reflections
25603, 2071, 1411
Rint0.053
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.101, 0.86
No. of reflections2071
No. of parameters212
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.21, 0.21

Computer programs: COLLECT (Nonius, 1997-2001)., DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), CAMERON (Watkin et al., 1996).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C20—H201···O10i0.932.363.293 (3)174
Symmetry code: (i) x+3/2, y+1, z+1/2.
 

Acknowledgements

Financial support (to FPC) provided by the Fundacao para a Ciencia e Tecnologia of Portugal is gratefully acknowledged. We also thank the Oxford University Crystallography Service for use of the instruments.

References

First citationAltomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.  CrossRef Web of Science IUCr Journals Google Scholar
First citationBetteridge, P. W., Carruthers, J. R., Cooper, R. I., Prout, K. & Watkin, D. J. (2003). J. Appl. Cryst. 36, 1487.  Web of Science CrossRef IUCr Journals Google Scholar
First citationDa Cruz, F. P., Horne, G. & Fleet, G. W. J. (2008). In preparation.  Google Scholar
First citationDukhan, D., Bosc, E., Peyronnet, J., Storer, R. & Gosselin, G. (2005). Nucleosides, Nucleotides Nucleic Acids, 24, 577–580.  Google Scholar
First citationHotchkiss, D. J., Jenkinson, S. F., Storer, R., Heinz, T. & Fleet, G. W. J. (2006). Tetrahedron Lett. 47, 315–318.  Web of Science CrossRef CAS Google Scholar
First citationHotchkiss, D. J., Kato, A., Odell, B., Claridge, T. D. W. & Fleet, G. W. J. (2007b). Tetrahedron Asymmetry, 18, 500–512.  Web of Science CrossRef CAS Google Scholar
First citationHotchkiss, D. J., Soengas, R., Booth, K. V., Weymouth-Wilson, A. C., Eastwick-Field, V. & Fleet, G. W. J. (2007a). Tetrahedron Lett. 48, 517–520.  Web of Science CrossRef CAS Google Scholar
First citationIreland, R. E., Courtney, L. & Fitzsimmons, B. J. (1983). J. Org. Chem. 48, 5186–5198.  CrossRef CAS Web of Science Google Scholar
First citationLarson, A. C. (1970). Crystallographic Computing, edited by F. R. Ahmed, S. R. Hall & C. P. Huber, pp. 291–294. Copenhagen: Munksgaard.  Google Scholar
First citationMonneret, C. & Florent, J. C. (1994). Synlett, pp. 305–318.  CrossRef Google Scholar
First citationNonius (1997–2001). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
First citationPrince, E. (1982). Mathematical Techniques in Crystallography and Materials Science. Springer-Verlag, New York.  Google Scholar
First citationPunzo, F., Watkin, D. J., Jenkinson, S. F., Cruz, F. P. & Fleet, G. W. J. (2005b). Acta Cryst. E61, o511–o512.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationPunzo, F., Watkin, D. J., Jenkinson, S. F. & Fleet, G. W. J. (2005a). Acta Cryst. E61, o127–o129.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationRao, D., Yoshihara, A., Gullapalli, P., Morimoto, K., Takata, G., da Cruz, F. P., Jenkinson, S. F., Wormald, M. R., Dwek, R. A., Fleet, G. W. J. & Izumori, K. (2008). Tetrahedron Lett. 49, 3316–3321.  Web of Science CrossRef CAS Google Scholar
First citationWatkin, D. (1994). Acta Cryst. A50, 411–437.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationWatkin, D. J., Prout, C. K. & Pearce, L. J. (1996). CAMERON. Chemical Crystallography Laboratory, Oxford, UK.  Google Scholar

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Volume 64| Part 10| October 2008| Pages o1902-o1903
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