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Acta Cryst. (2009). E65, o679    [ doi:10.1107/S1600536809007260 ]

1-[4-(2,3,4,6-Tetra-O-acetyl-[beta]-D-allopyranosyloxy)benzylidene]thiosemicarbazide

L. Fu, X. Yin, L. Zheng, Y. Li and S. Yin

Abstract top

The title compound, C22H27N3O10S, was synthesized by reaction of an ethanol solution of helicid (systematic name: 4-formylphenl-[beta]-D-allopyranoside), thiosemicarbazide and acetic acid. The molecule exhibits a trans conformation with respect to the C=N double bond. The pyran ring adopts a chair conformation. In the crystal structure, the molecules are linked into chains parallel to the b axis by intermolecular N-H...O hydrogen bonds.

Comment top

The natural compound helicid (systematic name: 4-formylphenl-β-D-allopyranoside), which is extracted from the fruit of Helicia nilagirica Beed. (Chen et al., 1981), has been one major active ingredient of herb medicine used in China for a long time. It has manifested good biological effects on the central nervous system and low toxicity (Sha & Mao, 1987). Some derivatives of this compound have been reported to possess good pharmacological activity (Zhu et al., 2006; Yang et al., 2008). We report here the crystal structure of the title compound, whose synthesis has been already reported elsewhere (Wen et al., 2007).

In the molecule of the title compound (Fig. 1), the pyran ring adopts a chair conformation, with the hydroxy group at C3 in axial position and the other substituents at C1, C2 and C4 in equatorial positions. The average C–C bond length within the pyran ring is 1.524 (3) Å. The molecule exhibits a trans conformation with respect to the N1═C21 double bond, as indicated by the value of the C21–N1–N2–C22 torsion angle of -171.8 (6)°. In the crystal packing, intermolecular N—H···O hydrogen bonds (Table 1) link the molecules into chains running parallel to the b axis.

Related literature top

For the synthesis and biological activities of helicid, see: Chen et al. (1981); Sha & Mao (1987); Zhu et al. (2006); Yang et al. (2008); Wen et al. (2007).

Experimental top

A mixture of helicid (0.45 g, 1 mmol), acetic acid (0.5 ml) and thiosemicarbazide (0.09 g, 1 mmol) in ethanol (15 ml) was refluxed for 3 h. After cooling to room temperature, the precipitate was filtered, washed with ether and recrystallized from 95% alcohol to give a white powder. Colourless crystals suitable for X-ray analysis were obtained by slow evaporation of an ethanol/dichloromethane (4:1 v/v) solution at room temperature.

Refinement top

The H atom bound to N2 was located in a difference Fourier map and refined freely. All other H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.97 Å, N—H = 0.86 Å, and Uiso(H) = 1.2Ueq (C, N) or 1.5Ueq (C) for methyl H atoms.

Computing details top

Data collection: DIFRAC (Gabe et al., 1993); cell refinement: DIFRAC (Gabe et al., 1993); data reduction: NRCVAX (Gabe et al., 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.
1-[4-(2,3,4,6-Tetra-O-acetyl-β-D- allopyranosyloxy)benzylidene]thiosemicarbazide top
Crystal data top
C22H27N3O10SF(000) = 1104
Mr = 525.53Dx = 1.324 Mg m−3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 19 reflections
a = 9.848 (3) Åθ = 4.5–7.5°
b = 11.515 (3) ŵ = 0.18 mm−1
c = 23.250 (4) ÅT = 292 K
V = 2636.5 (12) Å3Block, colourless
Z = 40.54 × 0.46 × 0.24 mm
Data collection top
Enraf-Nonius CAD-4
diffractometer		2851 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.008
graphiteθmax = 26.0°, θmin = 1.8°
ω/2–θ scansh = −10→12
Absorption correction: ψ scan
(North et al., 1968)		k = −14→14
Tmin = 0.909, Tmax = 0.958l = −28→28
5423 measured reflections3 standard reflections every 200 reflections
4940 independent reflections intensity decay: 1.0%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.062H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.195 w = 1/[σ2(Fo2) + (0.1108P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max = 0.001
4940 reflectionsΔρmax = 0.30 e Å−3
329 parametersΔρmin = −0.27 e Å−3
0 restraintsAbsolute structure: Flack, (1983), 2108 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.35 (19)
Crystal data top
C22H27N3O10SV = 2636.5 (12) Å3
Mr = 525.53Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.848 (3) ŵ = 0.18 mm−1
b = 11.515 (3) ÅT = 292 K
c = 23.250 (4) Å0.54 × 0.46 × 0.24 mm
Data collection top
Enraf-Nonius CAD-4
diffractometer		2851 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.008
Tmin = 0.909, Tmax = 0.958θmax = 26.0°
5423 measured reflections3 standard reflections every 200 reflections
4940 independent reflections intensity decay: 1.0%
Refinement top
R[F2 > 2σ(F2)] = 0.062H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.195Δρmax = 0.30 e Å−3
S = 1.07Δρmin = −0.27 e Å−3
4940 reflectionsAbsolute structure: Flack, (1983), 2108 Friedel pairs
329 parametersFlack parameter: 0.35 (19)
0 restraints
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 > σ(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
xyzUiso*/Ueq
S10.67386 (19)0.79792 (13)1.07682 (8)0.0785 (5)
O10.0580 (3)0.0411 (3)0.84568 (15)0.0535 (9)
O2−0.0599 (4)−0.0865 (4)0.7938 (2)0.0862 (14)
O30.2305 (3)−0.1128 (3)0.71708 (14)0.0522 (9)
O40.1797 (6)−0.3014 (4)0.7185 (2)0.1061 (18)
O50.5080 (3)−0.0914 (3)0.74617 (14)0.0482 (8)
O60.6199 (5)−0.2413 (4)0.70896 (19)0.0865 (14)
O70.6077 (3)−0.1962 (3)0.84617 (15)0.0501 (8)
O80.5379 (4)−0.3793 (3)0.8569 (2)0.0781 (13)
O90.4971 (3)−0.0280 (3)0.92000 (13)0.0443 (7)
O100.3267 (3)0.0069 (3)0.85614 (12)0.0407 (7)
N10.6208 (4)0.4935 (4)1.00575 (18)0.0548 (11)
N20.6680 (5)0.5844 (4)1.0393 (2)0.0565 (12)
H2N10.708 (5)0.569 (5)1.066 (2)0.049 (17)*
N30.5385 (6)0.7104 (5)0.9885 (2)0.0832 (17)
H3A0.51340.65350.96700.100*
H3B0.50780.77910.98200.100*
C10.2764 (4)0.0066 (4)0.7979 (2)0.0402 (10)
H10.34060.05120.77450.048*
C20.2779 (4)−0.1174 (4)0.7760 (2)0.0433 (11)
H20.2159−0.16490.79900.052*
C30.4199 (5)−0.1666 (4)0.7796 (2)0.0459 (12)
H30.4230−0.24670.76540.055*
C40.4693 (4)−0.1589 (4)0.8422 (2)0.0396 (10)
H40.4119−0.20720.86690.048*
C50.4627 (4)−0.0333 (4)0.86160 (19)0.0367 (10)
H50.52450.01490.83870.044*
C60.1424 (4)0.0717 (5)0.7977 (2)0.0496 (13)
H6A0.16020.15460.79870.060*
H6B0.09430.05480.76230.060*
C7−0.0460 (5)−0.0308 (5)0.8376 (3)0.0597 (14)
C8−0.1389 (6)−0.0288 (6)0.8892 (3)0.0787 (19)
H8A−0.1704−0.10610.89710.118*
H8B−0.21520.02060.88140.118*
H8C−0.09030.00030.92200.118*
C90.1755 (6)−0.2085 (6)0.6944 (3)0.0694 (16)
C100.1184 (7)−0.1847 (6)0.6369 (3)0.083 (2)
H10A0.0842−0.25550.62060.125*
H10B0.1880−0.15350.61250.125*
H10C0.0457−0.12950.64030.125*
C110.6074 (5)−0.1380 (5)0.7148 (2)0.0541 (14)
C120.6992 (6)−0.0490 (6)0.6898 (3)0.0775 (19)
H12A0.7702−0.08670.66860.116*
H12B0.7382−0.00340.72020.116*
H12C0.64840.00060.66450.116*
C130.6297 (6)−0.3110 (5)0.8532 (2)0.0576 (14)
C140.7786 (6)−0.3377 (6)0.8568 (3)0.084 (2)
H14A0.8104−0.32270.89510.126*
H14B0.8272−0.28960.83010.126*
H14C0.7934−0.41790.84750.126*
C150.5342 (4)0.0805 (4)0.9425 (2)0.0401 (10)
C160.6049 (5)0.0769 (4)0.9935 (2)0.0512 (12)
H160.62490.00621.01090.061*
C170.6458 (5)0.1805 (5)1.0185 (2)0.0565 (14)
H170.69460.17881.05270.068*
C180.6155 (5)0.2860 (4)0.9935 (2)0.0439 (11)
C190.5441 (5)0.2877 (4)0.9419 (2)0.0516 (13)
H190.52350.35830.92450.062*
C200.5032 (5)0.1840 (4)0.9160 (2)0.0483 (12)
H200.45580.18480.88140.058*
C210.6587 (5)0.3937 (4)1.0228 (2)0.0500 (12)
H210.71550.38841.05460.060*
C220.6230 (6)0.6925 (5)1.0308 (2)0.0585 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.1123 (13)0.0390 (8)0.0844 (11)0.0062 (8)−0.0385 (10)−0.0059 (8)
O10.0362 (16)0.058 (2)0.067 (2)−0.0041 (15)0.0009 (15)−0.0004 (19)
O20.077 (3)0.083 (3)0.098 (4)−0.023 (2)−0.002 (2)−0.018 (3)
O30.062 (2)0.044 (2)0.050 (2)−0.0105 (17)−0.0127 (16)−0.0017 (16)
O40.170 (5)0.046 (3)0.103 (4)−0.036 (3)−0.061 (3)0.005 (3)
O50.0532 (18)0.0387 (18)0.0527 (19)0.0070 (16)0.0063 (15)−0.0047 (15)
O60.096 (3)0.075 (3)0.088 (3)0.035 (3)0.004 (3)−0.031 (3)
O70.0487 (17)0.0349 (18)0.067 (2)0.0089 (15)−0.0076 (17)−0.0047 (16)
O80.082 (3)0.031 (2)0.122 (4)−0.003 (2)−0.022 (2)−0.005 (2)
O90.0551 (17)0.0317 (16)0.0461 (18)−0.0059 (15)−0.0085 (15)−0.0055 (15)
O100.0422 (15)0.0364 (17)0.0435 (18)0.0015 (14)−0.0017 (14)−0.0034 (14)
N10.062 (3)0.049 (3)0.053 (3)−0.002 (2)−0.016 (2)−0.009 (2)
N20.077 (3)0.035 (2)0.058 (3)0.003 (2)−0.029 (3)0.000 (2)
N30.120 (5)0.046 (3)0.084 (4)0.004 (3)−0.046 (3)0.003 (3)
C10.045 (2)0.024 (2)0.051 (3)−0.0048 (19)0.000 (2)0.000 (2)
C20.050 (3)0.030 (2)0.050 (3)−0.003 (2)−0.004 (2)0.000 (2)
C30.056 (3)0.028 (2)0.054 (3)0.000 (2)−0.003 (2)−0.008 (2)
C40.042 (2)0.024 (2)0.052 (3)0.0039 (18)−0.005 (2)−0.007 (2)
C50.044 (2)0.023 (2)0.043 (3)0.0005 (19)0.0009 (19)−0.0030 (19)
C60.043 (3)0.050 (3)0.056 (3)0.001 (2)0.000 (2)0.008 (3)
C70.053 (3)0.045 (3)0.081 (4)−0.002 (3)−0.005 (3)−0.001 (3)
C80.058 (3)0.084 (5)0.095 (4)−0.019 (3)0.014 (3)0.004 (4)
C90.083 (4)0.055 (4)0.070 (4)−0.020 (3)−0.028 (3)−0.010 (3)
C100.099 (5)0.080 (5)0.071 (4)−0.022 (4)−0.034 (4)−0.001 (3)
C110.060 (3)0.058 (4)0.045 (3)0.028 (3)−0.006 (3)−0.018 (3)
C120.062 (3)0.096 (5)0.075 (4)0.023 (3)0.020 (3)0.005 (4)
C130.076 (4)0.039 (3)0.058 (3)0.024 (3)−0.018 (3)−0.012 (3)
C140.070 (4)0.066 (4)0.117 (6)0.025 (3)−0.019 (4)−0.028 (4)
C150.041 (2)0.032 (2)0.048 (3)0.004 (2)−0.003 (2)−0.007 (2)
C160.069 (3)0.032 (3)0.052 (3)0.002 (2)−0.013 (3)0.003 (2)
C170.069 (3)0.053 (3)0.048 (3)−0.002 (3)−0.023 (2)0.002 (3)
C180.054 (3)0.030 (2)0.048 (3)−0.001 (2)−0.005 (2)−0.010 (2)
C190.062 (3)0.035 (3)0.057 (3)0.000 (2)−0.013 (2)−0.004 (2)
C200.062 (3)0.035 (3)0.048 (3)−0.008 (2)−0.018 (2)−0.003 (2)
C210.060 (3)0.040 (3)0.050 (3)0.003 (2)−0.015 (2)−0.009 (2)
C220.076 (3)0.047 (3)0.053 (3)−0.004 (3)−0.016 (3)0.007 (3)
Geometric parameters (Å, °) top
S1—C221.693 (6)C4—H40.9800
O1—C71.330 (6)C5—H50.9800
O1—C61.435 (6)C6—H6A0.9700
O2—C71.210 (7)C6—H6B0.9700
O3—C91.336 (6)C7—C81.510 (8)
O3—C21.448 (6)C8—H8A0.9600
O4—C91.207 (7)C8—H8B0.9600
O5—C111.333 (6)C8—H8C0.9600
O5—C31.452 (6)C9—C101.477 (8)
O6—C111.204 (7)C10—H10A0.9600
O7—C131.349 (6)C10—H10B0.9600
O7—C41.432 (6)C10—H10C0.9600
O8—C131.201 (7)C11—C121.485 (8)
O9—C51.401 (5)C12—H12A0.9600
O9—C151.404 (5)C12—H12B0.9600
O10—C51.422 (5)C12—H12C0.9600
O10—C11.442 (5)C13—C141.501 (8)
N1—C211.271 (6)C14—H14A0.9600
N1—N21.386 (6)C14—H14B0.9600
N2—C221.336 (7)C14—H14C0.9600
N2—H2N10.75 (5)C15—C161.374 (7)
N3—C221.307 (7)C15—C201.376 (7)
N3—H3A0.8600C16—C171.387 (7)
N3—H3B0.8600C16—H160.9300
C1—C21.516 (6)C17—C181.380 (7)
C1—C61.518 (6)C17—H170.9300
C1—H10.9800C18—C191.391 (7)
C2—C31.512 (7)C18—C211.477 (7)
C2—H20.9800C19—C201.397 (7)
C3—C41.536 (6)C19—H190.9300
C3—H30.9800C20—H200.9300
C4—C51.517 (6)C21—H210.9300
C7—O1—C6119.3 (4)C7—C8—H8C109.5
C9—O3—C2118.3 (4)H8A—C8—H8C109.5
C11—O5—C3119.4 (4)H8B—C8—H8C109.5
C13—O7—C4117.1 (4)O4—C9—O3122.3 (5)
C5—O9—C15117.6 (3)O4—C9—C10126.7 (5)
C5—O10—C1114.0 (3)O3—C9—C10111.0 (5)
C21—N1—N2114.1 (4)C9—C10—H10A109.5
C22—N2—N1120.7 (5)C9—C10—H10B109.5
C22—N2—H2N1121 (4)H10A—C10—H10B109.5
N1—N2—H2N1117 (4)C9—C10—H10C109.5
C22—N3—H3A120.0H10A—C10—H10C109.5
C22—N3—H3B120.0H10B—C10—H10C109.5
H3A—N3—H3B120.0O6—C11—O5122.3 (6)
O10—C1—C2108.3 (4)O6—C11—C12125.2 (5)
O10—C1—C6107.5 (4)O5—C11—C12112.5 (5)
C2—C1—C6118.2 (4)C11—C12—H12A109.5
O10—C1—H1107.5C11—C12—H12B109.5
C2—C1—H1107.5H12A—C12—H12B109.5
C6—C1—H1107.5C11—C12—H12C109.5
O3—C2—C3111.4 (4)H12A—C12—H12C109.5
O3—C2—C1106.3 (4)H12B—C12—H12C109.5
C3—C2—C1110.1 (4)O8—C13—O7122.0 (5)
O3—C2—H2109.7O8—C13—C14126.6 (5)
C3—C2—H2109.7O7—C13—C14111.4 (5)
C1—C2—H2109.7C13—C14—H14A109.5
O5—C3—C2107.4 (4)C13—C14—H14B109.5
O5—C3—C4106.5 (4)H14A—C14—H14B109.5
C2—C3—C4108.9 (4)C13—C14—H14C109.5
O5—C3—H3111.3H14A—C14—H14C109.5
C2—C3—H3111.3H14B—C14—H14C109.5
C4—C3—H3111.3C16—C15—C20121.7 (4)
O7—C4—C5107.9 (3)C16—C15—O9115.3 (4)
O7—C4—C3110.2 (4)C20—C15—O9123.0 (4)
C5—C4—C3108.9 (4)C15—C16—C17118.8 (5)
O7—C4—H4109.9C15—C16—H16120.6
C5—C4—H4109.9C17—C16—H16120.6
C3—C4—H4109.9C18—C17—C16121.2 (4)
O9—C5—O10107.5 (3)C18—C17—H17119.4
O9—C5—C4108.6 (3)C16—C17—H17119.4
O10—C5—C4108.9 (3)C17—C18—C19119.0 (4)
O9—C5—H5110.6C17—C18—C21118.9 (4)
O10—C5—H5110.6C19—C18—C21122.1 (4)
C4—C5—H5110.6C18—C19—C20120.4 (5)
O1—C6—C1112.3 (4)C18—C19—H19119.8
O1—C6—H6A109.1C20—C19—H19119.8
C1—C6—H6A109.1C15—C20—C19118.8 (4)
O1—C6—H6B109.1C15—C20—H20120.6
C1—C6—H6B109.1C19—C20—H20120.6
H6A—C6—H6B107.9N1—C21—C18122.0 (4)
O2—C7—O1122.4 (5)N1—C21—H21119.0
O2—C7—C8127.4 (5)C18—C21—H21119.0
O1—C7—C8110.2 (5)N3—C22—N2118.0 (5)
C7—C8—H8A109.5N3—C22—S1123.5 (5)
C7—C8—H8B109.5N2—C22—S1118.5 (4)
H8A—C8—H8B109.5
C21—N1—N2—C22−171.8 (6)C7—O1—C6—C1−102.7 (5)
C5—O10—C1—C261.6 (4)O10—C1—C6—O1−43.1 (5)
C5—O10—C1—C6−169.7 (3)C2—C1—C6—O179.8 (5)
C9—O3—C2—C384.1 (5)C6—O1—C7—O212.4 (8)
C9—O3—C2—C1−156.0 (4)C6—O1—C7—C8−166.7 (4)
O10—C1—C2—O3−178.4 (3)C2—O3—C9—O4−9.7 (9)
C6—C1—C2—O359.1 (5)C2—O3—C9—C10173.3 (5)
O10—C1—C2—C3−57.6 (5)C3—O5—C11—O66.7 (7)
C6—C1—C2—C3179.9 (4)C3—O5—C11—C12−172.2 (4)
C11—O5—C3—C2−141.7 (4)C4—O7—C13—O8−1.1 (7)
C11—O5—C3—C4101.7 (5)C4—O7—C13—C14−180.0 (5)
O3—C2—C3—O560.0 (5)C5—O9—C15—C16−161.2 (4)
C1—C2—C3—O5−57.7 (5)C5—O9—C15—C2018.6 (6)
O3—C2—C3—C4174.9 (4)C20—C15—C16—C17−0.1 (8)
C1—C2—C3—C457.2 (5)O9—C15—C16—C17179.8 (5)
C13—O7—C4—C5154.5 (4)C15—C16—C17—C180.7 (8)
C13—O7—C4—C3−86.7 (5)C16—C17—C18—C19−0.9 (8)
O5—C3—C4—O7−59.8 (4)C16—C17—C18—C21178.5 (5)
C2—C3—C4—O7−175.3 (4)C17—C18—C19—C200.3 (8)
O5—C3—C4—C558.4 (4)C21—C18—C19—C20−179.0 (5)
C2—C3—C4—C5−57.2 (5)C16—C15—C20—C19−0.4 (8)
C15—O9—C5—O10−79.8 (4)O9—C15—C20—C19179.7 (5)
C15—O9—C5—C4162.5 (4)C18—C19—C20—C150.3 (8)
C1—O10—C5—O9180.0 (3)N2—N1—C21—C18178.3 (5)
C1—O10—C5—C4−62.5 (4)C17—C18—C21—N1−171.7 (5)
O7—C4—C5—O9−65.2 (4)C19—C18—C21—N17.6 (8)
C3—C4—C5—O9175.2 (4)N1—N2—C22—N3−3.1 (9)
O7—C4—C5—O10178.1 (3)N1—N2—C22—S1174.7 (4)
C3—C4—C5—O1058.5 (4)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2N1···O10i0.75 (5)2.33 (5)3.076 (6)172 (6)
N3—H3A···O8ii0.862.603.229 (7)131
Symmetry codes: (i) x+1/2, −y+1/2, −z+2; (ii) x, y+1, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2N1···O10i0.75 (5)2.33 (5)3.076 (6)172 (6)
N3—H3A···O8ii0.862.603.229 (7)131
Symmetry codes: (i) x+1/2, −y+1/2, −z+2; (ii) x, y+1, z.
Acknowledgements top

The authors thank Mr Zhi-Hua Mao of Sichuan University for the X-ray data collection.

references
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