3,3′-(Ethane-1,2-diyl)bis(6-meth­oxy-3,4-dihydro-2H-1,3-benzoxazine) mono­hydrate

Rivera, A.; Camacho, J.; Ríos-Motta, J.; Kučeraková, M.; Dušek, M.

doi:10.1107/S1600536812035519

organic compounds

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doi:10.1107/S1600536812035519

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3,3′-(Ethane-1,2-diyl)bis(6-methoxy-3,4-dihydro-2H-1,3-benzoxazine) monohydrate

Augusto Rivera,^a ^* Jairo Camacho,^a Jaime Ríos-Motta,^a Monika Kučeraková ^b and Michal Dušek ^b

^aUniversidad Nacional de Colombia, Sede Bogotá, Facultad de Ciencias, Departamento de Química, Cra 30 No. 45-03, Bogotá, Código Postal 111321, Colombia, and ^bInstitute of Physics ASCR, v.v.i., Na Slovance 2, 182 21 Praha 8, Czech Republic
^*Correspondence e-mail: ariverau@unal.edu.co

(Received 9 August 2012; accepted 11 August 2012; online 23 August 2012)

The asymmetric unit of the title compound, C₂₀H₂₄N₂O₄·H₂O, contains one half-organic molecule (an inversion centre generates the other half of the molecule) and a half-molecule of water (the O atom has site symmetry 2). The near planarity of the fused-benzene ring is illustrated by the very small deviations of all the atoms from the plane [largest deviation = 0.0092 (11) Å. The six-membered N,O-containing ring adopts a half-chair conformation. The observed N—CH₂ and CH₂—O bond lengths can be correlated to the manifestation of an anomeric effect in the N—CH₂—O unit. In the crystal, the molecules are connected into zigzag chains parallel to [001] through O—H⋯N hydrogen bonds formed between the oxazinic N atom and the solvent water molecule. The chains are consolidated by C—H⋯O interactions.

Related literature

For related structures, see: Rivera et al. (2012 , 2011 , 2010 ). For the preparation of the title compound, see: Rivera et al. (1989 ). For ring conformations, see: Cremer & Pople (1975 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₂₀H₂₄N₂O₄·H₂O
M_r = 374.4
Monoclinic, C 2/c
a = 30.2999 (9) Å
b = 5.2132 (2) Å
c = 11.6058 (4) Å
β = 91.153 (2)°
V = 1832.87 (11) Å³
Z = 4
Cu Kα radiation
μ = 0.80 mm⁻¹
T = 120 K
0.17 × 0.13 × 0.13 mm

Data collection

Oxford Diffraction Xcalibur Atlas Gemini ultra diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012 ) T_min = 0.104, T_max = 1
18257 measured reflections
1639 independent reflections
1440 reflections with I > 3σ(I)
R_int = 0.033

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.094
S = 1.75
1639 reflections
127 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H1c4⋯O1ⁱ	0.96	2.46	3.2982 (13)	145.91
O3—H1o3⋯N1ⁱⁱ	0.914 (15)	2.076 (15)	2.9870 (12)	174.8 (13)
Symmetry codes: (i) $[x, -y, z-{\script{1\over 2}}]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: Superflip (Palatinus & Chapuis, 2007 ); program(s) used to refine structure: JANA2006 (Petříček et al., 2006 ); molecular graphics: DIAMOND (Brandenburg & Putz, 2005 ); software used to prepare material for publication: JANA2006.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812035519/bx2424sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812035519/bx2424Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812035519/bx2424Isup3.cml

checkCIF report

Comment top

As models to examine the anomeric effect we have recently studied the influence of substituent such as chlorine and methyl on 3,3'-ethane-1,2-diylbis(3,4-dihydro-2H-1,3-benzoxazine) (Rivera, et al., 2010; 2011; 2012). In order to continue this research, we have synthesized the title compound and obtained suitable crystals for single-crystal X-ray diffraction analysis.

The asymmetric unit of the title compound (Fig. 1), C₂₀H₂₄N₂O₄.H₂O, contains one half-organic molecule (an inversion centre generates the other half of the molecule) and one half water molecule The planarity of the fused-benzene ring is illustrated by very small deviation of all the atoms from these planes [largest deviations = 0.0092 (11) Å for C-3]. The half-chair conformation, with puckering parameters Q = 0.512 (2) Å, θ =129.6 (2)°, ϕ =283.6 (3)° (Cremer & Pople, 1975), of the six-membered N,O-containing ring is analyzed with respect to the plane formed by O1/C3/C5/C1 and the corresponding deviations of the atoms C9 and N1 are 0.3002 (11) and 0.3350 (10) Å, respectively. The methoxy substituent at the C6 atom forms the torsion angle of 2.63 (14) ° [synperiplanar conformation] with the atom set O2/C6/C8/C7. The bond lengths and angles are within normal ranges, whereas the C9—O1 bond length [1.4463 (13) Å] is shorter than the corresponding C—O bonds found in the chlorine related structure [1.529 (2) Å] (Rivera et al., 2010), whereas the N1—C9 bond length of [1.4445 (14) Å] is longer than the corresponding N—C bonds found in the related structure [1.3690 (16) Å] (Rivera et al., 2010). In contrast to the chloro analog, the title compound was found to be more agreement with other related structures (Rivera et al., 2012, 2011), and with the normal values for O—CH₂ (1.470) and CH₂—N (1.469) (Allen et al., 1987), indicating that the methoxy substituent decrease the influence of stereoelectronic effects in the N—CH₂—O moiety.

In the crystal structure, the molecules of the title compound are conected into zigzag chains parallel to [001] through O—H···N hydrogen bonds formed between its oxazinic N atom and the solvent water molecule. This chain is further stabilized by weak C—H···O hydrogen bonding interactions between H4 and O1. (Figure 2)

Related literature top

For related structures, see: Rivera et al. (2012, 2011, 2010). For the preparation of the title compound, see: Rivera et al. (1989). For ring conformations, see: Cremer & Pople (1975). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound was synthesized according to the literature procedure (Rivera et al.,1989), and the single crystals were obtained by slow evaporation from a ethanol/water solvent mixture at room temperature.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: Superflip (Palatinus & Chapuis, 2007); program(s) used to refine structure: JANA2006 (Petříček et al., 2006); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2006 (Petříček et al., 2006).

Figures top

A view of (I) with the numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. In the organic molecule, the labelled atoms are related with unlabelled atoms by symmetry code [1-x, 1-y, 1-z]. In the water molecule the labelled atom is related with unlabelled atom by symmetry code [1-x,y,3/2-z]. The hydrogen bond interaction is shown as dashed lines.

Packing of the molecules of the title compound view along the b axis. Intermolecular hydrogen bonds are shown as dashed lines. For clarity only shows the H atoms involved in hydrogen bonds.

3,3'-(Ethane-1,2-diyl)bis(6-methoxy-3,4-dihydro-2H-1,3-benzoxazine) monohydrate top

Crystal data top

C₂₀H₂₄N₂O₄·H₂O	F(000) = 800
M_r = 374.4	D_x = 1.357 Mg m⁻³
Monoclinic, C2/c	Cu Kα radiation, λ = 1.5418 Å
Hall symbol: -C 2yc	Cell parameters from 10577 reflections
a = 30.2999 (9) Å	θ = 2.9–67.0°
b = 5.2132 (2) Å	µ = 0.80 mm⁻¹
c = 11.6058 (4) Å	T = 120 K
β = 91.153 (2)°	Prism, white
V = 1832.87 (11) Å³	0.17 × 0.13 × 0.13 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur Atlas Gemini ultra diffractometer	1639 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source	1440 reflections with I > 3σ(I)
Mirror monochromator	R_int = 0.033
Detector resolution: 10.3784 pixels mm^-1	θ_max = 67.2°, θ_min = 2.9°
ω scans	h = −36→36
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	k = −6→6
T_min = 0.104, T_max = 1	l = −13→13
18257 measured reflections

Refinement top

Refinement on F²	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.030	Weighting scheme based on measured s.u.'s w = 1/(σ²(I) + 0.0016I²)
wR(F²) = 0.094	(Δ/σ)_max = 0.015
S = 1.75	Δρ_max = 0.17 e Å⁻³
1639 reflections	Δρ_min = −0.14 e Å⁻³
127 parameters	Extinction correction: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974)
0 restraints	Extinction coefficient: 1300 (300)
49 constraints

Crystal data top

C₂₀H₂₄N₂O₄·H₂O	V = 1832.87 (11) Å³
M_r = 374.4	Z = 4
Monoclinic, C2/c	Cu Kα radiation
a = 30.2999 (9) Å	µ = 0.80 mm⁻¹
b = 5.2132 (2) Å	T = 120 K
c = 11.6058 (4) Å	0.17 × 0.13 × 0.13 mm
β = 91.153 (2)°

Data collection top

Oxford Diffraction Xcalibur Atlas Gemini ultra diffractometer	1639 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	1440 reflections with I > 3σ(I)
T_min = 0.104, T_max = 1	R_int = 0.033
18257 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.094	H atoms treated by a mixture of independent and constrained refinement
S = 1.75	Δρ_max = 0.17 e Å⁻³
1639 reflections	Δρ_min = −0.14 e Å⁻³
127 parameters

Special details top

Refinement. The refinement was carried out against all reflections. The conventional R-factor is always based on F. The goodness of fit as well as the weighted R-factor are based on F and F² for refinement carried out on F and F², respectively. The threshold expression is used only for calculating R-factors etc. and it is not relevant to the choice of reflections for refinement.

The program used for refinement, Jana2006, uses the weighting scheme based on the experimental expectations, see _refine_ls_weighting_details, that does not force S to be one. Therefore the values of S are usually larger than the ones from the SHELX program.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.90016 (2)	0.11497 (15)	0.06702 (6)	0.0199 (2)
O2	0.80451 (3)	−0.57728 (15)	−0.19811 (7)	0.0218 (3)
O3	0.5	0.0044 (2)	0.25	0.0278 (4)
N1	0.95328 (3)	0.15870 (18)	−0.08373 (7)	0.0175 (3)
C1	0.92150 (3)	0.0638 (2)	−0.17210 (9)	0.0187 (3)
C2	0.98132 (3)	−0.0506 (2)	−0.03816 (9)	0.0185 (3)
C3	0.87593 (3)	−0.0523 (2)	−0.00091 (9)	0.0170 (3)
C4	0.85915 (3)	−0.2627 (2)	−0.18039 (9)	0.0170 (3)
C5	0.88428 (3)	−0.0852 (2)	−0.11834 (9)	0.0164 (3)
C6	0.82677 (3)	−0.4068 (2)	−0.12743 (9)	0.0177 (3)
C7	0.84416 (4)	−0.1983 (2)	0.05238 (9)	0.0198 (3)
C8	0.81931 (4)	−0.3764 (2)	−0.01008 (10)	0.0200 (3)
C9	0.92843 (3)	0.2868 (2)	0.00424 (9)	0.0179 (3)
C10	0.77298 (4)	−0.7400 (2)	−0.14564 (10)	0.0260 (4)
H1c1	0.936552	−0.044083	−0.225599	0.0225*
H2c1	0.909537	0.206326	−0.214813	0.0225*
H1c2	0.993326	−0.145584	−0.101079	0.0222*
H2c2	0.963614	−0.167436	0.005101	0.0222*
H1c4	0.864263	−0.286099	−0.261076	0.0205*
H1c7	0.839223	−0.176396	0.13323	0.0237*
H1c8	0.79727	−0.477366	0.027191	0.024*
H1c9	0.948384	0.371178	0.05716	0.0215*
H2c9	0.910924	0.420868	−0.030257	0.0215*
H1c10	0.76001	−0.851305	−0.20284	0.0312*
H2c10	0.787328	−0.841082	−0.086776	0.0312*
H3c10	0.750337	−0.637226	−0.111909	0.0312*
H1o3	0.4874 (5)	0.112 (3)	0.3020 (13)	0.0334*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0221 (4)	0.0216 (5)	0.0160 (4)	−0.0038 (3)	0.0011 (3)	−0.0019 (3)
O2	0.0213 (4)	0.0237 (5)	0.0205 (4)	−0.0064 (3)	−0.0002 (3)	−0.0021 (3)
O3	0.0369 (7)	0.0197 (7)	0.0274 (6)	0	0.0112 (5)	0
N1	0.0171 (4)	0.0186 (5)	0.0167 (4)	−0.0008 (4)	−0.0019 (3)	−0.0001 (4)
C1	0.0183 (5)	0.0233 (6)	0.0146 (5)	−0.0022 (5)	−0.0014 (4)	0.0015 (4)
C2	0.0173 (5)	0.0175 (6)	0.0208 (6)	0.0007 (4)	−0.0013 (4)	−0.0009 (4)
C3	0.0168 (5)	0.0171 (6)	0.0171 (6)	0.0027 (4)	−0.0018 (4)	−0.0008 (4)
C4	0.0174 (5)	0.0197 (6)	0.0140 (5)	0.0027 (4)	−0.0007 (4)	0.0007 (4)
C5	0.0151 (5)	0.0175 (6)	0.0166 (5)	0.0025 (4)	−0.0010 (4)	0.0034 (4)
C6	0.0161 (5)	0.0173 (6)	0.0196 (6)	0.0017 (4)	−0.0026 (4)	0.0001 (4)
C7	0.0209 (5)	0.0235 (6)	0.0150 (5)	0.0018 (5)	0.0022 (4)	0.0008 (4)
C8	0.0182 (5)	0.0212 (6)	0.0208 (6)	−0.0011 (4)	0.0031 (4)	0.0033 (4)
C9	0.0179 (5)	0.0162 (6)	0.0195 (5)	−0.0004 (4)	−0.0004 (4)	0.0000 (4)
C10	0.0249 (6)	0.0251 (7)	0.0279 (6)	−0.0096 (5)	−0.0007 (5)	0.0007 (5)

Geometric parameters (Å, º) top

O1—C3	1.3776 (13)	C3—C5	1.4016 (15)
O1—C9	1.4463 (13)	C3—C7	1.3827 (15)
O2—C6	1.3765 (13)	C4—C5	1.3902 (15)
O2—C10	1.4234 (15)	C4—C6	1.3890 (15)
O3—H1o3	0.914 (15)	C4—H1c4	0.96
O3—H1o3ⁱ	0.914 (15)	C6—C8	1.3941 (15)
N1—C1	1.4780 (13)	C7—C8	1.3903 (16)
N1—C2	1.4743 (14)	C7—H1c7	0.96
N1—C9	1.4445 (14)	C8—H1c8	0.96
C1—C5	1.5143 (15)	C9—H1c9	0.96
C1—H1c1	0.96	C9—H2c9	0.96
C1—H2c1	0.96	C10—H1c10	0.96
C2—C2ⁱⁱ	1.5181 (14)	C10—H2c10	0.96
C2—H1c2	0.96	C10—H3c10	0.96
C2—H2c2	0.96

C3—O1—C9	114.70 (8)	C1—C5—C3	119.23 (9)
C6—O2—C10	117.04 (8)	C1—C5—C4	122.19 (9)
H1o3—O3—H1o3ⁱ	104.2 (14)	C3—C5—C4	118.52 (10)
C1—N1—C2	111.35 (9)	O2—C6—C4	115.30 (9)
C1—N1—C9	107.66 (8)	O2—C6—C8	124.65 (10)
C2—N1—C9	113.16 (8)	C4—C6—C8	120.04 (10)
N1—C1—C5	111.48 (8)	C3—C7—C8	120.60 (10)
N1—C1—H1c1	109.47	C3—C7—H1c7	119.7
N1—C1—H2c1	109.47	C8—C7—H1c7	119.7
C5—C1—H1c1	109.47	C6—C8—C7	119.25 (10)
C5—C1—H2c1	109.47	C6—C8—H1c8	120.38
H1c1—C1—H2c1	107.39	C7—C8—H1c8	120.38
N1—C2—C2ⁱⁱ	111.70 (9)	O1—C9—N1	113.10 (9)
N1—C2—H1c2	109.47	O1—C9—H1c9	109.47
N1—C2—H2c2	109.47	O1—C9—H2c9	109.47
C2ⁱⁱ—C2—H1c2	109.47	N1—C9—H1c9	109.47
C2ⁱⁱ—C2—H2c2	109.47	N1—C9—H2c9	109.47
H1c2—C2—H2c2	107.15	H1c9—C9—H2c9	105.58
O1—C3—C5	121.97 (9)	O2—C10—H1c10	109.47
O1—C3—C7	117.40 (9)	O2—C10—H2c10	109.47
C5—C3—C7	120.56 (10)	O2—C10—H3c10	109.47
C5—C4—C6	121.01 (10)	H1c10—C10—H2c10	109.47
C5—C4—H1c4	119.49	H1c10—C10—H3c10	109.47
C6—C4—H1c4	119.5	H2c10—C10—H3c10	109.47

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H1c4···O1ⁱⁱⁱ	0.96	2.46	3.2982 (13)	145.91
O3—H1o3···N1^iv	0.914 (15)	2.076 (15)	2.9870 (12)	174.8 (13)

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

Experimental details

Crystal data
Chemical formula	C₂₀H₂₄N₂O₄·H₂O
M_r	374.4
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	120
a, b, c (Å)	30.2999 (9), 5.2132 (2), 11.6058 (4)
β (°)	91.153 (2)
V (Å³)	1832.87 (11)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	0.80
Crystal size (mm)	0.17 × 0.13 × 0.13

Data collection
Diffractometer	Oxford Diffraction Xcalibur Atlas Gemini ultra diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2012)
T_min, T_max	0.104, 1
No. of measured, independent and observed [I > 3σ(I)] reflections	18257, 1639, 1440
R_int	0.033
(sin θ/λ)_max (Å⁻¹)	0.598

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.094, 1.75
No. of reflections	1639
No. of parameters	127
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.14

Computer programs: CrysAlis PRO (Agilent, 2012), Superflip (Palatinus & Chapuis, 2007), JANA2006 (Petříček et al., 2006), DIAMOND (Brandenburg & Putz, 2005).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H1c4···O1ⁱ	0.96	2.46	3.2982 (13)	145.91
O3—H1o3···N1ⁱⁱ	0.914 (15)	2.076 (15)	2.9870 (12)	174.8 (13)

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

Acknowledgements

We acknowledge the Dirección de Investigaciones, Sede Bogotá (DIB) de la Universidad Nacional de Colombia, for financial support of this work, as well as the Praemium Academiae project of the Academy of Sciences of the Czech Republic.

References

Agilent (2012). CrysAlis PRO. Agilent Technologies, Yarnton, England. Google Scholar
Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CrossRef Web of Science Google Scholar
Brandenburg, K. & Putz, H. (2005). DIAMOND Crystal Impact, Bonn, Germany. Google Scholar
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358. CrossRef CAS Web of Science Google Scholar
Palatinus, L. & Chapuis, G. (2007). J. Appl. Cryst. 40, 786–790. Web of Science CrossRef CAS IUCr Journals Google Scholar
Petříček, V., Dušek, M. & Palatinus, L. (2006). JANA2006. Institute of Physics, Prague, Czech Republic. Google Scholar
Rivera, A., Aguilar, Z., Clavijo, D. & Joseph-Nathan, P. (1989). Anal. Quim. 85, 9–10. CAS Google Scholar
Rivera, A., Camacho, J., Ríos-Motta, J., Fejfarová, K. & Dušek, M. (2012). Acta Cryst. E68, o148. Web of Science CSD CrossRef IUCr Journals Google Scholar
Rivera, A., Camacho, J., Ríos-Motta, J., Pojarová, M. & Dušek, M. (2011). Acta Cryst. E67, o2028. Web of Science CSD CrossRef IUCr Journals Google Scholar
Rivera, A., Rojas, J. J., Ríos-Motta, J., Dušek, M. & Fejfarová, K. (2010). Acta Cryst. E66, o1134. Web of Science CSD CrossRef IUCr Journals Google Scholar

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

3,3′-(Ethane-1,2-diyl)bis­(6-meth­­oxy-3,4-di­hydro-2H-1,3-benzoxazine) mono­hydrate

Related literature

Experimental

Crystal data

Data collection

Refinement

Supporting information

Acknowledgements

References

organic compounds

3,3′-(Ethane-1,2-diyl)bis(6-methoxy-3,4-dihydro-2H-1,3-benzoxazine) monohydrate