organic compounds
1-Deoxy-1-(N-methyl-4-fluorophenylamino)-D-arabino-hexulose
aDepartment of Biochemistry, University of Missouri, Columbia, MO65211, USA, bDepartment of Chemistry, University of Missouri, Columbia, MO65211, USA, and cDepartment of Biochemistry, University of Missouri, Columbia, MO 65211, USA
*Correspondence e-mail: mossinev@missouri.edu
The title compound, C13H18FNO5, consists of D-fructose with an aromatic amine. The carbohydrate chain is in the acyclic keto form and has the zigzag conformation, while the solid-state NMR data suggests a conformational dimorphism at the aromatic amine group. The carbohydrate portion is involved in extensive O—H⋯O hydrogen bonding, which forms a two-dimensional network parallel to (001) and organized into fused homodromic ring patterns. The Hirshfeld surface fingerprint plots reveal a major contribution of the non-polar H⋯H and C⋯H interactions to the crystal packing forces.
Keywords: crystal structure; D-fructosamine; acyclic carbohydrate; hydrogen bonding.
CCDC reference: 753227
Structure description
The molecular structure and atomic numbering for the title compound (I) are shown in Fig. 1. The molecule is an Amadori rearrangement product (Feather & Mossine, 1998) and can be viewed as a conjugate of a carbohydrate, 1-amino-1-deoxy-D-fructose, and an aromatic amine, N-methyl-p-fluoroaniline, which are joined through the common amino nitrogen atom. The carbohydrate moiety in (I) exists in the acyclic keto form. Notably, in the aqueous solution of (I), this tautomeric form is a minor constituent of the equilibrium, at 9.4% of the total population [Supplementary Table 1S; includes references Gomez de Anderez et al. (1996) and Mossine et al. (2009b)]. The acyclic carbohydrate is in the zigzag conformation, having five out of six of its carbon atoms, C2, C3, C4, C5, and C6, located in one plane. The conformation around the carbonyl group is also nearly flat and involves atoms N1, C1, C2, O2, C3, and O3, with the carbonyl O2 atom in a close to a syn-periplanar position in respect to both N1 and O3 [respective torsion angles are 8.2 (5) and 9.4 (5)°]. The tertiary amino group geometry is a flattened pyramid, with the distance from the N1 apex to the C1–C7–C13 base of 0.248 (3) Å and the average base–face dihedral angle of 19.3 (4)°. The N1—C7 distance, at 1.409 (4) Å, is significantly shorter than the distances from N1 to the aliphatic carbon atoms C1 and C13 [1.452 (4) and 1.465 (5) Å], which is an indication for a mixed sp3/sp2 at N1 and a partial resonance of the nitrogen p-electrons with the neighboring benzene ring. In the solid-state NMR spectrum of powdered (I) (Fig. 2), the peaks corresponding to C1, C7, C10, and C13 are split at about a 1:2 ratio, indicating the presence of crystals with two different conformations of (I) at the aromatic amine, likely due to configurational inversion at the amino atom N1.
The molecular packing of (I) features alternating `carbohydrate' and `hydrocarbon' layers propagating in the ab plane (Fig. 3). The carbohydrate residues form a two-dimensional network of hydrogen bonds (Table 1) organized as a system of two infinite chains, with the ⋯O3—H⋯O5–H⋯ and the ⋯O4—H⋯O6—H⋯ sequences of intermolecular hydrogen bonds. These chains are connected by the intramolecular short heteroatom contacts O3—H⋯O4 and O6—H⋯O5. Basic hydrogen-bonding patterns of the resulting network are depicted in Fig. 4 and include fused homodromic rings. In addition, there are close C—H⋯A contacts within the `hydrocarbon' layer that may qualify as weak hydrogen bonds (Table 2). The Hirshfeld surface analysis (Spackman & Jayatilaka, 2009) revealed that a major proportion of the intermolecular contacts in of (I) is provided by non- or low-polar interactions of the H⋯H and C⋯H type (Fig. 5 and Table 3).
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Synthesis and crystallization
The preparation of (I) has been described previously (Mossine et al., 2009). Briefly, a mixture of 0.02 moles of D-glucose, 0.022 moles of N-methyl-p-fluoroaniline and 0.55 ml of acetic acid catalyst was stirred for 6 h in 8 ml of 2-propanol at 360 K. The purification step included ion-exchange on Amberlite IRN-77 (H+), with 0.2 M NH4OH in 50% ethanol as an eluant, and was followed by flash filtration on a short silica column using 5% MeOH in CH2Cl2 as an eluant. Crystals suitable for the diffraction study were obtained from of (I) in water/methanol (1:4) following addition a few drops of acetone at 277 K. See Fig. 2 for the solid-state NMR spectrum of (I).
Refinement
Crystal data, data collection and structure . As a result of the unrealistic value obtained for the Flack parameter [0.2 (10) for 474 quotients; Parsons et al., 2013], the of the chain system (3S,4R,5R) was assigned on the basis of the known configuration for starting D-glucose (McNaught, 1996).
details are summarized in Table 4
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Structural data
CCDC reference: 753227
https://doi.org/10.1107/S2414314618003693/lh4033sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618003693/lh4033Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314618003693/lh4033Isup3.cml
Data collection: SMART (Bruker, 1998); cell
SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015); molecular graphics: X-SEED (Barbour, 2001) and Mercury (Macrae et al., 2008); software used to prepare material for publication: CIFTAB (Sheldrick, 2008) and publCIF (Westrip, 2010).C13H18FNO5 | F(000) = 304 |
Mr = 287.28 | Dx = 1.401 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
a = 10.561 (6) Å | Cell parameters from 1387 reflections |
b = 5.156 (3) Å | θ = 2.5–24.4° |
c = 12.504 (7) Å | µ = 0.12 mm−1 |
β = 90.606 (9)° | T = 100 K |
V = 680.9 (6) Å3 | Needle, colourless |
Z = 2 | 0.50 × 0.10 × 0.05 mm |
Bruker APEXII CCD area detector diffractometer | 1588 reflections with I > 2σ(I) |
ω scans | Rint = 0.039 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | θmax = 27.2°, θmin = 1.6° |
Tmin = 0.79, Tmax = 0.99 | h = −13→13 |
4693 measured reflections | k = −6→6 |
2652 independent reflections | l = −15→14 |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H atoms treated by a mixture of independent and constrained refinement |
R[F2 > 2σ(F2)] = 0.042 | w = 1/[σ2(Fo2) + (0.0463P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.100 | (Δ/σ)max < 0.001 |
S = 0.95 | Δρmax = 0.18 e Å−3 |
2652 reflections | Δρmin = −0.16 e Å−3 |
198 parameters | Absolute structure: Flack x determined using 474 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
1 restraint | Absolute structure parameter: 0.2 (10) |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
Refinement. Hydroxy and nitrogen-bound H-atoms were located in difference-Fourier analyses and were allowed to refine fully. Other H atoms were placed at calculated positions and treated as riding, with C—H = 0.98 Å (methyl), 0.99 Å (methylene) or 1.00 Å (methine) and with Uiso(H) = 1.2Ueq(methine or methylene) or 1.5Ueq(methyl). |
x | y | z | Uiso*/Ueq | ||
F1 | 0.0320 (2) | 0.1152 (6) | −0.2413 (2) | 0.0782 (9) | |
N1 | 0.3656 (3) | 0.1754 (6) | 0.1042 (2) | 0.0343 (8) | |
C1 | 0.3239 (4) | 0.2826 (7) | 0.2053 (3) | 0.0374 (10) | |
H1A | 0.277228 | 0.445581 | 0.190761 | 0.045* | |
H1B | 0.399564 | 0.327236 | 0.248943 | 0.045* | |
O2 | 0.2218 (2) | −0.1203 (5) | 0.2449 (2) | 0.0472 (8) | |
C2 | 0.2394 (3) | 0.1037 (8) | 0.2706 (3) | 0.0329 (9) | |
O3 | 0.0910 (2) | 0.0429 (5) | 0.4150 (2) | 0.0375 (7) | |
C3 | 0.1810 (3) | 0.2174 (7) | 0.3703 (3) | 0.0323 (10) | |
H3 | 0.135141 | 0.379624 | 0.349283 | 0.039* | |
O4 | 0.3611 (2) | 0.0655 (5) | 0.4743 (2) | 0.0364 (7) | |
C4 | 0.2844 (3) | 0.2909 (7) | 0.4525 (3) | 0.0289 (9) | |
H4 | 0.338661 | 0.431473 | 0.422352 | 0.035* | |
O5 | 0.1544 (2) | 0.6087 (5) | 0.5363 (2) | 0.0360 (7) | |
C5 | 0.2283 (3) | 0.3818 (8) | 0.5579 (3) | 0.0323 (9) | |
H5 | 0.171498 | 0.242944 | 0.585874 | 0.039* | |
O6 | 0.4085 (2) | 0.6539 (5) | 0.6102 (2) | 0.0387 (7) | |
C6 | 0.3272 (3) | 0.4450 (7) | 0.6423 (3) | 0.0383 (10) | |
H6A | 0.284356 | 0.493149 | 0.709461 | 0.046* | |
H6B | 0.379111 | 0.288784 | 0.656630 | 0.046* | |
C7 | 0.2775 (3) | 0.1567 (7) | 0.0191 (3) | 0.0318 (8) | |
C8 | 0.1716 (4) | 0.3148 (9) | 0.0110 (3) | 0.0479 (11) | |
H8 | 0.155226 | 0.435436 | 0.066554 | 0.058* | |
C9 | 0.0895 (4) | 0.3024 (10) | −0.0752 (4) | 0.0551 (12) | |
H9 | 0.017345 | 0.412140 | −0.078552 | 0.066* | |
C10 | 0.1128 (4) | 0.1321 (9) | −0.1549 (3) | 0.0511 (12) | |
C11 | 0.2163 (5) | −0.0204 (10) | −0.1523 (4) | 0.0669 (14) | |
H11 | 0.232965 | −0.135503 | −0.209800 | 0.080* | |
C12 | 0.2978 (4) | −0.0084 (9) | −0.0658 (3) | 0.0605 (14) | |
H12 | 0.370320 | −0.117390 | −0.064489 | 0.073* | |
C13 | 0.4626 (3) | −0.0266 (8) | 0.1133 (3) | 0.0425 (10) | |
H13A | 0.421826 | −0.197004 | 0.117209 | 0.064* | |
H13B | 0.513541 | 0.002372 | 0.178204 | 0.064* | |
H13C | 0.517502 | −0.020370 | 0.050643 | 0.064* | |
H4O | 0.438 (5) | 0.077 (13) | 0.438 (4) | 0.11 (2)* | |
H5O | 0.078 (4) | 0.584 (9) | 0.556 (3) | 0.055 (13)* | |
H3O | 0.129 (4) | −0.090 (10) | 0.434 (3) | 0.055 (15)* | |
H6O | 0.363 (5) | 0.753 (10) | 0.570 (4) | 0.09 (2)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
F1 | 0.0717 (17) | 0.100 (2) | 0.0620 (16) | −0.0097 (17) | −0.0238 (14) | 0.0038 (16) |
N1 | 0.0397 (17) | 0.0258 (18) | 0.0377 (18) | 0.0002 (15) | 0.0064 (15) | −0.0010 (14) |
C1 | 0.045 (2) | 0.026 (2) | 0.041 (2) | −0.0094 (18) | 0.0030 (19) | −0.0010 (18) |
O2 | 0.0494 (16) | 0.0234 (16) | 0.069 (2) | −0.0055 (13) | 0.0165 (14) | −0.0069 (14) |
C2 | 0.0263 (17) | 0.024 (2) | 0.049 (2) | 0.0029 (16) | 0.0035 (16) | 0.0002 (18) |
O3 | 0.0253 (14) | 0.0256 (16) | 0.0617 (19) | −0.0006 (13) | 0.0072 (12) | 0.0028 (14) |
C3 | 0.0248 (19) | 0.024 (2) | 0.048 (2) | 0.0000 (16) | 0.0065 (18) | 0.0017 (18) |
O4 | 0.0296 (14) | 0.0230 (14) | 0.0567 (17) | 0.0060 (12) | 0.0045 (13) | 0.0045 (13) |
C4 | 0.0283 (19) | 0.021 (2) | 0.038 (2) | 0.0018 (16) | 0.0031 (18) | 0.0015 (17) |
O5 | 0.0238 (14) | 0.0235 (15) | 0.0610 (18) | 0.0018 (12) | 0.0113 (12) | 0.0009 (13) |
C5 | 0.0238 (19) | 0.023 (2) | 0.050 (3) | 0.0015 (17) | 0.0074 (18) | 0.0058 (18) |
O6 | 0.0283 (14) | 0.0366 (18) | 0.0513 (17) | −0.0062 (13) | −0.0005 (13) | 0.0044 (14) |
C6 | 0.038 (2) | 0.028 (3) | 0.048 (3) | −0.0034 (18) | 0.007 (2) | 0.0000 (19) |
C7 | 0.0326 (19) | 0.024 (2) | 0.039 (2) | −0.0036 (17) | 0.0006 (17) | 0.0017 (18) |
C8 | 0.051 (3) | 0.046 (3) | 0.047 (3) | 0.017 (2) | 0.003 (2) | −0.009 (2) |
C9 | 0.046 (3) | 0.065 (3) | 0.055 (3) | 0.017 (2) | 0.002 (2) | 0.005 (3) |
C10 | 0.048 (3) | 0.059 (3) | 0.046 (3) | −0.008 (2) | −0.011 (2) | 0.007 (2) |
C11 | 0.084 (3) | 0.059 (3) | 0.057 (3) | 0.008 (3) | −0.015 (3) | −0.023 (3) |
C12 | 0.065 (3) | 0.046 (3) | 0.069 (3) | 0.024 (2) | −0.018 (3) | −0.019 (3) |
C13 | 0.034 (2) | 0.042 (2) | 0.051 (3) | 0.0066 (19) | 0.0051 (19) | 0.004 (2) |
F1—C10 | 1.373 (4) | C5—C6 | 1.512 (5) |
N1—C7 | 1.409 (4) | C5—H5 | 1.0000 |
N1—C1 | 1.452 (4) | O6—C6 | 1.437 (4) |
N1—C13 | 1.465 (5) | O6—H6O | 0.86 (5) |
C1—C2 | 1.527 (5) | C6—H6A | 0.9900 |
C1—H1A | 0.9900 | C6—H6B | 0.9900 |
C1—H1B | 0.9900 | C7—C12 | 1.379 (5) |
O2—C2 | 1.213 (4) | C7—C8 | 1.387 (5) |
C2—C3 | 1.515 (5) | C8—C9 | 1.377 (5) |
O3—C3 | 1.427 (4) | C8—H8 | 0.9500 |
O3—H3O | 0.83 (5) | C9—C10 | 1.353 (6) |
C3—C4 | 1.539 (5) | C9—H9 | 0.9500 |
C3—H3 | 1.0000 | C10—C11 | 1.347 (6) |
O4—C4 | 1.441 (4) | C11—C12 | 1.377 (6) |
O4—H4O | 0.94 (6) | C11—H11 | 0.9500 |
C4—C5 | 1.524 (4) | C12—H12 | 0.9500 |
C4—H4 | 1.0000 | C13—H13A | 0.9800 |
O5—C5 | 1.431 (4) | C13—H13B | 0.9800 |
O5—H5O | 0.86 (4) | C13—H13C | 0.9800 |
C7—N1—C1 | 118.7 (3) | C4—C5—H5 | 108.8 |
C7—N1—C13 | 117.8 (3) | C6—O6—H6O | 106 (3) |
C1—N1—C13 | 114.9 (3) | O6—C6—C5 | 112.2 (3) |
N1—C1—C2 | 114.8 (3) | O6—C6—H6A | 109.2 |
N1—C1—H1A | 108.6 | C5—C6—H6A | 109.2 |
C2—C1—H1A | 108.6 | O6—C6—H6B | 109.2 |
N1—C1—H1B | 108.6 | C5—C6—H6B | 109.2 |
C2—C1—H1B | 108.6 | H6A—C6—H6B | 107.9 |
H1A—C1—H1B | 107.5 | C12—C7—C8 | 116.0 (4) |
O2—C2—C3 | 121.6 (3) | C12—C7—N1 | 121.1 (3) |
O2—C2—C1 | 121.5 (3) | C8—C7—N1 | 122.7 (3) |
C3—C2—C1 | 116.9 (3) | C9—C8—C7 | 122.0 (4) |
C3—O3—H3O | 108 (3) | C9—C8—H8 | 119.0 |
O3—C3—C2 | 110.9 (3) | C7—C8—H8 | 119.0 |
O3—C3—C4 | 111.4 (3) | C10—C9—C8 | 119.3 (4) |
C2—C3—C4 | 110.6 (3) | C10—C9—H9 | 120.4 |
O3—C3—H3 | 107.9 | C8—C9—H9 | 120.4 |
C2—C3—H3 | 107.9 | C11—C10—C9 | 121.0 (4) |
C4—C3—H3 | 107.9 | C11—C10—F1 | 118.7 (4) |
C4—O4—H4O | 110 (4) | C9—C10—F1 | 120.3 (4) |
O4—C4—C5 | 107.9 (3) | C10—C11—C12 | 119.5 (4) |
O4—C4—C3 | 108.7 (3) | C10—C11—H11 | 120.2 |
C5—C4—C3 | 111.9 (3) | C12—C11—H11 | 120.2 |
O4—C4—H4 | 109.4 | C11—C12—C7 | 122.1 (4) |
C5—C4—H4 | 109.4 | C11—C12—H12 | 118.9 |
C3—C4—H4 | 109.4 | C7—C12—H12 | 118.9 |
C5—O5—H5O | 110 (3) | N1—C13—H13A | 109.5 |
O5—C5—C6 | 109.1 (3) | N1—C13—H13B | 109.5 |
O5—C5—C4 | 107.7 (3) | H13A—C13—H13B | 109.5 |
C6—C5—C4 | 113.5 (3) | N1—C13—H13C | 109.5 |
O5—C5—H5 | 108.8 | H13A—C13—H13C | 109.5 |
C6—C5—H5 | 108.8 | H13B—C13—H13C | 109.5 |
C7—N1—C1—C2 | 73.7 (4) | O5—C5—C6—O6 | −58.2 (4) |
C13—N1—C1—C2 | −73.4 (4) | C4—C5—C6—O6 | 61.9 (4) |
N1—C1—C2—O2 | 8.2 (5) | C1—N1—C7—C12 | −160.5 (4) |
N1—C1—C2—C3 | −173.1 (3) | C13—N1—C7—C12 | −14.3 (5) |
O2—C2—C3—O3 | −9.4 (5) | C1—N1—C7—C8 | 24.7 (5) |
C1—C2—C3—O3 | 171.8 (3) | C13—N1—C7—C8 | 170.8 (4) |
O2—C2—C3—C4 | 114.7 (4) | C12—C7—C8—C9 | 1.9 (6) |
C1—C2—C3—C4 | −64.0 (4) | N1—C7—C8—C9 | 177.0 (4) |
O3—C3—C4—O4 | 68.4 (4) | C7—C8—C9—C10 | −0.4 (7) |
C2—C3—C4—O4 | −55.4 (4) | C8—C9—C10—C11 | −1.6 (7) |
O3—C3—C4—C5 | −50.7 (4) | C8—C9—C10—F1 | 179.7 (4) |
C2—C3—C4—C5 | −174.5 (3) | C9—C10—C11—C12 | 1.9 (7) |
O4—C4—C5—O5 | 178.8 (3) | F1—C10—C11—C12 | −179.3 (4) |
C3—C4—C5—O5 | −61.6 (3) | C10—C11—C12—C7 | −0.3 (7) |
O4—C4—C5—C6 | 58.0 (4) | C8—C7—C12—C11 | −1.5 (6) |
C3—C4—C5—C6 | 177.6 (3) | N1—C7—C12—C11 | −176.7 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3O···O5i | 0.83 (5) | 2.03 (5) | 2.782 (4) | 151 (4) |
O4—H4O···O6ii | 0.94 (6) | 1.78 (6) | 2.701 (4) | 167 (5) |
O5—H5O···O3iii | 0.86 (4) | 1.84 (4) | 2.690 (4) | 174 (4) |
O6—H6O···O4iv | 0.86 (5) | 2.01 (5) | 2.762 (4) | 146 (5) |
Symmetry codes: (i) x, y−1, z; (ii) −x+1, y−1/2, −z+1; (iii) −x, y+1/2, −z+1; (iv) x, y+1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3O···O4 | 0.86 (4) | 2.62 (3) | 2.940 (3) | 103 (3) |
O6—H6O···O5 | 0.86 (5) | 2.36 (5) | 2.839 (4) | 116 (4) |
C1—H1A···O2 | 0.99 | 2.41 | 3.299 (5) | 149 |
C3—H3···F1 | 1.00 | 2.52 | 3.432 (5) | 151 |
Symmetry codes: (i) x, y + 1, z; (ii) -x, y + 1/2, -z. |
Compound | Alkyl, aryl | O···H | H···H | C···H | Other contacts |
(I) | methyl, p-fluorophenyl | 26.3 | 44.6 | 13.5 | F···H 10.9; F···O 2.6; N···H 1.8; C···C 0.3 |
FruNMptia | methyl, p-methylphenyl | 26.5 | 59.8 | 11.8 | N···H 1.6; C···C 0.3 |
FruNMpasb | methyl, p-methoxyphenyl | 32.3 | 58.2 | 13.2 | N···H 1.6; C···C 0.1 |
FruNEpcaa | ethyl, p-chlorophenyl | 23.1 | 50.1 | 8.6 | Cl···H 13.1; Cl···C 3.4; N···C 0.5; C···C 1.3 |
FruNAllac | allyl, phenyl | 15.2 | 67.7 | 16.9 | C···C 0.1 |
References: (a) Mossine et al. (2009); (b) Mossine et al. (2018); (c) Mossine et al. (2009a). |
Compound | Amine substituents | Crystalline isomers | |||||
α-pyranose | β-pyranose | α-furanose | β-furanose | acyclic, keto | |||
(I) [a] | methyl, p-fluorophenyl | 2.5 | 52.1 | 5.0 | 31.0 | 9.4 | acyclic keto |
FruNMptia | methyl, p-methylphenyl | 2.1 | 49.9 | 4.8 | 32.2 | 11.0 | acyclic keto |
FruNMpasb | methyl, p-methoxyphenyl | 2.1 | 52.0 | 4.9 | 30.6 | 10.3 | acyclic keto |
FruNEpcaa | ethyl, p-chlorophenyl | 2.0 | 48.7 | 4.2 | 32.3 | 12.7 | acyclic keto |
Fruptia,c | H, phenyl | 3.5 | 61.0 | 9.4 | 24.2 | 1.9 | β-pyranose |
FruNAllad | allyl, phenyl | 2.2 | 47.4 | 4.5 | 33.6 | 12.3 | β-pyranose |
Fructosaminee | none | 5.0 | 70.8 | 11.2 | 12.3 | 0.8 | β-pyranose |
References: (a) Mossine et al. (2009); (b) Mossine et al. (2018); (c) Gomez de Anderez et al. (1996); (d) Mossine et al. (2009a); (e) Mossine et al. (2009b). |
Funding information
Funding for this research was provided by: University of Missouri Agriculture Experiment Station Chemical Laboratories; National Institute of Food and Agriculture (grant No. MO-HABC0002).
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