F.A. Alharthi et al.
Carbohydrate Research 502 (2021) 108281
69.6 (C2), 69.2 (C4), 53.0 (OCH3), 21.2 (3 x Ar-CH3), 20.8 (OAc), 20.6
Table 1
Crystal data and structure refinement data for 6.
(OAc), 20.5 (OAc). FTIR νmax/cmꢀ 1 1739 (C O stretch), 1375 (acyl C–O
–
–
stretch), 1210 (acyl C–O stretch), 1034 (alkoxy C–O stretch) cmꢀ 1; MS
m/z, HRMS calculated for C20H24O9KS: 479.0778, found 479.0773. Rf
Empirical formula
C13H15NaO6S
Formula weight
Temperature/K
Crystal system
Space group
a/Å
322.30
= 0.86 in Pet Ether/Ethyl Acetate 1:1. Melting Point = 121–123 ◦C. [
= ꢀ 12.4 (MeOH).
α]
D
150.00(10)
orthorhombic
P212121
6.0756(5)
7.9838(5)
29.091(2)
90
4.4. Sodium 1-thiotolyl D-glucuronate 5
b/Å
c/Å
◦
α
/
To 4 (0.5621 g, 1.27 mmol) under N2 atmosphere dissolved in
anhydrous MeOH (12 mL), sodium methoxide (25–30% w/w in MeOH,
0.23 mL) was added dropwise. The solution was then stirred at room
temperature for 2 h whereupon TLC (product Rf = 0.26, 100% EtOAc)
indicated completion. Amberlite IR-86 H-form ion exchange resin was
then added to the reaction flask to neutralize the solution. The solution
was then filtered and concentrated in vacuo to yield crude 5 as a brown
solid, which was then washed with MeOH. This is yielded product 5 as
off-white solid (0.2644 g, 0.86 mmol, 67%).
β/◦
90
γ/◦
90
Volume/Å3
Z
1411.10(18)
4
ρcalcg/cm3
1.517
μ
/mm1
0.284
F(000)
672.0
Crystal size/mm3
Radiation
0.35 × 0.3 × 0.09
MoKα (λ = 0.71073)
2Θ range for data collection/◦
Index ranges
5.292 to 50.684
1H NMR (MeOD, 400 MHz) δ 7.53 (d, J = 8.1 Hz, 2 H, Ar–H), 7.13 (d,
J = 8.2 Hz, 2 H, Ar–H), 4.89 (s, br, 3 H, –OH), 4.51 (d, J = 9.7 Hz, 1 H,
H1), 3.59 (d, J = 9.4 Hz, 1 H, H5), 3.47–3.39 (m, 2 H, H3, H4), 3.23 (t, J
= 9.5 Hz, 1 H, H2), 2.32 (s, 3 H, Ar-CH3). 13C NMR (MeOD, 100 MHz) δ
175.2 (C6), 137.4 (Ar), 132.5 (2 x Ar–H), 129.7 (2 x Ar–H), 129.4
(Ar–H), 88.8 (C1), 79.4 (C5), 78.1 (C3), 72.2 (C2), 72.0 (C4), 19.8
(ArCH3); Product Rf = 0.26, 100% EtOAc. Melting Point = 182–185 ◦C.
ꢀ 7 ≤ h ≤ 7, ꢀ 9 ≤ k ≤ 9, ꢀ 35 ≤ l ≤ 34
14711
Reflections collected
Independent reflections
Data/restraints/parameters
Goodness-of-fit on F2
2586 [Rint = 0.0711, Rsigma = 0.0498]
2586/3/194
1.104
Final R indexes [I ≥ 2
σ
(I)]
R1 = 0.0481, wR2 = 0.0926
R1 = 0.0544, wR2 = 0.0945
0.26/-0.33
Final R indexes [all data]
Largest diff. peak/hole/e Åꢀ 3
Flack parameter
0.03(7)
[α]D = ꢀ 36.1 (H2O).
4.5. Methyl 1-thiotolyl-β-D-glucopyranuronate 6
Table 2
Crystal data and structure refinement data for 5.
To thioglycoside 6 (6.400 g, 20.29 mmol) under N2 atmosphere
dissolved in anhydrous MeOH (280 mL), was added sodium methoxide
(25–30% w/w in MeOH, 2.5 mL, 43.73 mmol) dropwise. The solution
was then stirred at room temperature for 90 min, whereupon TLC
indicated completion of consumption of starting material. The reaction
was neutralized with Amberlite IR-120 H-form ion exchange, filtered
and concentrated to yield crude 6 as a brown solid which was purified
via silica gel chromatography (100% EtOAc) to furnish product 6 as an
off-white solid (3.1877 g, 10.20 mmol, 70%). Rf = 0.46 (100% EtOAc).
1H NMR (MeOD, 400 MHz) δ 7.43 (d, J = 8.1 Hz, 2 H, Ar–H), 7.13 (d,
J = 7.9 Hz, 2 H, Ar–H), 4.56 (t, J = 9.6 Hz, 1 H, H1), 3.85 (d, J = 9.5 Hz,
1 H, H5), 3.79 (s, 3 H, –OCH3), 3.50 (t, J = 9.2 Hz, 1 H, H4), 3.38 (d, J =
8.8 Hz, 1 H, H3), 3.19 (app.t, J = 9.7 Hz, 1 H, H2), 2.3 (s, 1 H, Ar-CH3).
13C NMR (MeOD, 100 MHz) δ 169.5 (C6), 137.9 (Ar), 132.7 (2 x Ar–H),
129.2 (2 x Ar–H), 128.9 (Ar–H), 88.7 (C1), 78.9 (C5), 77.5 (C3), 71.9
(C2), 71.3 (C4), 51.4 (OCH3), 19.7 (ArCH3); ES MS m/z 337 (MNa+,
Empirical formula
C14H18O6S
Formula weight
Temperature/K
Crystal system
Space group
a/Å
314.34
100.00(10)
orthorhombic
P212121
5.82210(7)
8.10357(10)
31.2537(4)
90
b/Å
c/Å
◦
α
/
β/◦
90
γ/◦
90
Volume/Å3
Z
1474.54(3)
4
ρcalcg/cm3
1.416
μ
/mm1
2.188
F(000)
664.0
Crystal size/mm3
Radiation
0.153 × 0.129 × 0.119
Cu Kα (λ = 1.54184)
2Θ range for data collection/◦
Index ranges
5.656 to 152.278
100%); HRMS Calculated for
C
14H18O6SNa+: 337.0721, Found:
ꢀ 7 ≤ h ≤ 7, ꢀ 10 ≤ k ≤ 8, ꢀ 32 ≤ l ≤ 39
14332
337.0711; FTIR νmax/cmꢀ 1 3235 (br, O–H stretch), 1726 (C O stretch)
–
–
Reflections collected
Independent reflections
Data/restraints/parameters
Goodness-of-fit on F2
cmꢀ 1; Melting Point = 139–142 ◦C. [
α] = ꢀ 91.7 (MeOH).
D
3034 [Rint = 0.0353, Rsigma = 0.0243]
3034/0/193
1.031
4.6. Single crystal diffraction
Final R indexes [I ≥ 2
σ
(I)]
R1 = 0.0241, wR2 = 0.0623
R1 = 0.0246, wR2 = 0.0626
0.20/-0.20
Final R indexes [all data]
Largest diff. peak/hole/e Åꢀ 3
Flack parameter
Data for 5 were collected a Rigaku Fr-X DW diffractometer using
CuK at a temperature of 100K, cooled using an Oxford Cryostream 700.
Data for 6 were collected a Rigaku Fr-X DW diffractometer using MoK
ꢀ 0.007(7)
α
α
at a temperature of 150K, cooled using an Oxford Cryostream 700. The
data were collected and reduced using Rigaku CrysAlisPro [23] and the
structures solved and refined using the Shelx suite of programs (ShelXT
and ShelXL, respectively) [24] implemented through Olex2 [25] (see
Tables 1–3).
Table 3
Selected distances/Å and angles/◦ 5.
Na(1)–O(6)
2.287(4)
Na(1)–O(1)
2.345(4)
2.251(4)
2.330(4)
2.339(3)
5.742(3)
67.43(12)
81.37(13)
Na(2)–O(6)
Na(2)–O(4)
Declaration of competing interest
Na(3)–O(3)
Na(2)–Na(3)
O(1)-Na(1)-O(6)
O(6)-Na(2)-O(4)
The authors declare that they have no known competing financial
interests or personal relationships that could have appeared to influence
the work reported in this paper.
5