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The natural compound (1S,4S,5S,6R,7R,8R,9R,10S)-6-acet­oxy-4,9,10-trihy­droxy-2,2,5a,9-tetra­methyl­octa­hydro-2H-3,9a-methano­benzo[b]oxepin-5-yl furan-3-car­boxyl­ate, C22H30O9, (I), is a β-agaro­furan sesquiterpene isolated from the seeds of Maytenus boaria as part of a study of the secondary metabolites from Chilean flora. The compound presents a central structure formed by a deca­lin system esterified with acetate at site 1 and furan-3-carboxyl­ate at site 9. The chirality of the skeleton can be described as 1S,4S,5S,6R,7R,8R,9R,10S, which is consistent with that suggested by NMR studies. Unlike previously reported structures of sesquiterpenes containing a pure di­hydro-β-agaro­furan skeleton, (I) exhibits a three-dimensional hydrogen-bonded network.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S2053229617006817/fn3234sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S2053229617006817/fn3234Isup4.hkl
Contains datablock I

pdf

Portable Document Format (PDF) file https://doi.org/10.1107/S2053229617006817/fn3234sup3.pdf
NMR spectra of (I)

CCDC reference: 1548206

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015) and PLATON (Spek, 2009).

(1S,4S,5S,6R,7R,8R,9R,10S)-6-Acetoxy-4,9,10-trihydroxy-2,2,5a,9-tetramethyloctahydro-2H-3,9a-methanobenzo[b]oxepin-5-yl furan-3-carboxylate top
Crystal data top
C22H30O9Dx = 1.366 Mg m3
Mr = 438.46Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, P212121Cell parameters from 5831 reflections
a = 9.1605 (3) Åθ = 4.1–71.9°
b = 13.8069 (5) ŵ = 0.89 mm1
c = 16.8625 (7) ÅT = 295 K
V = 2132.74 (14) Å3Prisms, colourless
Z = 40.40 × 0.20 × 0.20 mm
F(000) = 936
Data collection top
Oxford Diffraction Gemini CCD S Ultra
diffractometer
3781 reflections with I > 2σ(I)
ω scans, thick slicesRint = 0.087
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
θmax = 71.9°, θmin = 4.1°
Tmin = 0.78, Tmax = 0.83h = 911
17785 measured reflectionsk = 1617
4153 independent reflectionsl = 2020
Refinement top
Refinement on F2Hydrogen site location: mixed
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.061 w = 1/[σ2(Fo2) + (0.1311P)2]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.165(Δ/σ)max < 0.001
S = 1.03Δρmax = 0.28 e Å3
4153 reflectionsΔρmin = 0.30 e Å3
295 parametersAbsolute structure: Flack x determined using 1547 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
3 restraintsAbsolute structure parameter: 0.18 (15)
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.0991 (2)0.28072 (15)0.15650 (13)0.0392 (5)
O20.1561 (3)0.09415 (17)0.17624 (18)0.0538 (6)
H20.090 (4)0.117 (3)0.146 (2)0.065*
O30.2575 (4)0.4631 (2)0.33803 (15)0.0640 (7)
H30.210 (5)0.489 (4)0.376 (2)0.077*
O1A0.1462 (4)0.1811 (2)0.32412 (18)0.0645 (7)
H1A0.139 (7)0.135 (3)0.291 (3)0.077*
O1B0.2037 (2)0.48421 (15)0.13053 (13)0.0408 (5)
O2B0.3398 (3)0.62082 (17)0.13775 (17)0.0560 (6)
O3B0.0276 (4)0.6172 (3)0.0462 (2)0.0771 (12)0.83 (2)
C4B'0.0276 (4)0.6172 (3)0.0462 (2)0.0771 (12)0.17 (2)
H4B'0.10630.59970.07810.093*0.17 (2)
O1C0.4858 (3)0.41320 (16)0.07259 (15)0.0484 (6)
O2C0.4060 (4)0.4272 (3)0.05184 (18)0.0739 (9)
C10.3791 (3)0.3366 (2)0.08843 (18)0.0389 (6)
H10.28950.35050.05880.047*
C20.4377 (4)0.2392 (2)0.0626 (2)0.0491 (7)
H2A0.52630.22410.09150.059*
H2B0.46040.24040.00640.059*
C30.3216 (4)0.1626 (2)0.0793 (2)0.0497 (8)
H3C0.35740.09990.06220.060*
H3D0.23470.17740.04870.060*
C40.2810 (3)0.1571 (2)0.1676 (2)0.0426 (7)
C50.2342 (3)0.2595 (2)0.19809 (17)0.0355 (6)
C60.1984 (4)0.2669 (2)0.2867 (2)0.0458 (7)
H60.28460.29040.31530.055*
C70.0840 (4)0.3485 (3)0.2825 (2)0.0488 (7)
H70.02580.35140.33120.059*
C80.1700 (4)0.4435 (3)0.2697 (2)0.0478 (7)
H80.10050.49670.26240.057*
C90.2780 (3)0.4425 (2)0.19852 (18)0.0385 (6)
H90.35870.48600.21210.046*
C100.3460 (3)0.34241 (19)0.17802 (17)0.0346 (6)
C110.0103 (3)0.3193 (2)0.2112 (2)0.0472 (7)
C120.1211 (4)0.2400 (3)0.2310 (3)0.0670 (11)
H12A0.16010.21360.18280.100*
H12B0.19900.26710.26210.100*
H12C0.07390.18960.26070.100*
C130.0947 (4)0.4001 (3)0.1708 (3)0.0580 (9)
H13A0.02770.44820.15170.087*
H13B0.16070.42910.20810.087*
H13C0.14900.37400.12710.087*
C140.4011 (4)0.1066 (3)0.2149 (3)0.0602 (10)
H14A0.38300.11480.27060.090*
H14B0.49390.13450.20160.090*
H14C0.40170.03890.20220.090*
C150.4883 (3)0.3359 (2)0.2259 (2)0.0453 (7)
H15A0.52180.27000.22670.068*
H15B0.47090.35730.27930.068*
H15C0.56120.37620.20180.068*
C1B0.2426 (3)0.5752 (2)0.10788 (18)0.0388 (6)
C2B0.1491 (4)0.6089 (2)0.04364 (19)0.0419 (6)
C3B0.0408 (5)0.5613 (3)0.0076 (3)0.0688 (11)
H3B0.01580.49740.01830.083*
C4B0.0417 (5)0.7046 (3)0.0446 (2)0.0652 (12)0.83 (2)
H4B0.01730.75760.07590.078*0.83 (2)
O3B'0.0417 (5)0.7046 (3)0.0446 (2)0.0652 (12)0.17 (2)
C5B0.1493 (5)0.7029 (3)0.0085 (3)0.0591 (9)
H5B0.21270.75350.02040.071*
C1C0.4837 (4)0.4543 (3)0.0021 (2)0.0533 (8)
C2C0.5879 (6)0.5372 (3)0.0036 (3)0.0787 (14)
H2CA0.64190.53260.05230.118*
H2CB0.65420.53530.04040.118*
H2CC0.53460.59710.00270.118*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0248 (9)0.0422 (10)0.0505 (11)0.0010 (8)0.0022 (8)0.0009 (8)
O20.0454 (13)0.0396 (11)0.0762 (16)0.0092 (10)0.0052 (12)0.0096 (11)
O30.0690 (17)0.0729 (16)0.0502 (14)0.0021 (14)0.0003 (13)0.0198 (12)
O1A0.0740 (18)0.0571 (15)0.0625 (15)0.0053 (13)0.0129 (15)0.0209 (12)
O1B0.0363 (10)0.0333 (9)0.0529 (11)0.0017 (7)0.0077 (9)0.0044 (8)
O2B0.0496 (13)0.0430 (12)0.0754 (16)0.0118 (10)0.0124 (12)0.0046 (11)
O3B0.072 (2)0.086 (2)0.073 (2)0.0075 (18)0.0261 (17)0.0179 (17)
C4B'0.072 (2)0.086 (2)0.073 (2)0.0075 (18)0.0261 (17)0.0179 (17)
O1C0.0415 (12)0.0480 (12)0.0558 (13)0.0083 (10)0.0079 (10)0.0055 (10)
O2C0.077 (2)0.085 (2)0.0600 (16)0.0002 (17)0.0053 (15)0.0227 (15)
C10.0336 (14)0.0389 (14)0.0443 (15)0.0018 (11)0.0041 (11)0.0026 (11)
C20.0445 (16)0.0458 (16)0.0571 (18)0.0020 (13)0.0101 (14)0.0044 (14)
C30.0483 (18)0.0406 (15)0.0602 (19)0.0021 (13)0.0023 (15)0.0086 (14)
C40.0353 (14)0.0322 (12)0.0602 (18)0.0005 (11)0.0034 (13)0.0033 (12)
C50.0290 (12)0.0330 (13)0.0447 (14)0.0009 (10)0.0023 (10)0.0036 (10)
C60.0454 (16)0.0452 (16)0.0466 (16)0.0004 (13)0.0033 (13)0.0079 (12)
C70.0429 (16)0.0543 (17)0.0494 (16)0.0030 (15)0.0112 (13)0.0008 (14)
C80.0462 (16)0.0480 (16)0.0490 (16)0.0029 (14)0.0075 (13)0.0085 (13)
C90.0353 (14)0.0362 (13)0.0440 (15)0.0011 (11)0.0028 (11)0.0007 (11)
C100.0274 (12)0.0340 (12)0.0426 (13)0.0018 (10)0.0017 (11)0.0020 (10)
C110.0277 (13)0.0498 (17)0.064 (2)0.0011 (12)0.0080 (13)0.0021 (14)
C120.0377 (17)0.066 (2)0.097 (3)0.0071 (16)0.0127 (19)0.012 (2)
C130.0305 (15)0.0557 (18)0.088 (3)0.0086 (13)0.0011 (16)0.0020 (18)
C140.052 (2)0.0444 (17)0.085 (3)0.0089 (16)0.0139 (19)0.0130 (17)
C150.0337 (14)0.0467 (16)0.0556 (17)0.0020 (12)0.0092 (13)0.0030 (13)
C1B0.0340 (14)0.0345 (13)0.0479 (15)0.0018 (11)0.0040 (12)0.0011 (10)
C2B0.0393 (15)0.0390 (14)0.0475 (15)0.0069 (12)0.0007 (12)0.0025 (11)
C3B0.073 (3)0.061 (2)0.073 (3)0.017 (2)0.024 (2)0.0168 (19)
C4B0.071 (2)0.061 (2)0.064 (2)0.0169 (18)0.0047 (18)0.0123 (16)
O3B'0.071 (2)0.061 (2)0.064 (2)0.0169 (18)0.0047 (18)0.0123 (16)
C5B0.060 (2)0.0451 (18)0.072 (2)0.0044 (16)0.0056 (19)0.0109 (16)
C1C0.056 (2)0.0459 (17)0.058 (2)0.0070 (15)0.0199 (17)0.0048 (15)
C2C0.096 (4)0.051 (2)0.089 (3)0.011 (2)0.037 (3)0.008 (2)
Geometric parameters (Å, º) top
O1—C51.453 (3)C7—C111.534 (5)
O1—C111.463 (4)C7—C81.544 (5)
O2—C41.445 (4)C7—H70.9800
O2—H20.854 (14)C8—C91.555 (4)
O3—C81.430 (4)C8—H80.9800
O3—H30.848 (14)C9—C101.555 (4)
O1A—C61.424 (4)C9—H90.9800
O1A—H1A0.851 (14)C10—C151.536 (4)
O1B—C1B1.360 (4)C11—C131.518 (5)
O1B—C91.452 (4)C11—C121.530 (5)
O2B—C1B1.201 (4)C12—H12A0.9600
O3B—C3B1.346 (5)C12—H12B0.9600
O3B—C4B1.364 (6)C12—H12C0.9600
C4B'—C3B1.346 (5)C13—H13A0.9600
C4B'—O3B'1.364 (6)C13—H13B0.9600
C4B'—H4B'0.9300C13—H13C0.9600
O1C—C1C1.318 (5)C14—H14A0.9600
O1C—C11.465 (3)C14—H14B0.9600
O2C—C1C1.214 (6)C14—H14C0.9600
C1—C21.512 (4)C15—H15A0.9600
C1—C101.543 (4)C15—H15B0.9600
C1—H10.9800C15—H15C0.9600
C2—C31.526 (5)C1B—C2B1.458 (4)
C2—H2A0.9700C2B—C3B1.336 (5)
C2—H2B0.9700C2B—C5B1.427 (5)
C3—C41.535 (5)C3B—H3B0.9300
C3—H3C0.9700C4B—C5B1.331 (6)
C3—H3D0.9700C4B—H4B0.9300
C4—C141.527 (5)O3B'—C5B1.331 (6)
C4—C51.564 (4)C5B—H5B0.9300
C5—C61.534 (4)C1C—C2C1.493 (6)
C5—C101.573 (4)C2C—H2CA0.9600
C6—C71.541 (5)C2C—H2CB0.9600
C6—H60.9800C2C—H2CC0.9600
C5—O1—C11110.7 (2)C15—C10—C1110.2 (2)
C4—O2—H2107 (3)C15—C10—C9106.0 (2)
C8—O3—H3113 (4)C1—C10—C9110.0 (2)
C6—O1A—H1A111 (4)C15—C10—C5113.4 (2)
C1B—O1B—C9117.7 (2)C1—C10—C5107.5 (2)
C3B—O3B—C4B106.0 (3)C9—C10—C5109.8 (2)
C3B—C4B'—O3B'106.0 (3)O1—C11—C13109.5 (3)
C3B—C4B'—H4B'127.0O1—C11—C12109.4 (3)
O3B'—C4B'—H4B'127.0C13—C11—C12106.6 (3)
C1C—O1C—C1117.8 (3)O1—C11—C7101.8 (2)
O1C—C1—C2110.7 (2)C13—C11—C7116.4 (3)
O1C—C1—C10105.8 (2)C12—C11—C7113.0 (3)
C2—C1—C10113.5 (2)C11—C12—H12A109.5
O1C—C1—H1108.9C11—C12—H12B109.5
C2—C1—H1108.9H12A—C12—H12B109.5
C10—C1—H1108.9C11—C12—H12C109.5
C1—C2—C3108.4 (3)H12A—C12—H12C109.5
C1—C2—H2A110.0H12B—C12—H12C109.5
C3—C2—H2A110.0C11—C13—H13A109.5
C1—C2—H2B110.0C11—C13—H13B109.5
C3—C2—H2B110.0H13A—C13—H13B109.5
H2A—C2—H2B108.4C11—C13—H13C109.5
C2—C3—C4112.4 (3)H13A—C13—H13C109.5
C2—C3—H3C109.1H13B—C13—H13C109.5
C4—C3—H3C109.1C4—C14—H14A109.5
C2—C3—H3D109.1C4—C14—H14B109.5
C4—C3—H3D109.1H14A—C14—H14B109.5
H3C—C3—H3D107.8C4—C14—H14C109.5
O2—C4—C14104.0 (3)H14A—C14—H14C109.5
O2—C4—C3108.6 (3)H14B—C14—H14C109.5
C14—C4—C3110.8 (3)C10—C15—H15A109.5
O2—C4—C5107.1 (2)C10—C15—H15B109.5
C14—C4—C5116.0 (3)H15A—C15—H15B109.5
C3—C4—C5109.9 (2)C10—C15—H15C109.5
O1—C5—C6105.9 (2)H15A—C15—H15C109.5
O1—C5—C4104.9 (2)H15B—C15—H15C109.5
C6—C5—C4116.1 (2)O2B—C1B—O1B124.1 (3)
O1—C5—C10107.7 (2)O2B—C1B—C2B125.4 (3)
C6—C5—C10107.5 (2)O1B—C1B—C2B110.5 (3)
C4—C5—C10114.1 (2)C3B—C2B—C5B105.0 (3)
O1A—C6—C5116.6 (3)C3B—C2B—C1B128.2 (3)
O1A—C6—C7113.6 (3)C5B—C2B—C1B126.8 (3)
C5—C6—C798.6 (2)C2B—C3B—O3B111.8 (4)
O1A—C6—H6109.2C2B—C3B—C4B'111.8 (4)
C5—C6—H6109.2C2B—C3B—H3B124.1
C7—C6—H6109.2O3B—C3B—H3B124.1
C11—C7—C6103.1 (3)C5B—C4B—O3B110.1 (3)
C11—C7—C8113.6 (3)C5B—C4B—H4B125.0
C6—C7—C8106.3 (3)O3B—C4B—H4B125.0
C11—C7—H7111.1C5B—O3B'—C4B'110.1 (3)
C6—C7—H7111.1O3B'—C5B—C2B107.1 (4)
C8—C7—H7111.1C4B—C5B—C2B107.1 (4)
O3—C8—C7109.5 (3)C4B—C5B—H5B126.4
O3—C8—C9105.5 (3)C2B—C5B—H5B126.4
C7—C8—C9115.1 (3)O2C—C1C—O1C123.5 (4)
O3—C8—H8108.8O2C—C1C—C2C124.3 (4)
C7—C8—H8108.8O1C—C1C—C2C112.3 (4)
C9—C8—H8108.8C1C—C2C—H2CA109.5
O1B—C9—C10111.4 (2)C1C—C2C—H2CB109.5
O1B—C9—C8107.9 (2)H2CA—C2C—H2CB109.5
C10—C9—C8115.7 (3)C1C—C2C—H2CC109.5
O1B—C9—H9107.1H2CA—C2C—H2CC109.5
C10—C9—H9107.1H2CB—C2C—H2CC109.5
C8—C9—H9107.1
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O2Ci0.85 (1)2.39 (3)3.120 (4)144 (4)
O3—H3···O2Cii0.85 (1)1.99 (2)2.826 (4)168 (5)
O1A—H1A···O20.85 (1)2.02 (3)2.769 (4)146 (5)
C12—H12C···O1A0.962.293.020 (6)133
C13—H13A···O1B0.962.213.047 (4)146
C14—H14A···O1A0.962.523.147 (6)123
C4B—H4B···O2Biii0.932.563.421 (4)154
Symmetry codes: (i) x1/2, y+1/2, z; (ii) x+1/2, y+1, z+1/2; (iii) x1/2, y+3/2, z.
The 16 [15?] reported structures with the same dihydro-β-agarofuran skeleton as in (I). top
NumberCSD refcodeaReferenceChemical name
1ALEWOFMbaning et al. (2016)5-Acetoxy-2-hydroxy-2,6,10,10-tetramethyl-4-oxo-11-oxatricyclo[7.2.1.01,6]dodecane-7,12-diyl dibenzoate
2ALEXOGMbaning et al. (2016)4,5,8-Triacetoxy-2-hydroxy-2,6,10,10-tetramethyl-11-oxatricyclo[7.2.1.01,6]dodecane-7,12-diyl dibenzoate hexane solvate
3ALEYOHMbaning et al. (2016)4-Acetoxy-5,12-bis(benzoyloxy)-2-hydroxy-2,6,10,10-tetramethyl-11-oxatricyclo[7.2.1.01,6]dodec-7-yl nicotinate
4CELBRBSmith et al. (1976)Celorbicol mono-p-bromobenzoate
5EJACOIYeboah et al. (2010)2,6,10,10-Tetramethyl-4-oxo-11-oxatricyclo[7.2.1.01,6]dodecane-5,7-diyl bis(furan-3-carboxylate)
6EJACOI01Yeboah et al. (2010)2,6,10,10-Tetramethyl-4-oxo-11-oxatricyclo[7.2.1.01,6]dodecane-5,7-diyl bis(furan-3-carboxylate)
7ISOCELSmith et al. (1976)Isocelorbicol
8JAGREOHori et al. (1987)Regelidine
9KUXGEPYongqiang et al. (1990)1b,2b-Diacetoxy-9a-(3-phenyl-2-oxiranylcarboxy)-β-dihydroagarofuran
10KUXGEP10Wang & Tu (1995)1b,2b-Diacetoxy-9a-(3-phenyl-2-oxiranylcarboxy)-β-dihydroagarofuran
11OSOVUOTorres-Romero et al. (2011)2,6,10,10-Tetramethyl-11-oxatricyclo[7.2.1.01,6]dodecane-2,5,7,8,12-pentol hemihydrate
12SIFNEABegley et al. (1990)6-O-Acetyl-9-O-[(E)-cinnamoyl]-1-O-glycoloyl-1,4,6,9-tetrahydroxydihydroagarofuran
13UKUBILMehta & Kumaran (2003)7-Benzoyloxy-2,6,10,10-tetramethyl-11-oxatricyclo[7.2.1.01,6]dodecane-3,4,12-triol
14UKUBIL01Kumaran & Mehta (2015)7-Benzoyloxy-2,6,10,10-tetramethyl-11-oxatricyclo[7.2.1.01,6]dodecane-3,4,12-triol
15YABZACGonzalez et al. (1992)(3S,4R,5R,7R,10R)-3,4-Dihydroxydihydro-β-agarofuran
Reference: Groom et al. (2016).
Hydrogen-bond geometry (Å, °) for (I) top
CodeD—H···AD—HH···AD···AD—H···A
#1O1A—H1A···O20.851 (14)2.02 (3)2.769 (4)146 (5)
#2C12—H12C···O1A0.962.293.020 (6)133
#3C14—H14A···O1A0.962.523.147 (6)123
#4C13—H13A···O1B0.962.213.047 (4)146
#5O3—H3···O2Ci0.848 (14)1.992 (18)2.826 (4)168 (5)
#6O2—H2···O2Cii0.854 (14)2.39 (3)3.120 (4)144 (4)
Symmetry codes: (i) -x+1/2, -y+1, z+1/2; (ii) x-1/2, -y+1/2, -z.
1H (600 MHz) and 13C (150 MHz) NMR data of MB 22 in DMSO-d6. Chemical shifts (δ) in ppm and coupling constants (J) in Hz. COSY is correlation spectroscopy and HMBC is heteronuclear multiple-bond correlation spectroscopy. top
Position1H13CCOSYHMBC
15.07 (dd, J = 8.2, 5.2)72.52 a,b9, 10, 15, 1C
21.68 (m) 1.45 (overlap)22.93 a,b
31.37 (m) 1.80 (td, J = 16.2, 4.5)35.42 a,b4, 7
482.1
591.4
64.78 (s)73.774, 8
72.10 (d, J = 3.8)57.46, 84, 5, 8, 9, 13
83.98 (t, J = 4.3)72.977, 9, 10
94.77 (d, J = 7.6)79.15, 7, 8, 15, 1B
1049.5
1171.8
121.46 (overlap)26.1
131.46 (overlap)30.2
141.38 (s)25.7
151.32 (s)19.81, 5, 9, 10
1B161.1
2B118.5
3B8.16 (dd, J = 1.8, 0.9)148.44B
4B7.78 (t, J = 2.2)144.83B, 5B
5B6.66 (dd, J = 2.2, 0.9)109.44B
1C169.42C
2C1.63 (s)20.71C
 

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