organic compounds
(1R,3R,4R,6S)-4-(7-Methoxy-2-oxo-2H-chromen-6-yl)-1-methyl-3,6-dioxabicyclo[3.1.0]hexan-2-yl acetate
aNatural Products Research Laboratory, School of Science, Mae Fah Luang, University, Tasud, Muang, Chiang Rai 57100, Thailand, bDepartment of Chemistry, University of Hull, Cottingham Road, Hull HU6 7RX, England, and cDepartment of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
*Correspondence e-mail: apinpus@gmail.com
In the title compound, C17H16O7, which was isolated from the leaves of Micromelum integerrimum, the furan ring adopts an with the O atom as the flap. An intramolecular C—H⋯O hydrogen bond occurs. The carbonyl O atom is disordered in a 0.57 (8):0.43 (8) ratio. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds into a C(10) chain along [010].
Related literature
Micromelum integerrimum is a shrub in the Rutacae family containing the coumarin molecule, micromelin, as the major chemical constituent (Cassady et al., 1979). Many including micromelin have been extracted from Rutacae plants, and for some their cytotoxicity has been investigated (Sripisut et al., 2012; He et al., 2001). For previous reports on the isolation of micromelin (micromelumin) from a Northern Queensland collection, an Assamese collection, and a Northeast Thailand collection, see: Lamberton et al. (1967); Das et al. (1984); Siridechakorn et al. (2012). For detailed H1 NMR spectroscopic data, see: Das et al. (1984); Siridechakorn et al. (2012). For a phytochemical investigation, see: Siridechakorn et al. (2012). For a closely related micromelin structure, C15H12O6, see: Fun et al. (2011). For hydrogen-bond motifs, see: Bernstein et al. (1995). For puckering parameters, see: Cremer & Pople (1975).
Experimental
Crystal data
|
Refinement
|
Data collection: APEX2 (Bruker, 2008); cell SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2007); software used to prepare material for publication: publCIF (Westrip, 2010) and PLATON (Spek, 2009).
Supporting information
10.1107/S1600536812047617/bx2427sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812047617/bx2427Isup2.hkl
The title compound was obtained from an acetone extract of Micromelum integerrimum leaves (0.55 kg), which are collected from Chiang Rai Province, Thailand. From seven fractions (A—G) yielded by
using hexanes-acetone, the title compound (295.9 mg) was isolated from fraction D by also using 2% acetone-CH2Cl2. The crystals were then crystallized by slowly evaporation of the solvent.The carbonyl group O atom is disordered over two sets of sites in a 0.57 (8):0.43 (8) ratio.Friedel opposites were merged in the final cycles of
as there is no appreciable at the wavelength used for data collection. H atoms were placed in geometrically idealized positions (C—H= 0.91-1.06 Å, C(methyl)—H=0.96Å and were constrained to ride on their parects atoms with Uiso(H)= 1.2Ueq(C) and 1.5Ueq(C) respectively , except H3, H4, H5, and H8, were refined freely, with isotropic displacement parameters.Data collection: APEX2 (Bruker, 2008); cell
SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2007); software used to prepare material for publication: publCIF (Westrip, 2010) and PLATON (Spek, 2009).C17H16O7 | F(000) = 348 |
Mr = 332.31 | Dx = 1.388 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 3003 reflections |
a = 10.4825 (16) Å | θ = 1.9–28.3° |
b = 6.9213 (9) Å | µ = 0.11 mm−1 |
c = 11.0212 (18) Å | T = 298 K |
β = 95.970 (7)° | Block, colourless |
V = 795.3 (2) Å3 | 0.64 × 0.32 × 0.24 mm |
Z = 2 |
Bruker SMART APEXII CCD area-detector diffractometer | 2123 independent reflections |
Radiation source: fine-focus sealed tube | 1692 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.021 |
ω scans | θmax = 28.3°, θmin = 2.6° |
Absorption correction: multi-scan (SADABS; Bruker, 1997) | h = −13→8 |
Tmin = 0.653, Tmax = 0.746 | k = −7→9 |
4381 measured reflections | l = −14→14 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.046 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.136 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0701P)2 + 0.1456P] where P = (Fo2 + 2Fc2)/3 |
2123 reflections | (Δ/σ)max < 0.001 |
223 parameters | Δρmax = 0.47 e Å−3 |
2 restraints | Δρmin = −0.24 e Å−3 |
C17H16O7 | V = 795.3 (2) Å3 |
Mr = 332.31 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 10.4825 (16) Å | µ = 0.11 mm−1 |
b = 6.9213 (9) Å | T = 298 K |
c = 11.0212 (18) Å | 0.64 × 0.32 × 0.24 mm |
β = 95.970 (7)° |
Bruker SMART APEXII CCD area-detector diffractometer | 2123 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1997) | 1692 reflections with I > 2σ(I) |
Tmin = 0.653, Tmax = 0.746 | Rint = 0.021 |
4381 measured reflections |
R[F2 > 2σ(F2)] = 0.046 | 2 restraints |
wR(F2) = 0.136 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.47 e Å−3 |
2123 reflections | Δρmin = −0.24 e Å−3 |
223 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
O1 | −0.09274 (16) | 0.0334 (4) | 0.56547 (17) | 0.0485 (5) | |
C2 | −0.2211 (2) | 0.0363 (5) | 0.5224 (3) | 0.0509 (6) | |
O2 | −0.2958 (2) | 0.0392 (4) | 0.5982 (2) | 0.0701 (7) | |
C3 | −0.2509 (2) | 0.0355 (5) | 0.3921 (3) | 0.0542 (7) | |
H3 | −0.335 (3) | 0.0402 (6) | 0.3602 (13) | 0.065* | |
C4 | −0.1595 (2) | 0.0280 (5) | 0.3155 (3) | 0.0490 (6) | |
H4 | −0.1858 (8) | 0.0256 (5) | 0.219 (3) | 0.059* | |
C5 | 0.0765 (2) | 0.0093 (4) | 0.2907 (2) | 0.0434 (6) | |
H5 | 0.0579 (6) | 0.0024 (5) | 0.199 (3) | 0.052* | |
C6 | 0.2015 (2) | 0.0050 (4) | 0.3416 (2) | 0.0438 (6) | |
C7 | 0.2260 (2) | 0.0189 (4) | 0.4699 (2) | 0.0425 (5) | |
O3 | 0.35235 (16) | 0.0218 (4) | 0.51324 (18) | 0.0587 (6) | |
C16 | 0.3858 (3) | 0.0418 (6) | 0.6410 (3) | 0.0572 (7) | |
H16A | 0.3431 | 0.1526 | 0.6702 | 0.086* | |
H16B | 0.4769 | 0.0582 | 0.6572 | 0.086* | |
H16C | 0.3600 | −0.0719 | 0.6820 | 0.086* | |
C8 | 0.1272 (2) | 0.0280 (5) | 0.5436 (2) | 0.0423 (5) | |
H8 | 0.1452 (6) | 0.0344 (5) | 0.633 (3) | 0.051* | |
C9 | 0.0026 (2) | 0.0280 (4) | 0.4886 (2) | 0.0389 (5) | |
C10 | −0.0266 (2) | 0.0232 (4) | 0.3624 (2) | 0.0408 (5) | |
C11 | 0.3156 (3) | −0.0214 (5) | 0.2692 (3) | 0.0502 (7) | |
H11 | 0.3788 | −0.1042 | 0.3159 | 0.060* | |
O11 | 0.2824 (2) | −0.1069 (4) | 0.1510 (2) | 0.0606 (6) | |
C12 | 0.3783 (3) | 0.1663 (6) | 0.2434 (3) | 0.0563 (8) | |
H12 | 0.3774 | 0.2751 | 0.3003 | 0.068* | |
O12 | 0.48617 (19) | 0.1365 (5) | 0.1725 (2) | 0.0697 (7) | |
C13 | 0.3647 (3) | 0.1984 (6) | 0.1116 (3) | 0.0621 (8) | |
C14 | 0.2937 (3) | 0.0253 (6) | 0.0571 (3) | 0.0599 (8) | |
H14 | 0.3396 | −0.0323 | −0.0070 | 0.072* | |
O13 | 0.1675 (2) | 0.0904 (4) | 0.00763 (19) | 0.0656 (7) | |
C15 | 0.3633 (4) | 0.3895 (9) | 0.0470 (4) | 0.0931 (14) | |
H15A | 0.2762 | 0.4289 | 0.0248 | 0.140* | |
H15B | 0.4066 | 0.3773 | −0.0252 | 0.140* | |
H15C | 0.4062 | 0.4845 | 0.1000 | 0.140* | |
C17 | 0.1085 (3) | −0.0092 (6) | −0.0852 (3) | 0.0652 (9) | |
C18 | −0.0245 (4) | 0.0466 (8) | −0.1189 (4) | 0.0793 (11) | |
H18A | −0.0547 | −0.0112 | −0.1957 | 0.119* | |
H18B | −0.0301 | 0.1847 | −0.1258 | 0.119* | |
H18C | −0.0762 | 0.0031 | −0.0573 | 0.119* | |
O19A | 0.1483 (6) | −0.1679 (10) | −0.1149 (6) | 0.0843 (12)* | 0.567 (8) |
O19B | 0.1763 (7) | −0.0896 (14) | −0.1535 (7) | 0.0843 (12)* | 0.433 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0370 (8) | 0.0543 (11) | 0.0556 (10) | 0.0019 (10) | 0.0112 (7) | 0.0022 (11) |
C2 | 0.0374 (12) | 0.0414 (14) | 0.0750 (18) | 0.0000 (13) | 0.0113 (12) | 0.0053 (16) |
O2 | 0.0463 (10) | 0.0742 (16) | 0.0943 (16) | −0.0031 (13) | 0.0283 (10) | 0.0057 (15) |
C3 | 0.0318 (11) | 0.0494 (15) | 0.0794 (19) | −0.0042 (14) | −0.0037 (11) | 0.0071 (17) |
C4 | 0.0404 (12) | 0.0459 (14) | 0.0585 (15) | −0.0051 (14) | −0.0054 (11) | 0.0033 (15) |
C5 | 0.0440 (12) | 0.0436 (14) | 0.0424 (12) | −0.0009 (12) | 0.0030 (10) | 0.0011 (12) |
C6 | 0.0382 (11) | 0.0446 (15) | 0.0489 (13) | 0.0013 (12) | 0.0067 (10) | −0.0025 (13) |
C7 | 0.0328 (10) | 0.0427 (13) | 0.0513 (13) | 0.0040 (12) | 0.0007 (9) | 0.0008 (13) |
O3 | 0.0323 (8) | 0.0833 (16) | 0.0599 (11) | 0.0021 (12) | 0.0015 (7) | −0.0034 (13) |
C16 | 0.0388 (12) | 0.0655 (19) | 0.0640 (16) | 0.0071 (15) | −0.0103 (11) | −0.0031 (17) |
C8 | 0.0380 (11) | 0.0451 (13) | 0.0433 (12) | 0.0010 (13) | 0.0016 (9) | −0.0007 (13) |
C9 | 0.0344 (10) | 0.0341 (11) | 0.0486 (12) | 0.0009 (12) | 0.0059 (9) | 0.0029 (12) |
C10 | 0.0354 (10) | 0.0373 (12) | 0.0491 (12) | −0.0022 (12) | 0.0006 (9) | 0.0003 (12) |
C11 | 0.0416 (13) | 0.0589 (18) | 0.0509 (14) | 0.0051 (13) | 0.0080 (11) | −0.0103 (13) |
O11 | 0.0620 (13) | 0.0600 (12) | 0.0615 (13) | 0.0007 (11) | 0.0147 (10) | −0.0160 (11) |
C12 | 0.0384 (13) | 0.075 (2) | 0.0578 (16) | −0.0085 (15) | 0.0171 (12) | −0.0156 (16) |
O12 | 0.0379 (10) | 0.110 (2) | 0.0636 (13) | −0.0054 (12) | 0.0170 (9) | −0.0161 (14) |
C13 | 0.0450 (15) | 0.082 (2) | 0.0624 (18) | −0.0085 (17) | 0.0210 (13) | −0.0089 (18) |
C14 | 0.0442 (13) | 0.083 (2) | 0.0541 (15) | 0.0060 (18) | 0.0143 (11) | −0.0172 (18) |
O13 | 0.0501 (11) | 0.0877 (18) | 0.0588 (12) | 0.0055 (11) | 0.0046 (9) | −0.0196 (12) |
C15 | 0.081 (3) | 0.104 (3) | 0.099 (3) | −0.023 (3) | 0.030 (2) | 0.021 (3) |
C17 | 0.0663 (18) | 0.083 (3) | 0.0468 (14) | 0.0084 (18) | 0.0062 (13) | −0.0103 (16) |
C18 | 0.071 (2) | 0.092 (3) | 0.072 (2) | −0.001 (2) | −0.0103 (17) | 0.006 (2) |
O1—C9 | 1.377 (3) | C11—O11 | 1.441 (3) |
O1—C2 | 1.380 (3) | C11—C12 | 1.496 (5) |
C2—O2 | 1.203 (3) | C11—H11 | 0.9800 |
C2—C3 | 1.438 (4) | O11—C14 | 1.396 (5) |
C3—C4 | 1.343 (4) | C12—O12 | 1.455 (3) |
C3—H3 | 0.9168 | C12—C13 | 1.463 (4) |
C4—C10 | 1.435 (3) | C12—H12 | 0.9800 |
C4—H4 | 1.0676 | O12—C13 | 1.441 (4) |
C5—C6 | 1.371 (3) | C13—C15 | 1.501 (7) |
C5—C10 | 1.406 (3) | C13—C14 | 1.502 (5) |
C5—H5 | 1.0053 | C14—O13 | 1.450 (4) |
C6—C7 | 1.413 (4) | C14—H14 | 0.9800 |
C6—C11 | 1.517 (3) | O13—C17 | 1.332 (4) |
C7—O3 | 1.361 (3) | C15—H15A | 0.9600 |
C7—C8 | 1.383 (3) | C15—H15B | 0.9600 |
O3—C16 | 1.422 (3) | C15—H15C | 0.9600 |
C16—H16A | 0.9600 | C17—O19B | 1.222 (7) |
C16—H16B | 0.9600 | C17—O19A | 1.231 (7) |
C16—H16C | 0.9600 | C17—C18 | 1.456 (5) |
C8—C9 | 1.382 (3) | C18—H18A | 0.9600 |
C8—H8 | 0.9857 | C18—H18B | 0.9600 |
C9—C10 | 1.393 (4) | C18—H18C | 0.9600 |
C9—O1—C2 | 122.2 (2) | C6—C11—H11 | 108.7 |
O2—C2—O1 | 116.3 (3) | C14—O11—C11 | 111.7 (3) |
O2—C2—C3 | 127.2 (3) | O12—C12—C13 | 59.20 (19) |
O1—C2—C3 | 116.5 (2) | O12—C12—C11 | 111.1 (3) |
C4—C3—C2 | 122.2 (2) | C13—C12—C11 | 108.8 (3) |
C4—C3—H3 | 118.9 | O12—C12—H12 | 120.8 |
C2—C3—H3 | 118.9 | C13—C12—H12 | 120.8 |
C3—C4—C10 | 120.3 (2) | C11—C12—H12 | 120.8 |
C3—C4—H4 | 119.9 | C13—O12—C12 | 60.65 (19) |
C10—C4—H4 | 119.9 | O12—C13—C12 | 60.14 (19) |
C6—C5—C10 | 121.9 (2) | O12—C13—C15 | 116.6 (3) |
C6—C5—H5 | 119.0 | C12—C13—C15 | 126.9 (4) |
C10—C5—H5 | 119.0 | O12—C13—C14 | 109.0 (3) |
C5—C6—C7 | 118.4 (2) | C12—C13—C14 | 105.6 (3) |
C5—C6—C11 | 124.1 (2) | C15—C13—C14 | 122.2 (3) |
C7—C6—C11 | 117.6 (2) | O11—C14—O13 | 109.8 (2) |
O3—C7—C8 | 123.6 (2) | O11—C14—C13 | 107.6 (3) |
O3—C7—C6 | 115.0 (2) | O13—C14—C13 | 107.3 (3) |
C8—C7—C6 | 121.4 (2) | O11—C14—H14 | 110.7 |
C7—O3—C16 | 118.7 (2) | O13—C14—H14 | 110.7 |
O3—C16—H16A | 109.5 | C13—C14—H14 | 110.7 |
O3—C16—H16B | 109.5 | C17—O13—C14 | 117.4 (3) |
H16A—C16—H16B | 109.5 | C13—C15—H15A | 109.5 |
O3—C16—H16C | 109.5 | C13—C15—H15B | 109.5 |
H16A—C16—H16C | 109.5 | H15A—C15—H15B | 109.5 |
H16B—C16—H16C | 109.5 | C13—C15—H15C | 109.5 |
C9—C8—C7 | 118.3 (2) | H15A—C15—H15C | 109.5 |
C9—C8—H8 | 120.9 | H15B—C15—H15C | 109.5 |
C7—C8—H8 | 120.9 | O19B—C17—O13 | 117.1 (4) |
O1—C9—C8 | 116.3 (2) | O19A—C17—O13 | 121.5 (4) |
O1—C9—C10 | 121.2 (2) | O19B—C17—C18 | 124.5 (4) |
C8—C9—C10 | 122.5 (2) | O19A—C17—C18 | 120.7 (4) |
C9—C10—C5 | 117.4 (2) | O13—C17—C18 | 114.4 (3) |
C9—C10—C4 | 117.6 (2) | C17—C18—H18A | 109.5 |
C5—C10—C4 | 125.0 (2) | C17—C18—H18B | 109.5 |
O11—C11—C12 | 104.7 (2) | H18A—C18—H18B | 109.5 |
O11—C11—C6 | 113.3 (2) | C17—C18—H18C | 109.5 |
C12—C11—C6 | 112.4 (2) | H18A—C18—H18C | 109.5 |
O11—C11—H11 | 108.7 | H18B—C18—H18C | 109.5 |
C12—C11—H11 | 108.7 |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···O19Ai | 1.07 (3) | 2.46 (2) | 3.064 (8) | 114 (1) |
C5—H5···O13 | 1.01 (3) | 2.58 (3) | 3.403 (3) | 139 (1) |
C12—H12···O2ii | 0.98 | 2.35 | 3.282 (5) | 158 |
C16—H16B···O2iii | 0.96 | 2.54 | 3.419 (4) | 153 |
Symmetry codes: (i) −x, y+1/2, −z; (ii) −x, y+1/2, −z+1; (iii) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C17H16O7 |
Mr | 332.31 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 298 |
a, b, c (Å) | 10.4825 (16), 6.9213 (9), 11.0212 (18) |
β (°) | 95.970 (7) |
V (Å3) | 795.3 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.64 × 0.32 × 0.24 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 1997) |
Tmin, Tmax | 0.653, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4381, 2123, 1692 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.666 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.046, 0.136, 1.06 |
No. of reflections | 2123 |
No. of parameters | 223 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.47, −0.24 |
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2007), publCIF (Westrip, 2010) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···O19Ai | 1.07 (3) | 2.463 (17) | 3.064 (8) | 114.4 (7) |
C5—H5···O13 | 1.01 (3) | 2.58 (3) | 3.403 (3) | 138.7 (6) |
C12—H12···O2ii | 0.98 | 2.35 | 3.282 (5) | 158 |
C16—H16B···O2iii | 0.96 | 2.54 | 3.419 (4) | 153 |
Symmetry codes: (i) −x, y+1/2, −z; (ii) −x, y+1/2, −z+1; (iii) x+1, y, z. |
Acknowledgements
The Thailand Research Fund is acknowledged for a research grant.
References
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Micromelum integerrimum is a shrub in the Rutacae family containing the coumarin molecule, micromilin, as the major chemical constituent (Cassady et al., 1979). Many coumarins including micromilin have been extracted from Rutacae plants, and for some their cytotoxicity has been investigated (Sripisut et al., 2012; He et al., 2001). In the attempt to investigate the chemical constitutents of the extract of Micromelum integerrimum leaves collected from Chiang Rai province in the Northern part of Thailand (March 2012), the colourless crystals of the title compound have been isolated and examined.
The absolute configurations of the four chiral centres in the molecule, (I) (C11, C12, C13, and C14) were assigned from a previous report (Das et al., 1984) as R, R, R and S, respectively. The benzene and dihydropyran ring system (C2–C10/O1) and also the carboxyl O2 and the methoxy O3 atoms are co-planar with the r.m.s. 0.004 (3) Å (Spek, 2009). A deviation of atoms O2 and O3 from the benzene and dihydropyran ring system are 0.028 (2) Å and 0.040 (2) Å, respectively. The five-membered furan ring (C11–C14/O11) shows envelope conformation with the puckering atom O11 of 0.075 (2) Å, and forms an angle of 66.11 (9)° to the twelve-membered benzene–dihydropyran due to free rotation about the C6—C11 bond. The puckering parameters Q and ϕ of the furan ring are 0.116 (2) Å and 176.4 (12)°, respectively (Cremer & Pople, 1975). The orientation of the oxiran ring (C12–C13/O12) attached to the furan can be defined by the dihedral angle being 79.5 (2)° with atom O12 of the oxirane ring located 1.250 (2) Å away from the furan plane. Regarding the acetate group, atom O19 shows minor positional disorder over two sites. The acetate O13 is arranged at 64.19 (15)° in reference to the furan plane, and the torsion angle measured on C14–O13–C17–C18 is 171.6 (2)°.In the crystal of (I), the molecules are linked by weak C—H···O hydrogen-bonding interactions into a chain along [010] with set-graph notation C(10), (Bernstein, et al., 1995)