organic compounds
[1R-(1α,2α,4α,5β,6α,7α)]-4-Benzoyloxymethyl-5,6-dihydroxy-3,8-dioxatricyclo[5.1.0.02,4]octan-5-yl acetate (3-deacetylcrotepoxide) from Kaempferia rotunda Val.
aDepartment of Chemistry, Universiti Teknologi Malaysia, 81310 Skudai, Malaysia, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
The title compound, C16H16O7, isolated from Kaempferia rotunda rhizomes, features a six-membered cyclohexane ring that adopts a twisted-boat conformation owing to the presence of two adjacent epoxide attachments that lock in four of the six axial positions. The CH3CO2– and HO– substituents occupy equatorial positions. However, the bond angles at the ring carbon connected to the C6H5CO2CH2– substituent deviate signifcantly from the idealized tetrahedral angles as the carbon atom is part of an epoxide ring. In the crystal, the molecules are linked into chains by O—H⋯O hydrogen bonds.
Related literature
For the isolation of the compound from Kaempferia rotunda, see: Pancharoen et al. (1996).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
https://doi.org/10.1107/S1600536810042686/bt5386sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810042686/bt5386Isup2.hkl
Kaempferia rotunda rhizomes were purchased from a market in Kempas, Johor. The rhizomes were dried and then grounded. The grounded rhizomes were extracted with n-hexane (4.5 L), ethyl acetate (4.5 L) and methanol (4.5 L) in a soxhlet extractor for 16 h. The extracts were concentrated to give a dark brown semi-solid from the n-hexane extract (2.32 g), a dark brown oil from the ethyl acetate extract (6.80 g) and a dark brown viscous liquid from the methanol extract (15.27 g). The ethyl acetate extract (6.80 g) was fractionated by VLC (260 g, column size: 10 x 12 cm) by using petroleum ether, ether and ethyl acetate to afford four fractions, (0.02 g, 0.15 g, 2.70 g and 2.50 g. Evaporation of the solvent of the third fraction yielded 3-deacetylcrotepoxide (0.145 g, 2.13%) as colorless crystals.
The
was assumed from that obtained from spectroscopic measurements (Pancharoen et al., 1996).Carbon-bound H-atoms were placed in calculated positions (C—H 0.95–0.99 Å) and were included in the
in the riding model approximation, with U(H) set to 1.2–15U(C).The hydroxy H-atom was located in a difference Fourier map, and was refined isotropically with the O–H distance restrained to 0.84±0.01 Å.
1374 Friedel pairs were merged.
Kaempferia rotunda is one of the four Malaysian Kaempferia of the Zingiberaceae family; among the constitutents isolated is 3-deacetylcrotepoxide (Scheme I), which was first reported by Pancharoen et al. (1996). 3-Deacetylcrotepoxide (Scheme I) features a six-membered cyclohexane ring that adopts a twisted boat conformation owing to the presence of two adjacent epoxide attachements that tie up four of the six axial positions. The CH3CO2– and HO– substituents occupy regular equatorial positions as each is connected to a methine carbon atom (Fig. 1). However, the bond angles at the ring carbon connected to the C6H5CO2CH2– substituent deviate signifcantly from the idealized tetrahedral angles as the carbon atom is part of an epoxide ring [112.4 (2), 117.9 (2), 120.3 (3) °].
For the isolation of the compound from Kaempferia rotunda, see: Pancharoen et al. (1996).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).Fig. 1. Anisotropic displacement ellipsoid plot (Barbour, 2001) of C16H16O7 at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius. |
C16H16O7 | F(000) = 672 |
Mr = 320.29 | Dx = 1.445 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 1788 reflections |
a = 5.7451 (7) Å | θ = 3.1–20.0° |
b = 7.1746 (9) Å | µ = 0.12 mm−1 |
c = 35.708 (5) Å | T = 100 K |
V = 1471.9 (3) Å3 | Prism, colorless |
Z = 4 | 0.35 × 0.05 × 0.05 mm |
Bruker SMART APEX diffractometer | 1730 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.073 |
Graphite monochromator | θmax = 27.5°, θmin = 1.1° |
ω scans | h = −7→7 |
14228 measured reflections | k = −9→9 |
2011 independent reflections | l = −46→46 |
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)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.117 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.12 | w = 1/[σ2(Fo2) + (0.0674P)2] where P = (Fo2 + 2Fc2)/3 |
2011 reflections | (Δ/σ)max = 0.001 |
213 parameters | Δρmax = 0.37 e Å−3 |
1 restraint | Δρmin = −0.33 e Å−3 |
C16H16O7 | V = 1471.9 (3) Å3 |
Mr = 320.29 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 5.7451 (7) Å | µ = 0.12 mm−1 |
b = 7.1746 (9) Å | T = 100 K |
c = 35.708 (5) Å | 0.35 × 0.05 × 0.05 mm |
Bruker SMART APEX diffractometer | 1730 reflections with I > 2σ(I) |
14228 measured reflections | Rint = 0.073 |
2011 independent reflections |
R[F2 > 2σ(F2)] = 0.038 | 1 restraint |
wR(F2) = 0.117 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.12 | Δρmax = 0.37 e Å−3 |
2011 reflections | Δρmin = −0.33 e Å−3 |
213 parameters |
x | y | z | Uiso*/Ueq | ||
O1 | 0.4671 (3) | 0.4022 (3) | 0.89359 (5) | 0.0161 (4) | |
O2 | 0.1026 (4) | 0.3085 (3) | 0.88101 (5) | 0.0237 (5) | |
O3 | 0.5062 (3) | 0.3882 (3) | 0.78913 (5) | 0.0166 (4) | |
O4 | 0.1819 (4) | 0.5944 (3) | 0.74537 (5) | 0.0204 (5) | |
O5 | 0.4387 (4) | 0.9627 (3) | 0.80058 (6) | 0.0220 (5) | |
H5 | 0.541 (5) | 0.999 (5) | 0.7854 (8) | 0.032 (10)* | |
O6 | 0.6886 (3) | 0.7118 (3) | 0.84539 (5) | 0.0164 (4) | |
O7 | 0.5199 (4) | 0.8762 (3) | 0.89191 (6) | 0.0251 (5) | |
C1 | 0.1872 (5) | 0.4312 (4) | 0.94156 (7) | 0.0152 (6) | |
C2 | 0.3442 (5) | 0.5291 (4) | 0.96376 (8) | 0.0177 (6) | |
H2 | 0.4890 | 0.5684 | 0.9536 | 0.021* | |
C3 | 0.2893 (6) | 0.5693 (4) | 1.00069 (8) | 0.0208 (6) | |
H3 | 0.3963 | 0.6364 | 1.0158 | 0.025* | |
C4 | 0.0783 (6) | 0.5115 (4) | 1.01552 (8) | 0.0207 (6) | |
H4 | 0.0423 | 0.5364 | 1.0410 | 0.025* | |
C5 | −0.0805 (5) | 0.4172 (4) | 0.99317 (8) | 0.0203 (6) | |
H5A | −0.2256 | 0.3789 | 1.0034 | 0.024* | |
C6 | −0.0289 (5) | 0.3787 (4) | 0.95618 (8) | 0.0183 (6) | |
H6 | −0.1395 | 0.3169 | 0.9408 | 0.022* | |
C7 | 0.2420 (5) | 0.3749 (4) | 0.90243 (7) | 0.0163 (6) | |
C8 | 0.5387 (5) | 0.3349 (4) | 0.85715 (7) | 0.0162 (6) | |
H8A | 0.4820 | 0.2058 | 0.8537 | 0.019* | |
H8B | 0.7108 | 0.3329 | 0.8558 | 0.019* | |
C9 | 0.4444 (5) | 0.4570 (4) | 0.82602 (7) | 0.0143 (6) | |
C10 | 0.2631 (5) | 0.3857 (4) | 0.80053 (7) | 0.0167 (6) | |
H10 | 0.1942 | 0.2615 | 0.8067 | 0.020* | |
C11 | 0.1072 (5) | 0.5236 (4) | 0.78182 (7) | 0.0177 (6) | |
H11 | −0.0640 | 0.5067 | 0.7856 | 0.021* | |
C12 | 0.1917 (5) | 0.7166 (4) | 0.77788 (7) | 0.0173 (6) | |
H12 | 0.0699 | 0.8160 | 0.7790 | 0.021* | |
C13 | 0.4278 (6) | 0.7684 (4) | 0.79357 (7) | 0.0170 (6) | |
H13 | 0.5530 | 0.7316 | 0.7756 | 0.020* | |
C14 | 0.4611 (5) | 0.6656 (4) | 0.83081 (7) | 0.0141 (6) | |
H14 | 0.3394 | 0.7078 | 0.8490 | 0.017* | |
C15 | 0.6928 (6) | 0.8232 (4) | 0.87612 (7) | 0.0183 (6) | |
C16 | 0.9378 (6) | 0.8664 (5) | 0.88744 (9) | 0.0274 (7) | |
H16A | 0.9366 | 0.9530 | 0.9087 | 0.041* | |
H16B | 1.0202 | 0.9235 | 0.8663 | 0.041* | |
H16C | 1.0169 | 0.7510 | 0.8947 | 0.041* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0167 (10) | 0.0203 (11) | 0.0112 (9) | −0.0012 (9) | 0.0016 (8) | 0.0001 (8) |
O2 | 0.0184 (11) | 0.0360 (13) | 0.0167 (10) | −0.0048 (10) | −0.0022 (9) | −0.0016 (9) |
O3 | 0.0193 (10) | 0.0184 (10) | 0.0120 (9) | 0.0009 (9) | 0.0021 (7) | −0.0031 (8) |
O4 | 0.0252 (11) | 0.0239 (11) | 0.0122 (9) | −0.0022 (10) | −0.0031 (8) | 0.0016 (8) |
O5 | 0.0331 (13) | 0.0125 (10) | 0.0202 (10) | −0.0010 (10) | 0.0035 (10) | 0.0003 (8) |
O6 | 0.0171 (10) | 0.0177 (10) | 0.0146 (9) | −0.0014 (9) | 0.0000 (8) | −0.0013 (8) |
O7 | 0.0250 (12) | 0.0321 (13) | 0.0182 (10) | 0.0011 (11) | 0.0004 (9) | −0.0079 (9) |
C1 | 0.0159 (13) | 0.0173 (14) | 0.0124 (12) | 0.0034 (12) | 0.0009 (11) | 0.0031 (10) |
C2 | 0.0170 (14) | 0.0161 (14) | 0.0201 (13) | −0.0001 (12) | 0.0029 (11) | 0.0032 (11) |
C3 | 0.0270 (16) | 0.0167 (14) | 0.0189 (14) | 0.0011 (13) | −0.0008 (12) | −0.0014 (11) |
C4 | 0.0282 (17) | 0.0182 (15) | 0.0158 (13) | 0.0065 (13) | 0.0048 (13) | 0.0011 (11) |
C5 | 0.0178 (15) | 0.0201 (16) | 0.0229 (15) | 0.0016 (12) | 0.0029 (12) | 0.0044 (11) |
C6 | 0.0152 (14) | 0.0208 (14) | 0.0190 (14) | 0.0000 (13) | −0.0029 (11) | 0.0042 (12) |
C7 | 0.0168 (14) | 0.0166 (14) | 0.0155 (13) | −0.0006 (12) | −0.0017 (11) | 0.0038 (11) |
C8 | 0.0170 (14) | 0.0183 (14) | 0.0132 (12) | 0.0021 (12) | 0.0000 (11) | 0.0006 (10) |
C9 | 0.0160 (13) | 0.0176 (14) | 0.0094 (12) | 0.0012 (12) | 0.0015 (10) | −0.0011 (10) |
C10 | 0.0178 (14) | 0.0186 (14) | 0.0137 (12) | −0.0004 (12) | 0.0004 (11) | −0.0015 (11) |
C11 | 0.0171 (14) | 0.0237 (15) | 0.0122 (12) | −0.0013 (12) | −0.0012 (11) | 0.0001 (11) |
C12 | 0.0207 (14) | 0.0203 (14) | 0.0110 (12) | 0.0057 (13) | −0.0010 (11) | 0.0009 (11) |
C13 | 0.0232 (15) | 0.0144 (14) | 0.0133 (12) | −0.0008 (12) | −0.0003 (12) | −0.0007 (10) |
C14 | 0.0131 (13) | 0.0173 (14) | 0.0120 (12) | 0.0001 (11) | 0.0017 (10) | −0.0005 (10) |
C15 | 0.0236 (15) | 0.0173 (15) | 0.0141 (13) | 0.0008 (13) | −0.0023 (12) | −0.0007 (11) |
C16 | 0.0241 (16) | 0.0281 (17) | 0.0300 (16) | −0.0003 (15) | −0.0067 (14) | −0.0071 (14) |
O1—C7 | 1.345 (3) | C5—C6 | 1.382 (4) |
O1—C8 | 1.448 (3) | C5—H5A | 0.9500 |
O2—C7 | 1.206 (3) | C6—H6 | 0.9500 |
O3—C9 | 1.451 (3) | C8—C9 | 1.515 (4) |
O3—C10 | 1.455 (3) | C8—H8A | 0.9900 |
O4—C12 | 1.455 (3) | C8—H8B | 0.9900 |
O4—C11 | 1.462 (3) | C9—C10 | 1.475 (4) |
O5—C13 | 1.418 (3) | C9—C14 | 1.509 (4) |
O5—H5 | 0.84 (3) | C10—C11 | 1.492 (4) |
O6—C15 | 1.358 (3) | C10—H10 | 1.0000 |
O6—C14 | 1.445 (3) | C11—C12 | 1.474 (4) |
O7—C15 | 1.204 (4) | C11—H11 | 1.0000 |
C1—C2 | 1.391 (4) | C12—C13 | 1.514 (4) |
C1—C6 | 1.398 (4) | C12—H12 | 1.0000 |
C1—C7 | 1.488 (4) | C13—C14 | 1.532 (4) |
C2—C3 | 1.386 (4) | C13—H13 | 1.0000 |
C2—H2 | 0.9500 | C14—H14 | 1.0000 |
C3—C4 | 1.387 (4) | C15—C16 | 1.497 (4) |
C3—H3 | 0.9500 | C16—H16A | 0.9800 |
C4—C5 | 1.388 (4) | C16—H16B | 0.9800 |
C4—H4 | 0.9500 | C16—H16C | 0.9800 |
C7—O1—C8 | 115.8 (2) | O3—C10—C11 | 116.3 (2) |
C9—O3—C10 | 61.00 (17) | C9—C10—C11 | 118.1 (3) |
C12—O4—C11 | 60.70 (18) | O3—C10—H10 | 116.9 |
C13—O5—H5 | 103 (3) | C9—C10—H10 | 116.9 |
C15—O6—C14 | 116.2 (2) | C11—C10—H10 | 116.9 |
C2—C1—C6 | 119.9 (3) | O4—C11—C12 | 59.43 (17) |
C2—C1—C7 | 122.3 (3) | O4—C11—C10 | 116.9 (2) |
C6—C1—C7 | 117.7 (3) | C12—C11—C10 | 117.9 (3) |
C3—C2—C1 | 120.0 (3) | O4—C11—H11 | 116.7 |
C3—C2—H2 | 120.0 | C12—C11—H11 | 116.7 |
C1—C2—H2 | 120.0 | C10—C11—H11 | 116.7 |
C2—C3—C4 | 120.0 (3) | O4—C12—C11 | 59.86 (18) |
C2—C3—H3 | 120.0 | O4—C12—C13 | 118.5 (2) |
C4—C3—H3 | 120.0 | C11—C12—C13 | 119.3 (2) |
C3—C4—C5 | 120.1 (3) | O4—C12—H12 | 115.9 |
C3—C4—H4 | 120.0 | C11—C12—H12 | 115.9 |
C5—C4—H4 | 120.0 | C13—C12—H12 | 115.9 |
C6—C5—C4 | 120.4 (3) | O5—C13—C12 | 110.3 (3) |
C6—C5—H5A | 119.8 | O5—C13—C14 | 108.3 (2) |
C4—C5—H5A | 119.8 | C12—C13—C14 | 108.3 (2) |
C5—C6—C1 | 119.6 (3) | O5—C13—H13 | 110.0 |
C5—C6—H6 | 120.2 | C12—C13—H13 | 110.0 |
C1—C6—H6 | 120.2 | C14—C13—H13 | 110.0 |
O2—C7—O1 | 123.2 (3) | O6—C14—C9 | 109.0 (2) |
O2—C7—C1 | 124.2 (3) | O6—C14—C13 | 108.4 (2) |
O1—C7—C1 | 112.6 (2) | C9—C14—C13 | 111.8 (2) |
O1—C8—C9 | 111.4 (2) | O6—C14—H14 | 109.2 |
O1—C8—H8A | 109.3 | C9—C14—H14 | 109.2 |
C9—C8—H8A | 109.3 | C13—C14—H14 | 109.2 |
O1—C8—H8B | 109.3 | O7—C15—O6 | 123.3 (3) |
C9—C8—H8B | 109.3 | O7—C15—C16 | 125.7 (3) |
H8A—C8—H8B | 108.0 | O6—C15—C16 | 110.9 (3) |
O3—C9—C10 | 59.64 (16) | C15—C16—H16A | 109.5 |
O3—C9—C14 | 115.2 (2) | C15—C16—H16B | 109.5 |
C10—C9—C14 | 117.3 (3) | H16A—C16—H16B | 109.5 |
O3—C9—C8 | 112.4 (2) | C15—C16—H16C | 109.5 |
C10—C9—C8 | 120.3 (3) | H16A—C16—H16C | 109.5 |
C14—C9—C8 | 117.9 (2) | H16B—C16—H16C | 109.5 |
O3—C10—C9 | 59.37 (17) | ||
C6—C1—C2—C3 | 2.1 (4) | O3—C10—C11—O4 | 23.0 (4) |
C7—C1—C2—C3 | −176.5 (3) | C9—C10—C11—O4 | 90.6 (3) |
C1—C2—C3—C4 | 0.2 (4) | O3—C10—C11—C12 | −44.9 (3) |
C2—C3—C4—C5 | −1.5 (4) | C9—C10—C11—C12 | 22.7 (4) |
C3—C4—C5—C6 | 0.6 (4) | C11—O4—C12—C13 | 109.2 (3) |
C4—C5—C6—C1 | 1.6 (4) | C10—C11—C12—O4 | 106.4 (3) |
C2—C1—C6—C5 | −2.9 (4) | O4—C11—C12—C13 | −107.9 (3) |
C7—C1—C6—C5 | 175.7 (3) | C10—C11—C12—C13 | −1.5 (4) |
C8—O1—C7—O2 | −4.1 (4) | O4—C12—C13—O5 | 133.7 (2) |
C8—O1—C7—C1 | 174.5 (2) | C11—C12—C13—O5 | −156.8 (2) |
C2—C1—C7—O2 | −171.5 (3) | O4—C12—C13—C14 | −107.9 (3) |
C6—C1—C7—O2 | 9.9 (4) | C11—C12—C13—C14 | −38.4 (3) |
C2—C1—C7—O1 | 9.9 (4) | C15—O6—C14—C9 | −128.9 (2) |
C6—C1—C7—O1 | −168.7 (2) | C15—O6—C14—C13 | 109.2 (2) |
C7—O1—C8—C9 | 72.9 (3) | O3—C9—C14—O6 | −93.0 (3) |
C10—O3—C9—C14 | −108.2 (3) | C10—C9—C14—O6 | −160.3 (2) |
C10—O3—C9—C8 | 113.0 (3) | C8—C9—C14—O6 | 43.4 (3) |
O1—C8—C9—O3 | −177.7 (2) | O3—C9—C14—C13 | 26.7 (4) |
O1—C8—C9—C10 | −110.8 (3) | C10—C9—C14—C13 | −40.6 (4) |
O1—C8—C9—C14 | 44.7 (4) | C8—C9—C14—C13 | 163.2 (2) |
C9—O3—C10—C11 | 108.5 (3) | O5—C13—C14—O6 | −61.7 (3) |
C14—C9—C10—O3 | 104.6 (3) | C12—C13—C14—O6 | 178.7 (2) |
C8—C9—C10—O3 | −99.8 (3) | O5—C13—C14—C9 | 178.2 (3) |
O3—C9—C10—C11 | −105.5 (3) | C12—C13—C14—C9 | 58.6 (3) |
C14—C9—C10—C11 | −0.9 (4) | C14—O6—C15—O7 | 3.2 (4) |
C8—C9—C10—C11 | 154.7 (3) | C14—O6—C15—C16 | −177.8 (2) |
C12—O4—C11—C10 | −108.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5···O4i | 0.84 (3) | 2.05 (3) | 2.887 (3) | 172 (4) |
Symmetry code: (i) −x+1, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C16H16O7 |
Mr | 320.29 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 100 |
a, b, c (Å) | 5.7451 (7), 7.1746 (9), 35.708 (5) |
V (Å3) | 1471.9 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.12 |
Crystal size (mm) | 0.35 × 0.05 × 0.05 |
Data collection | |
Diffractometer | Bruker SMART APEX |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14228, 2011, 1730 |
Rint | 0.073 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.117, 1.12 |
No. of reflections | 2011 |
No. of parameters | 213 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.37, −0.33 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5···O4i | 0.84 (3) | 2.05 (3) | 2.887 (3) | 172 (4) |
Symmetry code: (i) −x+1, y+1/2, −z+3/2. |
Acknowledgements
We thank the University of Malaya for supporting this study.
References
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Kaempferia rotunda is one of the four Malaysian Kaempferia of the Zingiberaceae family; among the constitutents isolated is 3-deacetylcrotepoxide (Scheme I), which was first reported by Pancharoen et al. (1996). 3-Deacetylcrotepoxide (Scheme I) features a six-membered cyclohexane ring that adopts a twisted boat conformation owing to the presence of two adjacent epoxide attachements that tie up four of the six axial positions. The CH3CO2– and HO– substituents occupy regular equatorial positions as each is connected to a methine carbon atom (Fig. 1). However, the bond angles at the ring carbon connected to the C6H5CO2CH2– substituent deviate signifcantly from the idealized tetrahedral angles as the carbon atom is part of an epoxide ring [112.4 (2), 117.9 (2), 120.3 (3) °].