4-(1,1-Dimethylprop-2-en­yl)-1,3,5-trihydr­oxy-2-(3-methyl­but-2-en­yl)-9H-xanthen-9-one

The title compound, also known as allanxanthone A, C₂₃H₂₄O₅, was isolated from the medicinal plant Allanblackia monticola (Clusiaceae). The 9H-xanthen-9-one system is essentially planar. The crystal structure is stabilized by intra- and inter­molecular hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.048
• wR factor = 0.134
• Data-to-parameter ratio = 12.7

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT420_ALERT_2_B D-H Without Acceptor       O3     -   H3     ...          ?

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

---

Computing details

Data collection: COLLECT (Bruker, 2004); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997\bbr01); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Siemens, 1990); software used to prepare material for publication: SHELXL97.

4-(1,1-dimethyl-2-prop-2-enyl)-1,3,5-trihydroxy-2-(3-methylbut-2-enyl)-9H-xanthen-9-one

Crystal data

C23H24O5	Dx = 1.341 Mg m^−3
Mr = 380.42	Melting point: 179 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 12.9715 (8) Å	Cell parameters from 17865 reflections
b = 14.6160 (8) Å	θ = 2.9–25.0°
c = 10.0330 (5) Å	µ = 0.09 mm^−1
β = 97.739 (3)°	T = 100 K
V = 1884.85 (18) Å^3	Needle, light yellow
Z = 4	0.30 × 0.08 × 0.02 mm
F(000) = 808

Data collection

Nonius KappaCCD diffractometer	3296 independent reflections
Radiation source: fine-focus sealed tube	2259 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.070
CCD scans	θmax = 25.0°, θmin = 3.2°
Absorption correction: multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1997)	h = −15→15
Tmin = 0.972, Tmax = 0.998	k = −16→17
20114 measured reflections	l = −11→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.134	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0771P)^2 + 0.0324P] where P = (Fo^2 + 2Fc^2)/3
3296 reflections	(Δ/σ)max < 0.001
260 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.53914 (11)	0.51704 (9)	0.30562 (14)	0.0263 (4)
H1	0.4895	0.4870	0.3293	0.039*
O2	0.63867 (10)	0.62125 (9)	0.15454 (12)	0.0221 (3)
O3	0.89840 (12)	0.62945 (10)	−0.13749 (14)	0.0329 (4)
H3	0.8931	0.5722	−0.1347	0.049*
O4	0.75453 (11)	0.90466 (9)	−0.01881 (14)	0.0261 (4)
H4	0.7091	0.9250	0.0256	0.039*
O5	0.61155 (11)	0.90046 (9)	0.13688 (12)	0.0241 (3)
C1	0.48170 (17)	0.79730 (13)	0.2950 (2)	0.0247 (5)
H1A	0.4706	0.8616	0.2940	0.030*
C2	0.42530 (16)	0.74168 (14)	0.3685 (2)	0.0267 (5)
H2	0.3742	0.7677	0.4165	0.032*
C3	0.44220 (16)	0.64693 (13)	0.3738 (2)	0.0253 (5)
H3A	0.4029	0.6095	0.4257	0.030*
C4	0.51559 (16)	0.60774 (13)	0.30399 (19)	0.0222 (5)
C5	0.57083 (15)	0.66519 (13)	0.22619 (18)	0.0203 (5)
C6	0.69541 (15)	0.66932 (13)	0.07252 (18)	0.0200 (5)
C7	0.75723 (15)	0.61667 (13)	−0.00224 (18)	0.0213 (5)
C8	0.82543 (16)	0.66819 (14)	−0.06997 (19)	0.0230 (5)
C9	0.82763 (15)	0.76433 (13)	−0.07515 (18)	0.0216 (5)
C10	0.75815 (16)	0.81244 (13)	−0.00870 (18)	0.0211 (5)
C11	0.69104 (15)	0.76573 (13)	0.06992 (18)	0.0210 (5)
C12	0.61968 (15)	0.81416 (13)	0.14241 (18)	0.0202 (5)
C13	0.55570 (15)	0.75917 (13)	0.22135 (18)	0.0206 (5)
C14	0.75350 (16)	0.51077 (13)	−0.00389 (19)	0.0246 (5)
C15	0.8181 (2)	0.47420 (15)	0.1219 (2)	0.0367 (6)
H15A	0.8139	0.4073	0.1226	0.055*
H15B	0.7914	0.4987	0.2015	0.055*
H15C	0.8907	0.4930	0.1229	0.055*
C16	0.64063 (18)	0.47360 (15)	−0.0137 (2)	0.0350 (6)
H16A	0.6393	0.4094	−0.0423	0.052*
H16B	0.5950	0.5097	−0.0795	0.052*
H16C	0.6164	0.4782	0.0744	0.052*
C17	0.78859 (19)	0.47269 (14)	−0.1323 (2)	0.0344 (6)
H17	0.7514	0.4928	−0.2152	0.041*
C18	0.8661 (2)	0.41416 (16)	−0.1394 (3)	0.0464 (7)
H18A	0.9057	0.3920	−0.0593	0.056*
H18B	0.8820	0.3944	−0.2245	0.056*
C19	0.90352 (17)	0.81219 (14)	−0.1548 (2)	0.0265 (5)
H19A	0.8914	0.7901	−0.2489	0.032*
H19B	0.8888	0.8787	−0.1561	0.032*
C20	1.01701 (17)	0.79738 (14)	−0.1000 (2)	0.0296 (5)
H20	1.0546	0.7555	−0.1475	0.035*
C21	1.06878 (18)	0.83671 (15)	0.0070 (2)	0.0309 (5)
C22	1.01953 (18)	0.90086 (16)	0.0977 (2)	0.0343 (6)
H22A	0.9477	0.9136	0.0585	0.051*
H22B	1.0590	0.9582	0.1074	0.051*
H22C	1.0199	0.8725	0.1863	0.051*
C23	1.18282 (18)	0.81956 (17)	0.0499 (3)	0.0438 (6)
H23A	1.2094	0.7783	−0.0145	0.066*
H23B	1.1926	0.7915	0.1395	0.066*
H23C	1.2207	0.8777	0.0528	0.066*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0285 (9)	0.0174 (7)	0.0350 (8)	−0.0031 (6)	0.0115 (6)	0.0012 (6)
O2	0.0239 (8)	0.0178 (7)	0.0261 (7)	−0.0004 (6)	0.0093 (6)	−0.0007 (6)
O3	0.0373 (10)	0.0258 (8)	0.0401 (9)	0.0022 (7)	0.0215 (7)	−0.0030 (7)
O4	0.0279 (9)	0.0169 (7)	0.0350 (8)	0.0003 (6)	0.0098 (6)	0.0015 (6)
O5	0.0268 (8)	0.0163 (8)	0.0300 (8)	0.0008 (6)	0.0066 (6)	−0.0006 (5)
C1	0.0285 (12)	0.0185 (11)	0.0274 (11)	0.0007 (9)	0.0049 (9)	−0.0011 (8)
C2	0.0247 (12)	0.0264 (12)	0.0307 (12)	0.0021 (9)	0.0093 (9)	−0.0030 (9)
C3	0.0250 (12)	0.0266 (12)	0.0253 (11)	−0.0032 (9)	0.0075 (9)	0.0003 (8)
C4	0.0242 (12)	0.0193 (11)	0.0231 (10)	−0.0022 (8)	0.0036 (8)	−0.0010 (8)
C5	0.0203 (11)	0.0215 (11)	0.0193 (10)	−0.0006 (8)	0.0032 (8)	−0.0022 (8)
C6	0.0186 (11)	0.0189 (10)	0.0222 (11)	−0.0028 (8)	0.0021 (8)	0.0025 (8)
C7	0.0229 (12)	0.0180 (11)	0.0223 (10)	−0.0003 (8)	0.0010 (8)	−0.0009 (8)
C8	0.0240 (12)	0.0252 (11)	0.0202 (10)	0.0027 (9)	0.0041 (9)	−0.0024 (8)
C9	0.0219 (11)	0.0221 (11)	0.0207 (11)	−0.0006 (9)	0.0018 (8)	0.0013 (8)
C10	0.0224 (12)	0.0172 (10)	0.0228 (11)	−0.0008 (8)	−0.0010 (8)	0.0009 (8)
C11	0.0207 (11)	0.0207 (11)	0.0210 (11)	0.0007 (8)	0.0007 (8)	0.0001 (8)
C12	0.0211 (11)	0.0193 (11)	0.0194 (10)	0.0004 (8)	−0.0007 (8)	−0.0009 (8)
C13	0.0214 (11)	0.0183 (10)	0.0214 (10)	−0.0006 (8)	0.0010 (8)	−0.0017 (8)
C14	0.0277 (13)	0.0193 (11)	0.0281 (11)	0.0016 (9)	0.0080 (9)	−0.0019 (8)
C15	0.0462 (16)	0.0263 (12)	0.0362 (13)	0.0054 (11)	0.0008 (10)	−0.0006 (10)
C16	0.0365 (14)	0.0266 (12)	0.0424 (13)	−0.0029 (10)	0.0073 (11)	−0.0029 (10)
C17	0.0413 (15)	0.0276 (12)	0.0362 (12)	−0.0038 (11)	0.0121 (10)	−0.0024 (10)
C18	0.0597 (19)	0.0300 (14)	0.0556 (17)	0.0042 (12)	0.0307 (13)	−0.0065 (11)
C19	0.0317 (13)	0.0222 (11)	0.0271 (11)	−0.0009 (9)	0.0090 (9)	0.0011 (8)
C20	0.0297 (13)	0.0245 (12)	0.0376 (13)	−0.0016 (9)	0.0156 (10)	0.0009 (9)
C21	0.0299 (13)	0.0281 (12)	0.0360 (13)	−0.0013 (10)	0.0089 (10)	0.0059 (10)
C22	0.0335 (14)	0.0396 (14)	0.0300 (12)	−0.0015 (11)	0.0053 (10)	0.0010 (10)
C23	0.0273 (14)	0.0464 (15)	0.0584 (16)	−0.0044 (11)	0.0080 (11)	−0.0037 (12)

Geometric parameters (Å, º)

O1—C4	1.360 (2)	C12—C13	1.462 (3)
O1—H1	0.8400	C14—C15	1.515 (3)
O2—C5	1.369 (2)	C14—C17	1.528 (3)
O2—C6	1.370 (2)	C14—C16	1.552 (3)
O3—C8	1.359 (2)	C15—H15A	0.9800
O3—H3	0.8400	C15—H15B	0.9800
O4—C10	1.352 (2)	C15—H15C	0.9800
O4—H4	0.8400	C16—H16A	0.9800
O5—C12	1.266 (2)	C16—H16B	0.9800
C1—C2	1.373 (3)	C16—H16C	0.9800
C1—C13	1.403 (3)	C17—C18	1.330 (3)
C1—H1A	0.9500	C17—H17	0.9500
C2—C3	1.402 (3)	C18—H18A	0.9500
C2—H2	0.9500	C18—H18B	0.9500
C3—C4	1.380 (3)	C19—C20	1.516 (3)
C3—H3A	0.9500	C19—H19A	0.9900
C4—C5	1.406 (3)	C19—H19B	0.9900
C5—C13	1.388 (3)	C20—C21	1.318 (3)
C6—C7	1.400 (3)	C20—H20	0.9500
C6—C11	1.410 (3)	C21—C23	1.505 (3)
C7—C8	1.405 (3)	C21—C22	1.508 (3)
C7—C14	1.549 (3)	C22—H22A	0.9800
C8—C9	1.407 (3)	C22—H22B	0.9800
C9—C10	1.383 (3)	C22—H22C	0.9800
C9—C19	1.520 (3)	C23—H23A	0.9800
C10—C11	1.425 (3)	C23—H23B	0.9800
C11—C12	1.438 (3)	C23—H23C	0.9800
C4—O1—H1	109.5	C15—C14—C16	109.91 (18)
C5—O2—C6	120.69 (15)	C17—C14—C16	101.80 (17)
C8—O3—H3	109.5	C7—C14—C16	112.23 (16)
C10—O4—H4	109.5	C14—C15—H15A	109.5
C2—C1—C13	119.96 (18)	C14—C15—H15B	109.5
C2—C1—H1A	120.0	H15A—C15—H15B	109.5
C13—C1—H1A	120.0	C14—C15—H15C	109.5
C1—C2—C3	120.87 (19)	H15A—C15—H15C	109.5
C1—C2—H2	119.6	H15B—C15—H15C	109.5
C3—C2—H2	119.6	C14—C16—H16A	109.5
C4—C3—C2	120.40 (18)	C14—C16—H16B	109.5
C4—C3—H3A	119.8	H16A—C16—H16B	109.5
C2—C3—H3A	119.8	C14—C16—H16C	109.5
O1—C4—C3	124.59 (17)	H16A—C16—H16C	109.5
O1—C4—C5	117.27 (17)	H16B—C16—H16C	109.5
C3—C4—C5	118.14 (18)	C18—C17—C14	126.3 (2)
O2—C5—C13	122.94 (17)	C18—C17—H17	116.8
O2—C5—C4	115.02 (17)	C14—C17—H17	116.8
C13—C5—C4	122.03 (18)	C17—C18—H18A	120.0
O2—C6—C7	115.65 (17)	C17—C18—H18B	120.0
O2—C6—C11	120.01 (17)	H18A—C18—H18B	120.0
C7—C6—C11	124.32 (18)	C20—C19—C9	114.17 (16)
C6—C7—C8	114.08 (17)	C20—C19—H19A	108.7
C6—C7—C14	122.40 (17)	C9—C19—H19A	108.7
C8—C7—C14	123.47 (17)	C20—C19—H19B	108.7
O3—C8—C7	122.94 (18)	C9—C19—H19B	108.7
O3—C8—C9	112.26 (17)	H19A—C19—H19B	107.6
C7—C8—C9	124.79 (18)	C21—C20—C19	126.6 (2)
C10—C9—C8	118.19 (18)	C21—C20—H20	116.7
C10—C9—C19	122.00 (18)	C19—C20—H20	116.7
C8—C9—C19	119.80 (17)	C20—C21—C23	122.3 (2)
O4—C10—C9	119.28 (17)	C20—C21—C22	123.5 (2)
O4—C10—C11	120.09 (17)	C23—C21—C22	114.24 (19)
C9—C10—C11	120.63 (18)	C21—C22—H22A	109.5
C6—C11—C10	117.57 (17)	C21—C22—H22B	109.5
C6—C11—C12	120.63 (17)	H22A—C22—H22B	109.5
C10—C11—C12	121.80 (18)	C21—C22—H22C	109.5
O5—C12—C11	121.57 (17)	H22A—C22—H22C	109.5
O5—C12—C13	121.41 (17)	H22B—C22—H22C	109.5
C11—C12—C13	117.02 (17)	C21—C23—H23A	109.5
C5—C13—C1	118.57 (17)	C21—C23—H23B	109.5
C5—C13—C12	118.37 (17)	H23A—C23—H23B	109.5
C1—C13—C12	123.04 (17)	C21—C23—H23C	109.5
C15—C14—C17	112.32 (18)	H23A—C23—H23C	109.5
C15—C14—C7	109.31 (16)	H23B—C23—H23C	109.5
C17—C14—C7	111.13 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O5^i	0.84	1.88	2.713 (2)	169
O4—H4···O5	0.84	1.83	2.581 (2)	148
C1—H1A···O1^ii	0.95	2.48	3.367 (2)	155

Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+1, y+1/2, −z+1/2.