7,8-Di­hydroxy-3-methyl-10-oxo-1H,10H-pyrano­[4,3-b]­chromene-9-carboxyl­ic acid

Wang, J.-F.; Zhang, Y.-J.; Fang, M.-J.; Huang, Y.-J.; Wei, Z.-B.; Zheng, Z.-H.; Su, W.-J.; Zhao, Y.-F.

doi:10.1107/S1600536803016714

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7,8-Dihydroxy-3-methyl-10-oxo-1H,10H-pyrano[4,3-b]chromene-9-carboxylic acid

J.-F. Wang, Y.-J. Zhang, M.-J. Fang, Y.-J. Huang, Z.-B. Wei, Z.-H. Zheng, W.-J. Su and Y.-F. Zhao

The structure of the title compound, anhydrofulvic acid, C₁₄H₁₀O₇, a yellow acidic metabolite isolated from Paecilomyces sp. was determined by X-ray analysis. The chromone ring system is essentially planar, with the carboxylic acid group coplanar with the ring.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803016714/ww6101sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536803016714/ww6101Isup2.hkl Contains datablock I

CCDC reference: 222842

checkCIF report

Key indicators

Single-crystal X-ray study
T = 296 K
Mean (C-C) = 0.002 Å
R factor = 0.037
wR factor = 0.119
Data-to-parameter ratio = 13.0

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT028_ALERT_3_B _diffrn_measured_fraction_theta_max  Low .....       0.95

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical          ?
PLAT147_ALERT_1_C su on Symmetry Constrained Cell Angle(s) .....          ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O5     -   C14    =       6.06 su

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

   2 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
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

Comment top

The title compound, (I), had been prepared by dehydration of a natural product, fulvic acid [3,7,8-trihydroxy-3-methyl-10-oxo-4,10-dihydro-1H,3H-pyrano[4,3-b]chromene- 9-carboxylic acid, (II)], isolated from several fungi (Dean, 1957). In this study, (I) was isolated from the fermentation broth of Paecilomyces sp., an endophytic fungi of Cephalataxus fortunei, and its structure was determined by X-ray analysis.

The chromone ring system of (I) is essentially planar, with the hydroxyl and carboxylic acid groups coplanar with the ring. There is one intermolecular hydrogen bond and three intramolecular hydrogen bonds in the crystal structure (Table 2), which make the crystal very stable (m.p. 516–518 K).

Experimental top

The title compound, (I) was isolated from the organic extract of the liquid culture of the Paecilomyces sp. Recrystallization from ethyl acetate afforded green crystals suitable for X-ray analysis. The molecular formula of (I) was deduced from the high resolution ESI–MS spectrum as C₁₄H₁₀O₇, showing an accurate mass at m/z 291.0501 [M + H]⁺. The ¹³C NMR analysis revealed 14 carbons: δ (p.p.m.) = 20.0 (C13), 64.3(C12), 94.5 (C10), 101.3 (C4), 103.358 (C8), 113.0 (C6), 118.0 (C1), 143.5 (C2), 149.8 (C3), 152.0 (C5), 158.6 (C9), 167.6 (C11), 168.8 (C14) and 171.3 (C7).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1998); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

Figures top

Fig. 1. ORTEP-3 (Farrugia, 1997) plot of the structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.

7,8-Dihydroxy-3-methyl-10-oxo-1H,10H-pyrano[4,3-b]chromene-9-carboxylic acid top

Crystal data top

C₁₄H₁₀O₇	F(000) = 600
M_r = 290.22	D_x = 1.617 Mg m⁻³
Monoclinic, P2₁/c	Melting point = 516–518 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71069 Å
a = 7.814 (5) Å	Cell parameters from 2225 reflections
b = 10.085 (5) Å	θ = 2.4–27.5°
c = 15.124 (5) Å	µ = 0.13 mm⁻¹
β = 90.178 (5)°	T = 296 K
V = 1191.8 (10) Å³	Chunk, green
Z = 4	0.20 × 0.18 × 0.10 mm

Data collection top

Bruker AXS area-detector diffractometer	2615 independent reflections
Radiation source: fine-focus sealed tube	2225 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.000
ϕ and ω scans	θ_max = 27.5°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.974, T_max = 0.987	k = 0→13
2615 measured reflections	l = −19→0

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.119	w = 1/[σ²(F_o²) + (0.0758P)² + 0.0975P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max < 0.001
2615 reflections	Δρ_max = 0.24 e Å⁻³
201 parameters	Δρ_min = −0.20 e Å⁻³
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.013 (3)

Crystal data top

C₁₄H₁₀O₇	V = 1191.8 (10) Å³
M_r = 290.22	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.814 (5) Å	µ = 0.13 mm⁻¹
b = 10.085 (5) Å	T = 296 K
c = 15.124 (5) Å	0.20 × 0.18 × 0.10 mm
β = 90.178 (5)°

Data collection top

Bruker AXS area-detector diffractometer	2615 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2225 reflections with I > 2σ(I)
T_min = 0.974, T_max = 0.987	R_int = 0.000
2615 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.119	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	Δρ_max = 0.24 e Å⁻³
2615 reflections	Δρ_min = −0.20 e Å⁻³
201 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.78838 (13)	0.14646 (9)	0.63238 (5)	0.0384 (2)
C1	0.84098 (14)	0.06547 (12)	0.39489 (7)	0.0310 (3)
O2	0.48841 (13)	−0.14163 (10)	0.73806 (6)	0.0446 (3)
C2	0.92692 (15)	0.18227 (13)	0.37272 (7)	0.0332 (3)
O3	0.64067 (14)	−0.16488 (10)	0.47837 (6)	0.0477 (3)
C3	0.96229 (16)	0.28357 (12)	0.43593 (8)	0.0363 (3)
O4	0.87828 (14)	−0.00461 (10)	0.24704 (6)	0.0486 (3)
C4	0.91286 (17)	0.26637 (13)	0.52140 (8)	0.0385 (3)
O5	0.73718 (16)	−0.14121 (11)	0.33084 (7)	0.0573 (3)
C5	0.82745 (16)	0.15028 (12)	0.54437 (7)	0.0321 (3)
O6	0.98542 (13)	0.21222 (10)	0.29248 (6)	0.0440 (3)
C6	0.78576 (14)	0.04765 (12)	0.48533 (7)	0.0297 (3)
O7	1.04580 (15)	0.39362 (10)	0.41172 (6)	0.0511 (3)
C7	0.69266 (15)	−0.06445 (12)	0.52273 (8)	0.0327 (3)
C8	0.65930 (15)	−0.06322 (12)	0.61391 (7)	0.0332 (3)
C9	0.70915 (16)	0.03979 (13)	0.66582 (8)	0.0340 (3)
C10	0.67352 (18)	0.04178 (14)	0.75777 (8)	0.0400 (3)
C11	0.56121 (17)	−0.04719 (13)	0.78941 (8)	0.0393 (3)
C12	0.57850 (18)	−0.17989 (13)	0.65946 (8)	0.0398 (3)
C13	0.4922 (2)	−0.04747 (16)	0.88069 (9)	0.0532 (4)
C14	0.81714 (17)	−0.03259 (14)	0.32080 (8)	0.0383 (3)
H4A	0.9357	0.3310	0.5637	0.046*
H5	0.687 (3)	−0.156 (2)	0.4038 (8)	0.086*
H6	0.952 (2)	0.138 (2)	0.2601 (12)	0.066*
H7	1.066 (3)	0.393 (2)	0.3574 (15)	0.077*
H10A	0.7263	0.1028	0.7950	0.048*
H12A	0.4994	−0.2229	0.6191	0.048*
H12B	0.6668	−0.2435	0.6749	0.048*
H13A	0.5534	0.0161	0.9159	0.080*
H13B	0.5055	−0.1342	0.9060	0.080*
H13C	0.3730	−0.0245	0.8792	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0535 (5)	0.0374 (5)	0.0244 (4)	−0.0101 (4)	0.0063 (3)	−0.0020 (3)
C1	0.0342 (6)	0.0337 (6)	0.0252 (5)	0.0058 (5)	0.0004 (4)	−0.0023 (4)
O2	0.0499 (5)	0.0407 (5)	0.0434 (5)	−0.0048 (4)	0.0141 (4)	0.0014 (4)
C2	0.0387 (6)	0.0363 (6)	0.0246 (5)	0.0065 (5)	0.0019 (4)	0.0022 (4)
O3	0.0620 (6)	0.0400 (5)	0.0410 (5)	−0.0149 (5)	0.0075 (4)	−0.0107 (4)
C3	0.0447 (7)	0.0332 (6)	0.0310 (6)	−0.0014 (5)	0.0039 (5)	0.0038 (4)
O4	0.0673 (7)	0.0490 (6)	0.0297 (4)	0.0057 (5)	0.0094 (4)	−0.0084 (4)
C4	0.0525 (7)	0.0346 (6)	0.0284 (6)	−0.0065 (6)	0.0041 (5)	−0.0031 (4)
O5	0.0764 (8)	0.0546 (7)	0.0409 (5)	−0.0211 (6)	0.0112 (5)	−0.0197 (4)
C5	0.0389 (6)	0.0339 (6)	0.0236 (5)	0.0003 (5)	0.0026 (4)	−0.0003 (4)
O6	0.0614 (6)	0.0441 (5)	0.0264 (4)	0.0013 (5)	0.0102 (4)	0.0026 (4)
C6	0.0316 (5)	0.0309 (6)	0.0266 (5)	0.0035 (5)	0.0004 (4)	−0.0004 (4)
O7	0.0794 (7)	0.0416 (5)	0.0324 (4)	−0.0169 (5)	0.0130 (5)	0.0021 (4)
C7	0.0337 (6)	0.0321 (6)	0.0322 (6)	0.0020 (5)	0.0006 (4)	−0.0024 (4)
C8	0.0354 (6)	0.0320 (6)	0.0323 (6)	0.0015 (5)	0.0029 (4)	0.0023 (4)
C9	0.0379 (6)	0.0343 (6)	0.0299 (5)	−0.0006 (5)	0.0035 (4)	0.0033 (4)
C10	0.0490 (7)	0.0436 (7)	0.0274 (6)	−0.0035 (6)	0.0039 (5)	0.0000 (5)
C11	0.0462 (7)	0.0381 (7)	0.0337 (6)	0.0062 (5)	0.0056 (5)	0.0059 (5)
C12	0.0466 (7)	0.0332 (6)	0.0396 (6)	−0.0006 (6)	0.0087 (5)	0.0017 (5)
C13	0.0703 (9)	0.0509 (8)	0.0387 (7)	0.0033 (7)	0.0180 (6)	0.0096 (6)
C14	0.0425 (6)	0.0426 (7)	0.0298 (6)	0.0072 (6)	0.0005 (5)	−0.0075 (5)

Geometric parameters (Å, º) top

O1—C9	1.3410 (16)	C7—C8	1.4044 (16)
O1—C5	1.3671 (14)	C8—C9	1.3585 (18)
C1—C2	1.3972 (18)	C8—C12	1.5034 (18)
C1—C6	1.4468 (15)	C9—C10	1.4192 (16)
C1—C14	1.5057 (16)	C10—C11	1.344 (2)
O2—C11	1.3531 (18)	C11—C13	1.4838 (17)
O2—C12	1.4362 (16)	O3—H5	1.189 (10)
C2—O6	1.3329 (14)	C4—H4A	0.9300
C2—C3	1.4257 (18)	O5—H5	1.182 (9)
O3—C7	1.2802 (15)	O6—H6	0.93 (2)
C3—O7	1.3391 (16)	O7—H7	0.84 (2)
C3—C4	1.3613 (16)	C10—H10A	0.9300
O4—C14	1.2473 (16)	C12—H12A	0.9700
C4—C5	1.3922 (18)	C12—H12B	0.9700
O5—C14	1.2704 (18)	C13—H13A	0.9600
C5—C6	1.4046 (16)	C13—H13B	0.9600
C6—C7	1.4594 (17)	C13—H13C	0.9600

C9—O1—C5	119.65 (9)	C11—C10—C9	118.01 (12)
C2—C1—C6	118.46 (10)	C10—C11—O2	122.64 (11)
O6—C2—C1	125.17 (11)	C10—C11—C13	124.90 (13)
O6—C2—C3	112.45 (11)	O2—C11—C13	112.29 (12)
C1—C2—C3	122.38 (10)	O2—C12—C8	112.12 (11)
O7—C3—C4	120.34 (11)	O4—C14—O5	119.47 (11)
O7—C3—C2	120.28 (11)	O4—C14—C1	118.04 (13)
C4—C3—C2	119.37 (11)	O5—C14—C1	122.49 (11)
C3—C4—C5	118.80 (11)	C3—C4—H4A	120.6
O1—C5—C4	112.05 (10)	C5—C4—H4A	120.6
O1—C5—C6	123.10 (10)	C7—O3—H5	109.9 (11)
C4—C5—C6	124.85 (10)	C14—O5—H5	112.6 (11)
C5—C6—C1	116.12 (11)	C2—O6—H6	101.6 (12)
C5—C6—C7	116.07 (10)	C3—O7—H7	111.2 (16)
C1—C6—C7	127.81 (10)	C11—C10—H10A	121.0
O3—C7—C8	117.51 (11)	C9—C10—H10A	121.0
O3—C7—C6	124.58 (11)	O2—C12—H12A	109.2
C8—C7—C6	117.90 (10)	C8—C12—H12A	109.2
C9—C8—C7	121.37 (11)	O2—C12—H12B	109.2
C9—C8—C12	116.98 (11)	C8—C12—H12B	109.2
C7—C8—C12	121.50 (11)	H12A—C12—H12B	107.9
O1—C9—C8	121.83 (11)	C11—C13—H13A	109.5
O1—C9—C10	116.77 (11)	C11—C13—H13B	109.5
C8—C9—C10	121.35 (11)	H13A—C13—H13B	109.5
C2—C1—C14	115.70 (10)	C11—C13—H13C	109.5
C6—C1—C14	125.84 (11)	H13A—C13—H13C	109.5
C11—O2—C12	117.25 (10)	H13B—C13—H13C	109.5

C6—C1—C2—O6	179.85 (11)	C1—C6—C7—C8	177.05 (11)
C14—C1—C2—O6	0.86 (18)	O3—C7—C8—C9	−179.64 (11)
C6—C1—C2—C3	0.23 (18)	C6—C7—C8—C9	1.11 (18)
C14—C1—C2—C3	−178.77 (11)	O3—C7—C8—C12	4.87 (18)
O6—C2—C3—O7	0.01 (18)	C6—C7—C8—C12	−174.38 (10)
C1—C2—C3—O7	179.68 (11)	C5—O1—C9—C8	−2.91 (18)
O6—C2—C3—C4	−178.92 (11)	C5—O1—C9—C10	179.52 (11)
C1—C2—C3—C4	0.75 (19)	C7—C8—C9—O1	1.74 (19)
O7—C3—C4—C5	−179.51 (12)	C12—C8—C9—O1	177.42 (11)
C2—C3—C4—C5	−0.58 (19)	C7—C8—C9—C10	179.19 (12)
C9—O1—C5—C4	−178.53 (11)	C12—C8—C9—C10	−5.12 (18)
C9—O1—C5—C6	1.19 (18)	O1—C9—C10—C11	164.87 (12)
C3—C4—C5—O1	179.12 (11)	C8—C9—C10—C11	−12.7 (2)
C3—C4—C5—C6	−0.6 (2)	C9—C10—C11—O2	3.4 (2)
O1—C5—C6—C1	−178.16 (10)	C9—C10—C11—C13	−171.42 (13)
C4—C5—C6—C1	1.53 (18)	C12—O2—C11—C10	23.91 (18)
O1—C5—C6—C7	1.56 (17)	C12—O2—C11—C13	−160.72 (12)
C4—C5—C6—C7	−178.76 (12)	C11—O2—C12—C8	−39.37 (15)
C2—C1—C6—C5	−1.28 (16)	C9—C8—C12—O2	30.09 (16)
C14—C1—C6—C5	177.60 (11)	C7—C8—C12—O2	−154.23 (12)
C2—C1—C6—C7	179.04 (11)	C2—C1—C14—O4	1.73 (17)
C14—C1—C6—C7	−2.1 (2)	C6—C1—C14—O4	−177.18 (11)
C5—C6—C7—O3	178.19 (11)	C2—C1—C14—O5	−177.98 (12)
C1—C6—C7—O3	−2.1 (2)	C6—C1—C14—O5	3.1 (2)
C5—C6—C7—C8	−2.62 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···O3	1.18 (1)	1.19 (1)	2.3696 (15)	177 (2)
O6—H6···O4	0.93 (2)	1.56 (2)	2.4395 (18)	155.4 (18)
O7—H7···O6	0.84 (2)	2.17 (2)	2.6108 (16)	113.0 (19)
O7—H7···O4ⁱ	0.84 (2)	1.94 (2)	2.6794 (15)	147 (2)

Symmetry code: (i) −x+2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₀O₇
M_r	290.22
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	7.814 (5), 10.085 (5), 15.124 (5)
β (°)	90.178 (5)
V (Å³)	1191.8 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.13
Crystal size (mm)	0.20 × 0.18 × 0.10

Data collection
Diffractometer	Bruker AXS area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.974, 0.987
No. of measured, independent and observed [I > 2σ(I)] reflections	2615, 2615, 2225
R_int	0.000
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.119, 1.09
No. of reflections	2615
No. of parameters	201
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.20

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SAINT, SIR97 (Altomare et al., 1998), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997), SHELXL97.

Selected geometric parameters (Å, º) top

O1—C9	1.3410 (16)	O4—C14	1.2473 (16)
O1—C5	1.3671 (14)	C4—C5	1.3922 (18)
C1—C2	1.3972 (18)	O5—C14	1.2704 (18)
C1—C6	1.4468 (15)	C5—C6	1.4046 (16)
C1—C14	1.5057 (16)	C6—C7	1.4594 (17)
O2—C11	1.3531 (18)	C7—C8	1.4044 (16)
O2—C12	1.4362 (16)	C8—C9	1.3585 (18)
C2—O6	1.3329 (14)	C8—C12	1.5034 (18)
C2—C3	1.4257 (18)	C9—C10	1.4192 (16)
O3—C7	1.2802 (15)	C10—C11	1.344 (2)
C3—O7	1.3391 (16)	C11—C13	1.4838 (17)
C3—C4	1.3613 (16)

C9—O1—C5	119.65 (9)	C9—C8—C7	121.37 (11)
C2—C1—C6	118.46 (10)	C9—C8—C12	116.98 (11)
O6—C2—C1	125.17 (11)	C7—C8—C12	121.50 (11)
O6—C2—C3	112.45 (11)	O1—C9—C8	121.83 (11)
C1—C2—C3	122.38 (10)	O1—C9—C10	116.77 (11)
O7—C3—C4	120.34 (11)	C8—C9—C10	121.35 (11)
O7—C3—C2	120.28 (11)	C2—C1—C14	115.70 (10)
C4—C3—C2	119.37 (11)	C6—C1—C14	125.84 (11)
C3—C4—C5	118.80 (11)	C11—O2—C12	117.25 (10)
O1—C5—C4	112.05 (10)	C11—C10—C9	118.01 (12)
O1—C5—C6	123.10 (10)	C10—C11—O2	122.64 (11)
C4—C5—C6	124.85 (10)	C10—C11—C13	124.90 (13)
C5—C6—C1	116.12 (11)	O2—C11—C13	112.29 (12)
C5—C6—C7	116.07 (10)	O2—C12—C8	112.12 (11)
C1—C6—C7	127.81 (10)	O4—C14—O5	119.47 (11)
O3—C7—C8	117.51 (11)	O4—C14—C1	118.04 (13)
O3—C7—C6	124.58 (11)	O5—C14—C1	122.49 (11)
C8—C7—C6	117.90 (10)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···O3	1.18 (1)	1.19 (1)	2.3696 (15)	177 (2)
O6—H6···O4	0.93 (2)	1.56 (2)	2.4395 (18)	155.4 (18)
O7—H7···O6	0.84 (2)	2.17 (2)	2.6108 (16)	113.0 (19)
O7—H7···O4ⁱ	0.84 (2)	1.94 (2)	2.6794 (15)	147 (2)

Symmetry code: (i) −x+2, y+1/2, −z+1/2.

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