Oosporein from Tremella fuciformis

Abstract

The title compound [systematic name: 3,3′,6,6′-tetra­hydroxy-4,4′-dimethyl-1,1′-bi(cyclo­hexa-3,6-diene)-2,2′,5,5′-tetra­one], C₁₄H₁₀O₈, was isolated from Tremella fuciformis. The mol­ecule has 2 symmetry, with the mid-point of the C—C bond linking the cyclo­hexa­dienedione rings located on a twofold rotation axis. In the mol­ecule, the ring is approximately planar, with an r.m.s. deviation of 0.0093 Å, and the two rings make a dihedral angle of 67.89 (5)°. Inter­molecular O—H⋯O hydrogen bonding occurs in the crystal structure.

Related literature  

For general background to the title compound, see: Takeshita & Anchel (1965 ▶). For the chemical structure of the title compound established from NMR data, see: Richard et al. (1974 ▶).

Experimental  

Crystal data  

• C₁₄H₁₀O₈

• M _r = 306.22

• Monoclinic,

• a = 11.9983 (9) Å

• b = 8.2981 (6) Å

• c = 13.7634 (11) Å

• β = 105.994 (7)°

• V = 1317.28 (17) ų

• Z = 4

• Mo Kα radiation

• μ = 0.13 mm⁻¹

• T = 293 K

• 0.25 × 0.20 × 0.20 mm

Data collection  

• Oxford Diffraction Xcalibur Eos diffractometer

• 2848 measured reflections

• 1342 independent reflections

• 937 reflections with I > 2σ(I)

• R _int = 0.022

Refinement  

• R[F ² > 2σ(F ²)] = 0.044

• wR(F ²) = 0.118

• S = 1.06

• 1342 reflections

• 103 parameters

• H-atom parameters constrained

• Δρ_max = 0.21 e Å⁻³

• Δρ_min = −0.17 e Å⁻³

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 ▶); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2009 ▶); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536812012950/xu5486Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯O4i	0.82	2.03	2.770 (2)	150
O3—H3⋯O1ii	0.82	2.03	2.7658 (19)	150

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

The oosporein was previously isolated from Phlebia mellea (Takeshita & Anchel, 1965), and its structure was established from the spectroscopic data (Richard et al., 1974). In our recent investigation, it was isolated from Tremella fuciformis for the first time, and its structure is reported here.

The molecular structure of the title compound is shown in Fig. 1. The molecule of the title compound contains two plane six-membered rings which assumes a screw-plane conformation, and there is a dihedral angle between the two planes.

The crystal structure contains intermolecular O—H···O hydrogen bonding between the hydroxy group and the aldehyde atom (Table 1).

Experimental

Tremella fuciformis was a culture collection of our laboratory, the stock culture was maintained on potato dextrose agar (PDA) slants and subcultured once a month. It was used in submerged culture. Agar, slants containing potato–dextrose–agar were inoculated with mycelia and incubated at 25 °C for 5 days, and then used as inoculums for seed culture. The seed culture was grown in 250 ml shake flasks containing 50 ml for 2 days at initial pH 6.8–7.0, 25 °C, and 150 rpm with a medium containing 20 g.l^-1 glucose, 2 g.l^-1 soybean meal leaching solution, 1.0 g.l^-1 MgSO₄, 1.0 g.l^-1 KH₂PO₄ and 0.46 g.l^-1 K₂HPO₄. Submerged fermentation was the same as the seed culture medium. All media were sterilized at 115 °C for 20 min. Fermentation liquid centrifugal (10000 rpm) and then rotary evaporation at 50 °C. Fermented liquid was concentrated by rotating evaporation at 50°C and add 4 times the volume of the anhydrous alcohol, 4 °C for the night precipitation, 10000 rmp centrifugal remove polysaccharides and protein. Rotated evaporation and concentration, concentrate on D101 macroporous resin adsorption, first washed with distilled water, then elution with 95% ethanol elution, eluent was saved at 4°C, to obtain crud crystals, crud crystals washing was 95% ethanol, and then recrystallized in 95% ethanol solution.

Refinement

H atoms were located geometrically with O—H = 0.82 Å and C—H = 0.96 Å, and using a riding model with U_iso(H) = 1.5U_eq(C,O).

Figures

Fig. 1.

The molecular structure of the title compound with 30% probability displacement ellipsoids for non-H atoms.

Crystal data

C14H10O8	F(000) = 632
Mr = 306.22	Dx = 1.544 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.9983 (9) Å	Cell parameters from 884 reflections
b = 8.2981 (6) Å	θ = 3.0–28.7°
c = 13.7634 (11) Å	µ = 0.13 mm−1
β = 105.994 (7)°	T = 293 K
V = 1317.28 (17) Å3	Block, colorless
Z = 4	0.25 × 0.20 × 0.20 mm

Data collection

Oxford Diffraction Xcalibur Eos diffractometer	937 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.022
Graphite monochromator	θmax = 26.4°, θmin = 3.0°
Detector resolution: 10.0 pixels mm-1	h = −14→11
ω scans	k = −9→10
2848 measured reflections	l = −17→13
1342 independent reflections

Refinement

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118	H-atom parameters constrained
S = 1.06	w = 1/[σ2(Fo2) + (0.0491P)2 + 0.4579P] where P = (Fo2 + 2Fc2)/3
1342 reflections	(Δ/σ)max < 0.001
103 parameters	Δρmax = 0.21 e Å−3
0 restraints	Δρmin = −0.17 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	0.82546 (12)	0.06885 (18)	0.65807 (11)	0.0380 (4)
O2	0.79548 (13)	0.0605 (2)	0.45935 (11)	0.0434 (5)
H2	0.7623	0.0135	0.4958	0.065*
O3	1.16014 (12)	0.3820 (2)	0.71051 (11)	0.0402 (5)
H3	1.1965	0.4229	0.6744	0.060*
O4	1.12577 (13)	0.3814 (2)	0.51152 (12)	0.0454 (5)
C1	0.95888 (17)	0.2202 (2)	0.47435 (15)	0.0275 (5)
C2	0.88498 (16)	0.1437 (2)	0.51643 (15)	0.0274 (5)
C3	0.89706 (16)	0.1438 (2)	0.62776 (15)	0.0259 (5)
C4	0.99324 (15)	0.2298 (2)	0.69505 (14)	0.0232 (5)
C5	1.06929 (16)	0.3034 (2)	0.65361 (15)	0.0267 (5)
C6	1.05442 (17)	0.3056 (2)	0.54165 (16)	0.0284 (5)
C7	0.9473 (2)	0.2204 (3)	0.36334 (16)	0.0399 (6)
H7A	0.9064	0.1254	0.3332	0.060*
H7B	1.0229	0.2215	0.3525	0.060*
H7C	0.9050	0.3144	0.3331	0.060*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0323 (8)	0.0499 (10)	0.0336 (9)	−0.0172 (7)	0.0120 (7)	0.0003 (7)
O2	0.0398 (9)	0.0616 (12)	0.0274 (9)	−0.0259 (8)	0.0069 (7)	−0.0044 (8)
O3	0.0339 (9)	0.0544 (11)	0.0309 (9)	−0.0219 (7)	0.0066 (7)	−0.0014 (8)
O4	0.0416 (9)	0.0618 (11)	0.0351 (10)	−0.0259 (8)	0.0146 (7)	−0.0008 (8)
C1	0.0264 (10)	0.0320 (12)	0.0243 (11)	−0.0007 (9)	0.0074 (8)	−0.0006 (9)
C2	0.0236 (10)	0.0315 (12)	0.0259 (12)	−0.0045 (9)	0.0047 (8)	−0.0013 (9)
C3	0.0227 (10)	0.0269 (11)	0.0286 (12)	0.0003 (8)	0.0080 (8)	0.0034 (8)
C4	0.0223 (10)	0.0247 (11)	0.0227 (11)	0.0019 (8)	0.0064 (8)	0.0009 (8)
C5	0.0220 (10)	0.0289 (11)	0.0274 (12)	−0.0033 (8)	0.0040 (8)	−0.0019 (9)
C6	0.0260 (11)	0.0299 (12)	0.0313 (12)	−0.0024 (9)	0.0112 (9)	0.0018 (9)
C7	0.0424 (13)	0.0499 (15)	0.0291 (13)	−0.0063 (11)	0.0125 (10)	−0.0024 (11)

Geometric parameters (Å, º)

O1—C3	1.223 (2)	C2—C3	1.499 (3)
O2—C2	1.335 (2)	C3—C4	1.452 (3)
O2—H2	0.8200	C4—C5	1.348 (3)
O3—C5	1.325 (2)	C4—C4i	1.476 (4)
O3—H3	0.8200	C5—C6	1.502 (3)
O4—C6	1.223 (2)	C7—H7A	0.9600
C1—C2	1.344 (3)	C7—H7B	0.9600
C1—C6	1.445 (3)	C7—H7C	0.9600
C1—C7	1.496 (3)
C2—O2—H2	109.5	C3—C4—C4i	119.81 (18)
C5—O3—H3	109.5	O3—C5—C4	121.01 (18)
C2—C1—C6	117.14 (18)	O3—C5—C6	116.50 (17)
C2—C1—C7	123.62 (18)	C4—C5—C6	122.46 (17)
C6—C1—C7	119.24 (18)	O4—C6—C1	122.71 (19)
O2—C2—C1	120.65 (18)	O4—C6—C5	117.24 (18)
O2—C2—C3	115.94 (16)	C1—C6—C5	120.04 (17)
C1—C2—C3	123.41 (17)	C1—C7—H7A	109.5
O1—C3—C4	122.79 (19)	C1—C7—H7B	109.5
O1—C3—C2	117.97 (17)	H7A—C7—H7B	109.5
C4—C3—C2	119.23 (17)	C1—C7—H7C	109.5
C5—C4—C3	117.65 (18)	H7A—C7—H7C	109.5
C5—C4—C4i	122.51 (19)	H7B—C7—H7C	109.5

Symmetry code: (i) −x+2, y, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O4ii	0.82	2.03	2.770 (2)	150
O3—H3···O1iii	0.82	2.03	2.7658 (19)	150

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