16α,17-Epoxy­pregn-4-ene-3,11,20-trione

The title compound, C₂₁H₂₆O₄, is an important steroid used as an intermediate in the synthesis of hormone pharmaceuticals. No inter- or intramolecular hydrogen bonds were observed in the crystal structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.040
• wR factor = 0.109
• Data-to-parameter ratio = 10.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.96
           From the CIF: _reflns_number_total               2396
           Count of symmetry unique reflns         2398
           Completeness (_total/calc)             99.92%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present           no

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   2 ALERT type 4 Improvement, methodology, query or suggestion

---

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.

17-acetyl-10,13-dimethyl-1,2,6,7,9,10,12,13,14,15,16, 17-dodecahydro-8H-20-oxa-cyclopropa[16,17]cyclopenta[a]phenanthrene-3,11-dione

Crystal data

C21H26O4	Dx = 1.309 Mg m^−3
Mr = 342.42	Melting point: 465.5 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
a = 7.5364 (12) Å	Cell parameters from 2892 reflections
b = 9.9000 (16) Å	θ = 2.2–23.9°
c = 23.288 (4) Å	µ = 0.09 mm^−1
V = 1737.6 (5) Å^3	T = 293 K
Z = 4	Prism, colourless
F(000) = 736	0.32 × 0.28 × 0.24 mm

Data collection

Bruker SMART CCD area-detector diffractometer	1925 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.042
Graphite monochromator	θmax = 28.0°, θmin = 1.8°
φ and ω scans	h = −9→9
11707 measured reflections	k = −12→13
2396 independent reflections	l = −30→18

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.109	H-atom parameters constrained
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0616P)^2 + 0.0814P] where P = (Fo^2 + 2Fc^2)/3
2396 reflections	(Δ/σ)max = 0.001
229 parameters	Δρmax = 0.22 e Å^−3
0 restraints	Δρmin = −0.16 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	0.8985 (3)	0.1964 (2)	1.24390 (8)	0.0832 (7)
O2	1.1689 (2)	−0.11303 (18)	1.00984 (6)	0.0561 (5)
O3	0.8436 (2)	0.19701 (15)	0.83762 (6)	0.0489 (4)
O4	1.1264 (3)	−0.0667 (2)	0.79259 (8)	0.0846 (7)
C1	1.0674 (3)	0.0304 (2)	1.11767 (9)	0.0413 (5)
H1A	1.1620	−0.0327	1.1089	0.050*
H1B	1.1011	0.1177	1.1022	0.050*
C2	1.0505 (3)	0.0423 (3)	1.18261 (9)	0.0500 (6)
H2A	1.0333	−0.0469	1.1989	0.060*
H2B	1.1597	0.0790	1.1982	0.060*
C3	0.8996 (3)	0.1306 (3)	1.19948 (9)	0.0513 (6)
C4	0.7451 (3)	0.1285 (2)	1.16125 (9)	0.0474 (5)
H4	0.6469	0.1800	1.1715	0.057*
C5	0.7367 (3)	0.0568 (2)	1.11240 (9)	0.0377 (5)
C6	0.5647 (3)	0.0424 (3)	1.08109 (9)	0.0460 (5)
H6A	0.4768	0.1004	1.0989	0.055*
H6B	0.5236	−0.0502	1.0845	0.055*
C7	0.5804 (3)	0.0786 (2)	1.01806 (9)	0.0433 (5)
H7A	0.6007	0.1750	1.0145	0.052*
H7B	0.4695	0.0576	0.9989	0.052*
C8	0.7305 (2)	0.0031 (2)	0.98850 (8)	0.0348 (4)
H8	0.7020	−0.0933	0.9864	0.042*
C9	0.9059 (2)	0.02354 (19)	1.02278 (8)	0.0332 (4)
H9	0.9245	0.1215	1.0231	0.040*
C10	0.8966 (3)	−0.0170 (2)	1.08735 (8)	0.0348 (4)
C11	1.0654 (3)	−0.0330 (2)	0.98977 (9)	0.0378 (4)
C12	1.0861 (3)	0.0166 (2)	0.92849 (8)	0.0408 (5)
H12A	1.1834	−0.0306	0.9100	0.049*
H12B	1.1127	0.1124	0.9284	0.049*
C13	0.9140 (3)	−0.0093 (2)	0.89569 (8)	0.0367 (4)
C14	0.7605 (3)	0.0587 (2)	0.92816 (8)	0.0367 (4)
H14	0.7974	0.1527	0.9336	0.044*
C15	0.6092 (3)	0.0637 (2)	0.88410 (9)	0.0456 (5)
H15A	0.5482	−0.0223	0.8815	0.055*
H15B	0.5242	0.1340	0.8933	0.055*
C16	0.7091 (3)	0.0954 (2)	0.82950 (9)	0.0490 (6)
H16	0.6506	0.0856	0.7922	0.059*
C17	0.8970 (3)	0.0552 (2)	0.83655 (9)	0.0413 (5)
C18	1.0193 (4)	0.0232 (3)	0.78775 (10)	0.0527 (6)
C19	1.0096 (4)	0.1083 (3)	0.73467 (9)	0.0619 (7)
H19A	1.0913	0.1823	0.7379	0.093*
H19B	0.8913	0.1427	0.7302	0.093*
H19C	1.0401	0.0544	0.7018	0.093*
C20	0.8700 (3)	−0.1701 (2)	1.09535 (10)	0.0466 (5)
H20A	0.9711	−0.2174	1.0804	0.070*
H20B	0.7653	−0.1982	1.0752	0.070*
H20C	0.8572	−0.1900	1.1355	0.070*
C21	0.8842 (3)	−0.1623 (2)	0.88832 (9)	0.0445 (5)
H21A	0.7789	−0.1773	0.8660	0.067*
H21B	0.8708	−0.2035	0.9254	0.067*
H21C	0.9843	−0.2013	0.8690	0.067*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0832 (14)	0.1089 (16)	0.0575 (11)	0.0113 (15)	−0.0044 (11)	−0.0357 (11)
O2	0.0456 (9)	0.0693 (11)	0.0535 (9)	0.0265 (8)	0.0035 (7)	0.0028 (8)
O3	0.0606 (10)	0.0361 (7)	0.0501 (9)	0.0009 (8)	−0.0037 (8)	0.0039 (6)
O4	0.1016 (16)	0.0794 (13)	0.0727 (12)	0.0310 (14)	0.0402 (12)	0.0181 (10)
C1	0.0357 (10)	0.0444 (11)	0.0438 (11)	0.0006 (10)	0.0022 (9)	−0.0007 (9)
C2	0.0468 (12)	0.0575 (13)	0.0457 (12)	0.0000 (12)	−0.0050 (10)	−0.0005 (10)
C3	0.0552 (14)	0.0559 (13)	0.0428 (11)	−0.0054 (13)	0.0042 (11)	−0.0046 (10)
C4	0.0465 (12)	0.0459 (12)	0.0498 (12)	0.0061 (11)	0.0094 (10)	−0.0049 (10)
C5	0.0346 (10)	0.0363 (10)	0.0420 (11)	−0.0016 (9)	0.0082 (8)	0.0016 (8)
C6	0.0311 (10)	0.0541 (13)	0.0528 (12)	0.0022 (11)	0.0102 (9)	−0.0070 (10)
C7	0.0288 (10)	0.0508 (12)	0.0503 (12)	0.0057 (9)	0.0024 (9)	−0.0050 (10)
C8	0.0279 (9)	0.0332 (9)	0.0431 (10)	−0.0008 (8)	0.0022 (8)	−0.0030 (8)
C9	0.0278 (9)	0.0313 (9)	0.0405 (10)	0.0004 (8)	0.0027 (8)	−0.0022 (8)
C10	0.0308 (9)	0.0343 (10)	0.0394 (10)	−0.0012 (9)	0.0048 (8)	0.0004 (8)
C11	0.0296 (9)	0.0399 (10)	0.0440 (11)	0.0021 (9)	0.0008 (8)	−0.0035 (9)
C12	0.0341 (10)	0.0456 (12)	0.0427 (11)	0.0019 (10)	0.0064 (9)	−0.0006 (9)
C13	0.0375 (11)	0.0333 (10)	0.0393 (10)	0.0004 (9)	0.0032 (9)	−0.0014 (8)
C14	0.0358 (10)	0.0334 (10)	0.0407 (10)	0.0008 (9)	−0.0002 (8)	−0.0019 (8)
C15	0.0397 (11)	0.0432 (12)	0.0540 (13)	0.0025 (10)	−0.0062 (10)	−0.0034 (10)
C16	0.0561 (13)	0.0475 (12)	0.0435 (12)	0.0005 (11)	−0.0096 (10)	−0.0013 (10)
C17	0.0504 (12)	0.0338 (10)	0.0398 (10)	−0.0029 (10)	−0.0010 (10)	−0.0008 (8)
C18	0.0648 (15)	0.0470 (13)	0.0463 (12)	−0.0068 (13)	0.0080 (12)	−0.0024 (10)
C19	0.0787 (18)	0.0682 (16)	0.0387 (13)	−0.0106 (16)	−0.0004 (13)	−0.0009 (11)
C20	0.0497 (12)	0.0376 (11)	0.0524 (12)	−0.0016 (11)	0.0039 (11)	0.0031 (9)
C21	0.0497 (13)	0.0366 (10)	0.0471 (12)	−0.0002 (10)	0.0035 (10)	−0.0017 (9)

Geometric parameters (Å, º)

O1—C3	1.223 (3)	C9—H9	0.9800
O2—C11	1.206 (2)	C10—C20	1.540 (3)
O3—C16	1.440 (3)	C11—C12	1.517 (3)
O3—C17	1.461 (3)	C12—C13	1.526 (3)
O4—C18	1.207 (3)	C12—H12A	0.9700
C1—C2	1.522 (3)	C12—H12B	0.9700
C1—C10	1.541 (3)	C13—C17	1.524 (3)
C1—H1A	0.9700	C13—C14	1.538 (3)
C1—H1B	0.9700	C13—C21	1.541 (3)
C2—C3	1.487 (3)	C14—C15	1.535 (3)
C2—H2A	0.9700	C14—H14	0.9800
C2—H2B	0.9700	C15—C16	1.511 (3)
C3—C4	1.466 (3)	C15—H15A	0.9700
C4—C5	1.342 (3)	C15—H15B	0.9700
C4—H4	0.9300	C16—C17	1.480 (3)
C5—C6	1.494 (3)	C16—H16	0.9800
C5—C10	1.525 (3)	C17—C18	1.497 (3)
C6—C7	1.516 (3)	C18—C19	1.498 (3)
C6—H6A	0.9700	C19—H19A	0.9600
C6—H6B	0.9700	C19—H19B	0.9600
C7—C8	1.520 (3)	C19—H19C	0.9600
C7—H7A	0.9700	C20—H20A	0.9600
C7—H7B	0.9700	C20—H20B	0.9600
C8—C14	1.526 (3)	C20—H20C	0.9600
C8—C9	1.557 (3)	C21—H21A	0.9600
C8—H8	0.9800	C21—H21B	0.9600
C9—C11	1.533 (3)	C21—H21C	0.9600
C9—C10	1.558 (3)
C16—O3—C17	61.36 (15)	C11—C12—H12A	109.8
C2—C1—C10	114.13 (18)	C13—C12—H12A	109.8
C2—C1—H1A	108.7	C11—C12—H12B	109.8
C10—C1—H1A	108.7	C13—C12—H12B	109.8
C2—C1—H1B	108.7	H12A—C12—H12B	108.3
C10—C1—H1B	108.7	C17—C13—C12	116.97 (18)
H1A—C1—H1B	107.6	C17—C13—C14	101.39 (16)
C3—C2—C1	111.83 (19)	C12—C13—C14	108.64 (15)
C3—C2—H2A	109.3	C17—C13—C21	107.41 (16)
C1—C2—H2A	109.3	C12—C13—C21	110.18 (18)
C3—C2—H2B	109.3	C14—C13—C21	112.04 (18)
C1—C2—H2B	109.3	C8—C14—C15	121.18 (17)
H2A—C2—H2B	107.9	C8—C14—C13	113.98 (16)
O1—C3—C4	121.1 (2)	C15—C14—C13	104.15 (15)
O1—C3—C2	122.8 (2)	C8—C14—H14	105.4
C4—C3—C2	116.01 (18)	C15—C14—H14	105.4
C5—C4—C3	124.0 (2)	C13—C14—H14	105.4
C5—C4—H4	118.0	C16—C15—C14	101.50 (17)
C3—C4—H4	118.0	C16—C15—H15A	111.5
C4—C5—C6	120.35 (19)	C14—C15—H15A	111.5
C4—C5—C10	122.69 (19)	C16—C15—H15B	111.5
C6—C5—C10	116.93 (16)	C14—C15—H15B	111.5
C5—C6—C7	112.47 (17)	H15A—C15—H15B	109.3
C5—C6—H6A	109.1	O3—C16—C17	60.00 (14)
C7—C6—H6A	109.1	O3—C16—C15	112.67 (17)
C5—C6—H6B	109.1	C17—C16—C15	109.12 (18)
C7—C6—H6B	109.1	O3—C16—H16	120.1
H6A—C6—H6B	107.8	C17—C16—H16	120.1
C6—C7—C8	112.36 (18)	C15—C16—H16	120.1
C6—C7—H7A	109.1	O3—C17—C16	58.64 (14)
C8—C7—H7A	109.1	O3—C17—C18	112.73 (18)
C6—C7—H7B	109.1	C16—C17—C18	124.2 (2)
C8—C7—H7B	109.1	O3—C17—C13	114.25 (16)
H7A—C7—H7B	107.9	C16—C17—C13	107.07 (18)
C7—C8—C14	110.48 (17)	C18—C17—C13	123.1 (2)
C7—C8—C9	109.62 (15)	O4—C18—C17	119.8 (2)
C14—C8—C9	107.45 (15)	O4—C18—C19	121.6 (2)
C7—C8—H8	109.8	C17—C18—C19	118.5 (2)
C14—C8—H8	109.8	C18—C19—H19A	109.5
C9—C8—H8	109.8	C18—C19—H19B	109.5
C11—C9—C8	111.17 (14)	H19A—C19—H19B	109.5
C11—C9—C10	115.17 (16)	C18—C19—H19C	109.5
C8—C9—C10	115.03 (15)	H19A—C19—H19C	109.5
C11—C9—H9	104.7	H19B—C19—H19C	109.5
C8—C9—H9	104.7	C10—C20—H20A	109.5
C10—C9—H9	104.7	C10—C20—H20B	109.5
C5—C10—C20	108.82 (17)	H20A—C20—H20B	109.5
C5—C10—C1	109.79 (15)	C10—C20—H20C	109.5
C20—C10—C1	110.67 (19)	H20A—C20—H20C	109.5
C5—C10—C9	106.35 (16)	H20B—C20—H20C	109.5
C20—C10—C9	112.09 (17)	C13—C21—H21A	109.5
C1—C10—C9	109.03 (15)	C13—C21—H21B	109.5
O2—C11—C12	120.71 (19)	H21A—C21—H21B	109.5
O2—C11—C9	123.57 (19)	C13—C21—H21C	109.5
C12—C11—C9	115.71 (17)	H21A—C21—H21C	109.5
C11—C12—C13	109.22 (17)	H21B—C21—H21C	109.5
C10—C1—C2—C3	−54.6 (3)	C11—C12—C13—C21	−67.3 (2)
C1—C2—C3—O1	−150.8 (2)	C7—C8—C14—C15	−56.1 (2)
C1—C2—C3—C4	32.8 (3)	C9—C8—C14—C15	−175.64 (17)
O1—C3—C4—C5	−178.9 (2)	C7—C8—C14—C13	178.33 (16)
C2—C3—C4—C5	−2.4 (3)	C9—C8—C14—C13	58.8 (2)
C3—C4—C5—C6	169.9 (2)	C17—C13—C14—C8	174.08 (16)
C3—C4—C5—C10	−7.9 (3)	C12—C13—C14—C8	−62.1 (2)
C4—C5—C6—C7	128.7 (2)	C21—C13—C14—C8	59.8 (2)
C10—C5—C6—C7	−53.3 (3)	C17—C13—C14—C15	39.9 (2)
C5—C6—C7—C8	52.3 (3)	C12—C13—C14—C15	163.72 (17)
C6—C7—C8—C14	−171.00 (17)	C21—C13—C14—C15	−74.3 (2)
C6—C7—C8—C9	−52.8 (2)	C8—C14—C15—C16	−168.18 (18)
C7—C8—C9—C11	−171.54 (17)	C13—C14—C15—C16	−38.2 (2)
C14—C8—C9—C11	−51.4 (2)	C17—O3—C16—C15	99.7 (2)
C7—C8—C9—C10	55.3 (2)	C14—C15—C16—O3	−42.7 (2)
C14—C8—C9—C10	175.38 (16)	C14—C15—C16—C17	21.9 (2)
C4—C5—C10—C20	108.3 (2)	C16—O3—C17—C18	117.3 (2)
C6—C5—C10—C20	−69.6 (2)	C16—O3—C17—C13	−95.9 (2)
C4—C5—C10—C1	−13.0 (3)	C15—C16—C17—O3	−105.72 (19)
C6—C5—C10—C1	169.12 (19)	O3—C16—C17—C18	−97.6 (2)
C4—C5—C10—C9	−130.8 (2)	C15—C16—C17—C18	156.6 (2)
C6—C5—C10—C9	51.3 (2)	O3—C16—C17—C13	108.42 (17)
C2—C1—C10—C5	43.6 (2)	C15—C16—C17—C13	2.7 (2)
C2—C1—C10—C20	−76.5 (2)	C12—C13—C17—O3	−81.4 (2)
C2—C1—C10—C9	159.77 (18)	C14—C13—C17—O3	36.6 (2)
C11—C9—C10—C5	176.39 (16)	C21—C13—C17—O3	154.24 (19)
C8—C9—C10—C5	−52.3 (2)	C12—C13—C17—C16	−144.05 (19)
C11—C9—C10—C20	−64.8 (2)	C14—C13—C17—C16	−26.1 (2)
C8—C9—C10—C20	66.5 (2)	C21—C13—C17—C16	91.5 (2)
C11—C9—C10—C1	58.1 (2)	C12—C13—C17—C18	61.7 (3)
C8—C9—C10—C1	−170.64 (16)	C14—C13—C17—C18	179.58 (19)
C8—C9—C11—O2	−126.6 (2)	C21—C13—C17—C18	−62.7 (3)
C10—C9—C11—O2	6.5 (3)	O3—C17—C18—O4	150.9 (2)
C8—C9—C11—C12	52.6 (2)	C16—C17—C18—O4	−142.5 (3)
C10—C9—C11—C12	−174.26 (17)	C13—C17—C18—O4	7.4 (4)
O2—C11—C12—C13	124.9 (2)	O3—C17—C18—C19	−26.6 (3)
C9—C11—C12—C13	−54.3 (2)	C16—C17—C18—C19	39.9 (3)
C11—C12—C13—C17	169.69 (17)	C13—C17—C18—C19	−170.2 (2)
C11—C12—C13—C14	55.8 (2)