Redetermination of 14-deoxy­andrographolide

The title compound [systematic name: ent-3β-hydr­oxy-8(17),13(14)-labdadiene-16,15-olide], C₂₀H₃₀O₄, contains two trans fused six-membered rings, with a lactone ring at the end of an equatorial side chain. The six-membered rings are in chair conformations and the lactone ring is planar. There is an infinite chain of both inter- and intra­molecular O—H...O hydrogen bonds along the b axis. The present study is a confirmation of the results of previous structure determinations of 14-deoxyandrographolide by Medforth, Chang, Chen, Olmstead & Smith [J. Chem. Soc. Perkin Trans. 2 (1990), pp. 1011--1016] and Rajnikant, Gupta, Singh, Lal, Gupta & Varghese [Mol. Cryst. Liq. Cryst. Sect. C (1996), 6, 227–233].

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.042
• wR factor = 0.112
• Data-to-parameter ratio = 9.9

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT707_ALERT_1_A D...A   Calc    6.409(3), Rep    2.675(2), Dev..    1244.67 Sigma
              O2   -O1      1.555   2.746
PLAT726_ALERT_1_A H...A   Calc     5.69000, Rep     1.98000 Dev...       3.71 Ang.
              H2#  -O1      1.555   2.746
PLAT728_ALERT_1_A D-H..A  Calc      150.00, Rep      142.00 Dev...       8.00 Deg.
              O2   -H2#  -O1      1.555   1.555   2.746

Alert level C
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          2

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           28.23
           From the CIF: _reflns_number_total               2189
           Count of symmetry unique reflns         2431
           Completeness (_total/calc)             90.05%
           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

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

   4 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

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Computing details

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1999); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1983).

Ent-3β-hydroxy-8(17),13 (14)-labdadiene-16,15-olide 14-deoxyandrographolide

Crystal data

C20H30O4	F(000) = 364
Mr = 334.44	Dx = 1.218 Mg m^−3
Monoclinic, P21	Melting point: 448 K
Hall symbol: P 2yb	Mo Kα radiation, λ = 0.71069 Å
a = 6.744 (2) Å	Cell parameters from 867 reflections
b = 6.988 (2) Å	θ = 5.2–23.6°
c = 19.377 (3) Å	µ = 0.08 mm^−1
β = 93.19 (3)°	T = 296 K
V = 911.8 (4) Å^3	Cylinder, colourless
Z = 2	0.23 × 0.22 × 0.11 mm

Data collection

Bruker AXS CCD diffractometer	2189 independent reflections
Radiation source: fine-focus sealed tube	1813 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.037
φ and ω scans	θmax = 28.2°, θmin = 2.1°
Absorption correction: multi-scan (SHELXTL-NT; Bruker, 1999)	h = −8→8
Tmin = 0.984, Tmax = 0.991	k = −9→9
9476 measured reflections	l = −25→25

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.112	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0663P)^2] where P = (Fo^2 + 2Fc^2)/3
2189 reflections	(Δ/σ)max = 0.001
222 parameters	Δρmax = 0.16 e Å^−3
1 restraint	Δρmin = −0.15 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
C1	0.6883 (4)	0.5357 (4)	0.25512 (12)	0.0623 (7)
H1A	0.5706	0.4590	0.2610	0.075*
H1B	0.7236	0.5220	0.2075	0.075*
C2	0.8563 (4)	0.4583 (4)	0.30206 (13)	0.0613 (6)
H2A	0.9766	0.5299	0.2948	0.074*
H2B	0.8801	0.3255	0.2906	0.074*
C3	0.8077 (4)	0.4730 (4)	0.37699 (12)	0.0526 (6)
H3	0.6865	0.3988	0.3831	0.063*
C4	0.7691 (3)	0.6805 (3)	0.39969 (10)	0.0432 (5)
C5	0.6117 (3)	0.7730 (3)	0.34805 (10)	0.0406 (5)
H5	0.4880	0.7054	0.3564	0.049*
C6	0.5670 (4)	0.9824 (4)	0.36349 (12)	0.0504 (5)
H6A	0.6783	1.0611	0.3513	0.061*
H6B	0.5505	0.9976	0.4126	0.061*
C7	0.3794 (4)	1.0502 (4)	0.32324 (15)	0.0625 (7)
H7A	0.2650	0.9908	0.3426	0.075*
H7B	0.3670	1.1875	0.3288	0.075*
C8	0.3776 (4)	1.0043 (4)	0.24724 (14)	0.0606 (7)
C9	0.4338 (3)	0.7991 (4)	0.23086 (12)	0.0541 (6)
H9	0.3349	0.7182	0.2518	0.065*
C10	0.6389 (3)	0.7461 (4)	0.26850 (10)	0.0446 (5)
C11	0.4189 (4)	0.7520 (6)	0.15320 (13)	0.0719 (9)
H11A	0.4763	0.8568	0.1282	0.086*
H11B	0.4975	0.6386	0.1454	0.086*
C12	0.2145 (3)	0.7190 (5)	0.12452 (11)	0.0605 (6)
H12A	0.1309	0.8210	0.1405	0.073*
H12B	0.1670	0.6001	0.1435	0.073*
C13	0.1878 (3)	0.7089 (4)	0.04827 (11)	0.0530 (6)
C14	0.3163 (4)	0.7087 (5)	−0.00097 (13)	0.0636 (7)
H14	0.4537	0.7101	0.0065	0.076*
C15	0.2087 (5)	0.7059 (7)	−0.06974 (14)	0.0831 (10)
H15A	0.2396	0.8188	−0.0962	0.100*
H15B	0.2431	0.5929	−0.0956	0.100*
C16	−0.0128 (4)	0.7050 (5)	0.01416 (14)	0.0637 (7)
C17	0.7979 (3)	0.8743 (4)	0.23930 (12)	0.0537 (6)
H17A	0.7982	0.8570	0.1902	0.081*
H17B	0.9257	0.8406	0.2601	0.081*
H17C	0.7696	1.0057	0.2494	0.081*
C18	0.6816 (4)	0.6731 (4)	0.47192 (11)	0.0556 (6)
H18A	0.7626	0.5920	0.5019	0.083*
H18B	0.5490	0.6230	0.4676	0.083*
H18C	0.6790	0.7998	0.4910	0.083*
C19	0.9647 (3)	0.7945 (4)	0.40506 (12)	0.0517 (6)
H19A	1.0243	0.7901	0.3607	0.062*
H19B	0.9345	0.9273	0.4146	0.062*
C20	0.3274 (5)	1.1371 (6)	0.2001 (2)	0.0901 (11)
H20A	0.2930	1.2595	0.2141	0.108*
H20B	0.3267	1.1074	0.1533	0.108*
O1	0.9667 (3)	0.3839 (3)	0.41743 (10)	0.0683 (5)
H1O1	0.9254	0.3458	0.4540	0.102*
O2	1.1061 (3)	0.7276 (3)	0.45678 (9)	0.0658 (5)
H2O2	1.1126	0.6106	0.4550	0.099*
O3	0.0022 (3)	0.7034 (5)	−0.05481 (10)	0.0857 (7)
O4	−0.1710 (3)	0.7026 (5)	0.04002 (12)	0.0880 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0824 (18)	0.0661 (16)	0.0377 (12)	−0.0109 (14)	−0.0021 (11)	−0.0122 (11)
C2	0.0815 (17)	0.0527 (14)	0.0499 (14)	0.0045 (13)	0.0042 (12)	−0.0115 (11)
C3	0.0608 (13)	0.0493 (13)	0.0471 (13)	−0.0028 (11)	−0.0015 (10)	0.0003 (10)
C4	0.0496 (11)	0.0486 (12)	0.0312 (9)	−0.0085 (9)	0.0022 (8)	0.0003 (9)
C5	0.0406 (10)	0.0489 (12)	0.0324 (10)	−0.0110 (8)	0.0020 (8)	0.0010 (8)
C6	0.0537 (12)	0.0559 (15)	0.0419 (12)	−0.0028 (11)	0.0052 (9)	−0.0011 (10)
C7	0.0503 (13)	0.0643 (16)	0.0731 (17)	0.0027 (12)	0.0062 (11)	0.0073 (13)
C8	0.0421 (12)	0.0763 (18)	0.0621 (15)	−0.0121 (11)	−0.0097 (10)	0.0167 (13)
C9	0.0447 (12)	0.0747 (17)	0.0420 (12)	−0.0165 (11)	−0.0062 (9)	0.0091 (11)
C10	0.0470 (11)	0.0557 (13)	0.0304 (10)	−0.0129 (10)	−0.0038 (8)	0.0019 (9)
C11	0.0571 (14)	0.115 (3)	0.0422 (13)	−0.0200 (16)	−0.0120 (10)	0.0135 (15)
C12	0.0506 (12)	0.0868 (19)	0.0439 (12)	−0.0131 (14)	0.0006 (9)	−0.0029 (14)
C13	0.0479 (11)	0.0649 (15)	0.0454 (11)	−0.0045 (12)	−0.0043 (9)	−0.0082 (12)
C14	0.0566 (13)	0.0855 (18)	0.0483 (12)	0.0010 (14)	−0.0017 (10)	−0.0091 (14)
C15	0.081 (2)	0.120 (3)	0.0477 (14)	0.004 (2)	−0.0019 (13)	−0.0142 (18)
C16	0.0553 (14)	0.0728 (17)	0.0611 (15)	0.0026 (13)	−0.0134 (12)	−0.0119 (14)
C17	0.0483 (12)	0.0742 (16)	0.0385 (11)	−0.0127 (11)	0.0021 (9)	0.0081 (11)
C18	0.0608 (13)	0.0719 (17)	0.0341 (10)	−0.0018 (12)	0.0032 (9)	0.0036 (11)
C19	0.0483 (12)	0.0618 (14)	0.0440 (12)	−0.0110 (10)	−0.0050 (9)	−0.0028 (10)
C20	0.090 (2)	0.083 (2)	0.092 (2)	−0.0213 (18)	−0.0364 (18)	0.0278 (17)
O1	0.0780 (13)	0.0648 (12)	0.0611 (11)	0.0134 (10)	−0.0043 (9)	0.0078 (9)
O2	0.0570 (9)	0.0810 (13)	0.0574 (10)	−0.0023 (10)	−0.0147 (7)	−0.0096 (10)
O3	0.0741 (13)	0.1245 (19)	0.0557 (11)	0.0026 (14)	−0.0230 (9)	−0.0149 (13)
O4	0.0488 (10)	0.1260 (19)	0.0880 (14)	−0.0064 (13)	−0.0057 (10)	−0.0171 (15)

Geometric parameters (Å, º)

C1—C2	1.513 (4)	C11—C12	1.475 (3)
C1—C10	1.533 (4)	C11—H11A	0.9700
C1—H1A	0.9700	C11—H11B	0.9700
C1—H1B	0.9700	C12—C13	1.480 (3)
C2—C3	1.510 (3)	C12—H12A	0.9700
C2—H2A	0.9700	C12—H12B	0.9700
C2—H2B	0.9700	C13—C14	1.324 (3)
C3—O1	1.435 (3)	C13—C16	1.473 (3)
C3—C4	1.542 (3)	C14—C15	1.482 (4)
C3—H3	0.9800	C14—H14	0.9300
C4—C19	1.540 (3)	C15—O3	1.438 (4)
C4—C18	1.550 (3)	C15—H15A	0.9700
C4—C5	1.558 (3)	C15—H15B	0.9700
C5—C6	1.527 (3)	C16—O4	1.204 (3)
C5—C10	1.574 (3)	C16—O3	1.346 (3)
C5—H5	0.9800	C17—H17A	0.9600
C6—C7	1.524 (4)	C17—H17B	0.9600
C6—H6A	0.9700	C17—H17C	0.9600
C6—H6B	0.9700	C18—H18A	0.9600
C7—C8	1.506 (4)	C18—H18B	0.9600
C7—H7A	0.9700	C18—H18C	0.9600
C7—H7B	0.9700	C19—O2	1.424 (3)
C8—C20	1.332 (4)	C19—H19A	0.9700
C8—C9	1.521 (4)	C19—H19B	0.9700
C9—C11	1.538 (3)	C20—H20A	0.9300
C9—C10	1.571 (3)	C20—H20B	0.9300
C9—H9	0.9800	O1—H1O1	0.8200
C10—C17	1.530 (3)	O2—H2O2	0.8200
C2—C1—C10	113.8 (2)	C17—C10—C5	114.48 (18)
C2—C1—H1A	108.8	C1—C10—C5	108.57 (18)
C10—C1—H1A	108.8	C9—C10—C5	106.21 (17)
C2—C1—H1B	108.8	C12—C11—C9	114.2 (2)
C10—C1—H1B	108.8	C12—C11—H11A	108.7
H1A—C1—H1B	107.7	C9—C11—H11A	108.7
C1—C2—C3	111.0 (2)	C12—C11—H11B	108.7
C1—C2—H2A	109.4	C9—C11—H11B	108.7
C3—C2—H2A	109.4	H11A—C11—H11B	107.6
C1—C2—H2B	109.4	C11—C12—C13	116.3 (2)
C3—C2—H2B	109.4	C11—C12—H12A	108.2
H2A—C2—H2B	108.0	C13—C12—H12A	108.2
O1—C3—C2	107.5 (2)	C11—C12—H12B	108.2
O1—C3—C4	112.7 (2)	C13—C12—H12B	108.2
C2—C3—C4	112.8 (2)	H12A—C12—H12B	107.4
O1—C3—H3	107.9	C14—C13—C16	107.3 (2)
C2—C3—H3	107.9	C14—C13—C12	132.2 (2)
C4—C3—H3	107.9	C16—C13—C12	120.4 (2)
C19—C4—C3	110.4 (2)	C13—C14—C15	109.9 (2)
C19—C4—C18	108.92 (18)	C13—C14—H14	125.0
C3—C4—C18	107.75 (18)	C15—C14—H14	125.0
C19—C4—C5	112.29 (18)	O3—C15—C14	104.5 (2)
C3—C4—C5	109.06 (18)	O3—C15—H15A	110.9
C18—C4—C5	108.30 (17)	C14—C15—H15A	110.9
C6—C5—C4	113.99 (18)	O3—C15—H15B	110.9
C6—C5—C10	109.96 (17)	C14—C15—H15B	110.9
C4—C5—C10	117.87 (17)	H15A—C15—H15B	108.9
C6—C5—H5	104.5	O4—C16—O3	122.0 (2)
C4—C5—H5	104.5	O4—C16—C13	128.8 (2)
C10—C5—H5	104.5	O3—C16—C13	109.2 (2)
C5—C6—C7	111.4 (2)	C10—C17—H17A	109.5
C5—C6—H6A	109.3	C10—C17—H17B	109.5
C7—C6—H6A	109.3	H17A—C17—H17B	109.5
C5—C6—H6B	109.3	C10—C17—H17C	109.5
C7—C6—H6B	109.3	H17A—C17—H17C	109.5
H6A—C6—H6B	108.0	H17B—C17—H17C	109.5
C8—C7—C6	113.3 (2)	C4—C18—H18A	109.5
C8—C7—H7A	108.9	C4—C18—H18B	109.5
C6—C7—H7A	108.9	H18A—C18—H18B	109.5
C8—C7—H7B	108.9	C4—C18—H18C	109.5
C6—C7—H7B	108.9	H18A—C18—H18C	109.5
H7A—C7—H7B	107.7	H18B—C18—H18C	109.5
C20—C8—C7	120.6 (3)	O2—C19—C4	114.6 (2)
C20—C8—C9	124.8 (3)	O2—C19—H19A	108.6
C7—C8—C9	114.6 (2)	C4—C19—H19A	108.6
C8—C9—C11	113.7 (2)	O2—C19—H19B	108.6
C8—C9—C10	110.4 (2)	C4—C19—H19B	108.6
C11—C9—C10	114.3 (2)	H19A—C19—H19B	107.6
C8—C9—H9	105.9	C8—C20—H20A	120.0
C11—C9—H9	105.9	C8—C20—H20B	120.0
C10—C9—H9	105.9	H20A—C20—H20B	120.0
C17—C10—C1	109.6 (2)	C3—O1—H1O1	109.5
C17—C10—C9	107.90 (18)	C19—O2—H2O2	109.5
C1—C10—C9	109.99 (19)	C16—O3—C15	109.07 (19)
C10—C1—C2—C3	59.5 (3)	C8—C9—C10—C1	176.70 (19)
C1—C2—C3—O1	175.7 (2)	C11—C9—C10—C1	−53.6 (3)
C1—C2—C3—C4	−59.5 (3)	C8—C9—C10—C5	59.4 (2)
O1—C3—C4—C19	49.8 (3)	C11—C9—C10—C5	−170.9 (2)
C2—C3—C4—C19	−72.1 (3)	C6—C5—C10—C17	55.9 (3)
O1—C3—C4—C18	−69.0 (2)	C4—C5—C10—C17	−77.1 (3)
C2—C3—C4—C18	169.10 (19)	C6—C5—C10—C1	178.67 (19)
O1—C3—C4—C5	173.63 (18)	C4—C5—C10—C1	45.7 (2)
C2—C3—C4—C5	51.7 (2)	C6—C5—C10—C9	−63.1 (2)
C19—C4—C5—C6	−55.0 (2)	C4—C5—C10—C9	163.98 (19)
C3—C4—C5—C6	−177.64 (18)	C8—C9—C11—C12	−77.7 (3)
C18—C4—C5—C6	65.4 (2)	C10—C9—C11—C12	154.3 (3)
C19—C4—C5—C10	76.2 (2)	C9—C11—C12—C13	169.0 (3)
C3—C4—C5—C10	−46.5 (2)	C11—C12—C13—C14	6.3 (5)
C18—C4—C5—C10	−163.51 (18)	C11—C12—C13—C16	−170.9 (3)
C4—C5—C6—C7	−166.06 (18)	C16—C13—C14—C15	0.4 (4)
C10—C5—C6—C7	59.0 (2)	C12—C13—C14—C15	−177.1 (4)
C5—C6—C7—C8	−50.1 (3)	C13—C14—C15—O3	−0.3 (4)
C6—C7—C8—C20	−132.9 (3)	C14—C13—C16—O4	179.4 (4)
C6—C7—C8—C9	47.9 (3)	C12—C13—C16—O4	−2.7 (5)
C20—C8—C9—C11	−2.7 (4)	C14—C13—C16—O3	−0.2 (4)
C7—C8—C9—C11	176.53 (18)	C12—C13—C16—O3	177.6 (3)
C20—C8—C9—C10	127.3 (3)	C3—C4—C19—O2	−64.3 (3)
C7—C8—C9—C10	−53.5 (2)	C18—C4—C19—O2	53.8 (3)
C2—C1—C10—C17	75.2 (3)	C5—C4—C19—O2	173.78 (19)
C2—C1—C10—C9	−166.4 (2)	O4—C16—O3—C15	−179.7 (3)
C2—C1—C10—C5	−50.5 (3)	C13—C16—O3—C15	0.0 (4)
C8—C9—C10—C17	−63.8 (2)	C14—C15—O3—C16	0.2 (4)
C11—C9—C10—C17	65.9 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O2···O1^i	0.82	1.98	2.675 (2)	142
O1—H1O1···O2^i	0.82	1.94	2.740 (2)	166

Symmetry code: (i) −x+2, y−1/2, −z+1.