Raucaffrinoline

In the crystal structure of the title compound [systematic name: (17R,20α,21β)-1,2-didehydro-1-demethyl-19-hydr­oxy-21-methyl-18-norajmalan-17-yl acetate], C₂₁H₂₄N₂O₃, an inter­molecular O—H...O hydrogen bond [2.810 (4) Å and 160°] stabilizes the mol­ecular packing as an infinite chain along the [100] direction.

Key indicators

• Single-crystal X-ray study
• T = 297 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.040
• wR factor = 0.107
• Data-to-parameter ratio = 7.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.95

Alert level C
REFLT03_ALERT_1_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           67.96
           From the CIF: _diffrn_reflns_theta_full          67.96
           From the CIF: _reflns_number_total               1788
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         1883
           Completeness (_total/calc)             94.95%
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       7.58
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          5

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           67.96
           From the CIF: _reflns_number_total               1788
           Count of symmetry unique reflns         1883
           Completeness (_total/calc)             94.95%
           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
   1 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

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

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1994); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

(17R,20α,21β)-1,2-didehydro-1-demethyl-19-hydroxy-21-methyl-18- norajmalan-17-yl acetate

Crystal data

C21H24N2O3	Dx = 1.307 Mg m^−3
Mr = 352.42	Melting point: 350.0 K
Orthorhombic, P212121	Cu Kα radiation, λ = 1.54180 Å
Hall symbol: P 2ac 2ab	Cell parameters from 25 reflections
a = 9.436 (1) Å	θ = 16.2–31.5°
b = 10.588 (1) Å	µ = 0.71 mm^−1
c = 17.926 (2) Å	T = 297 K
V = 1791.0 (3) Å^3	Block, brown
Z = 4	0.18 × 0.15 × 0.08 mm
F(000) = 752

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.072
Radiation source: fine-focus sealed tube	θmax = 68.0°, θmin = 4.9°
Graphite monochromator	h = 0→11
non–profiled ω/2θ scans	k = 0→12
3454 measured reflections	l = −21→21
1788 independent reflections	2 standard reflections every 120 min
1135 reflections with I > 2σ(I)	intensity decay: 3%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.040	H-atom parameters constrained
wR(F^2) = 0.107	w = 1/[σ^2(Fo^2) + (0.053P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max < 0.001
1788 reflections	Δρmax = 0.19 e Å^−3
236 parameters	Δρmin = −0.19 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0016 (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.

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

	x	y	z	Uiso*/Ueq
O1	0.5945 (3)	0.8196 (4)	1.05637 (16)	0.0884 (13)
H1	0.6133	0.7941	1.0984	0.106*
O2	0.3632 (2)	0.8395 (3)	0.72259 (13)	0.0407 (7)
O3	0.2291 (3)	0.7512 (4)	0.81018 (18)	0.0704 (10)
N1	0.7825 (3)	0.6357 (3)	0.68044 (19)	0.0495 (9)
N2	0.8024 (3)	0.8839 (3)	0.81277 (17)	0.0404 (8)
C1	0.5852 (4)	0.7323 (4)	0.6242 (2)	0.0433 (10)
C2	0.4896 (5)	0.7503 (4)	0.5676 (2)	0.0514 (11)
H2	0.4184	0.8105	0.5723	0.062*
C3	0.5000 (6)	0.6779 (4)	0.5030 (2)	0.0580 (12)
H3	0.4368	0.6910	0.4639	0.070*
C4	0.6041 (6)	0.5866 (5)	0.4970 (2)	0.0637 (13)
H4	0.6080	0.5367	0.4543	0.076*
C5	0.7025 (5)	0.5677 (4)	0.5529 (2)	0.0589 (12)
H5	0.7734	0.5074	0.5480	0.071*
C6	0.6925 (5)	0.6411 (4)	0.6163 (2)	0.0460 (10)
C7	0.7341 (4)	0.7176 (4)	0.7265 (2)	0.0400 (10)
C8	0.6061 (4)	0.7901 (4)	0.69927 (19)	0.0382 (9)
C9	0.6499 (4)	0.9307 (4)	0.7057 (2)	0.0417 (10)
H9A	0.7379	0.9477	0.6796	0.050*
H9B	0.5764	0.9867	0.6873	0.050*
C10	0.6674 (4)	0.9408 (4)	0.7896 (2)	0.0409 (9)
H10	0.6626	1.0292	0.8054	0.049*
C11	0.5411 (4)	0.8646 (4)	0.82272 (19)	0.0390 (9)
H11	0.4664	0.9225	0.8392	0.047*
C12	0.4878 (4)	0.7842 (3)	0.75733 (19)	0.0357 (9)
H12	0.4697	0.6970	0.7730	0.043*
C13	0.7936 (4)	0.7445 (4)	0.8021 (2)	0.0434 (10)
H13	0.8888	0.7079	0.8058	0.052*
C14	0.6960 (4)	0.6839 (4)	0.8622 (2)	0.0462 (10)
H14A	0.6416	0.6152	0.8407	0.055*
H14B	0.7523	0.6508	0.9030	0.055*
C15	0.5975 (4)	0.7878 (4)	0.88991 (19)	0.0381 (9)
H15	0.5191	0.7523	0.9190	0.046*
C16	0.6861 (4)	0.8796 (4)	0.9376 (2)	0.0437 (10)
H16	0.6328	0.9586	0.9424	0.052*
C17	0.8239 (4)	0.9083 (4)	0.8940 (2)	0.0467 (10)
H17	0.8968	0.8497	0.9117	0.056*
C18	0.8788 (5)	1.0421 (5)	0.9065 (3)	0.0663 (14)
H18A	0.9646	1.0542	0.8787	0.100*
H18B	0.8975	1.0545	0.9587	0.100*
H18C	0.8089	1.1019	0.8902	0.100*
C19	0.7203 (5)	0.8328 (5)	1.0151 (2)	0.0565 (12)
H19A	0.7684	0.7520	1.0121	0.068*
H19B	0.7828	0.8921	1.0399	0.068*
C20	0.2370 (4)	0.8146 (4)	0.7544 (2)	0.0436 (10)
C21	0.1183 (4)	0.8719 (5)	0.7135 (2)	0.0533 (11)
H21A	0.1543	0.9200	0.6722	0.080*
H21B	0.0663	0.9266	0.7463	0.080*
H21C	0.0568	0.8067	0.6953	0.080*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.057 (2)	0.155 (4)	0.0534 (18)	−0.013 (3)	−0.0072 (16)	0.036 (2)
O2	0.0300 (13)	0.0513 (17)	0.0407 (13)	0.0002 (13)	0.0000 (11)	0.0085 (13)
O3	0.053 (2)	0.103 (3)	0.0559 (18)	0.001 (2)	0.0102 (16)	0.0321 (19)
N1	0.046 (2)	0.047 (2)	0.055 (2)	0.0073 (19)	0.0066 (17)	−0.0042 (17)
N2	0.0343 (17)	0.0384 (19)	0.0484 (18)	−0.0041 (16)	0.0000 (14)	−0.0012 (15)
C1	0.047 (2)	0.045 (2)	0.0381 (19)	−0.003 (2)	0.0084 (17)	0.0039 (18)
C2	0.056 (3)	0.054 (3)	0.044 (2)	−0.007 (2)	0.000 (2)	0.0044 (19)
C3	0.071 (3)	0.061 (3)	0.041 (2)	−0.010 (3)	−0.001 (2)	0.003 (2)
C4	0.086 (4)	0.059 (3)	0.046 (2)	−0.007 (3)	0.017 (3)	−0.009 (2)
C5	0.068 (3)	0.055 (3)	0.054 (3)	−0.002 (3)	0.016 (2)	−0.009 (2)
C6	0.050 (2)	0.041 (2)	0.047 (2)	−0.003 (2)	0.0136 (19)	0.000 (2)
C7	0.036 (2)	0.035 (2)	0.049 (2)	0.0027 (18)	0.0064 (18)	0.0001 (17)
C8	0.038 (2)	0.038 (2)	0.0389 (19)	−0.0002 (19)	0.0020 (17)	0.0041 (17)
C9	0.041 (2)	0.037 (2)	0.047 (2)	0.0024 (19)	0.0058 (18)	0.0039 (18)
C10	0.038 (2)	0.036 (2)	0.049 (2)	0.0001 (19)	0.0009 (18)	0.0024 (18)
C11	0.033 (2)	0.043 (2)	0.0401 (19)	0.0021 (19)	0.0043 (17)	0.0015 (18)
C12	0.0337 (19)	0.036 (2)	0.0374 (19)	0.0053 (19)	−0.0009 (16)	0.0054 (16)
C13	0.040 (2)	0.043 (2)	0.047 (2)	0.009 (2)	0.0018 (18)	0.0001 (19)
C14	0.045 (2)	0.039 (2)	0.055 (2)	0.003 (2)	−0.004 (2)	0.0075 (19)
C15	0.032 (2)	0.044 (2)	0.0377 (19)	−0.0013 (19)	0.0016 (17)	0.0059 (17)
C16	0.034 (2)	0.050 (2)	0.047 (2)	0.004 (2)	−0.0006 (18)	0.0032 (19)
C17	0.037 (2)	0.053 (3)	0.050 (2)	0.001 (2)	0.0000 (19)	−0.001 (2)
C18	0.064 (3)	0.066 (3)	0.069 (3)	−0.025 (3)	0.000 (3)	−0.011 (3)
C19	0.046 (3)	0.076 (3)	0.048 (2)	0.000 (3)	−0.006 (2)	0.006 (2)
C20	0.037 (2)	0.057 (3)	0.036 (2)	−0.003 (2)	0.0076 (17)	−0.001 (2)
C21	0.036 (2)	0.075 (3)	0.049 (2)	0.000 (2)	0.000 (2)	0.000 (2)

Geometric parameters (Å, º)

O1—C19	1.405 (5)	C10—C11	1.556 (5)
O1—H1	0.8200	C10—H10	0.9800
O2—C20	1.346 (4)	C11—C12	1.533 (5)
O2—C12	1.454 (4)	C11—C15	1.547 (5)
O3—C20	1.207 (5)	C11—H11	0.9800
N1—C7	1.282 (4)	C12—H12	0.9800
N1—C6	1.430 (5)	C13—C14	1.556 (5)
N2—C10	1.469 (5)	C13—H13	0.9800
N2—C13	1.491 (5)	C14—C15	1.524 (5)
N2—C17	1.492 (5)	C14—H14A	0.9700
C1—C2	1.371 (5)	C14—H14B	0.9700
C1—C6	1.406 (6)	C15—C16	1.541 (5)
C1—C8	1.492 (5)	C15—H15	0.9800
C2—C3	1.391 (6)	C16—C19	1.511 (5)
C2—H2	0.9300	C16—C17	1.547 (6)
C3—C4	1.383 (6)	C16—H16	0.9800
C3—H3	0.9300	C17—C18	1.525 (6)
C4—C5	1.380 (7)	C17—H17	0.9800
C4—H4	0.9300	C18—H18A	0.9600
C5—C6	1.380 (5)	C18—H18B	0.9600
C5—H5	0.9300	C18—H18C	0.9600
C7—C13	1.493 (5)	C19—H19A	0.9700
C7—C8	1.512 (5)	C19—H19B	0.9700
C8—C12	1.527 (5)	C20—C21	1.469 (6)
C8—C9	1.549 (5)	C21—H21A	0.9600
C9—C10	1.517 (5)	C21—H21B	0.9600
C9—H9A	0.9700	C21—H21C	0.9600
C9—H9B	0.9700
C19—O1—H1	109.5	O2—C12—H12	111.2
C20—O2—C12	117.1 (3)	C8—C12—H12	111.2
C7—N1—C6	106.2 (3)	C11—C12—H12	111.2
C10—N2—C13	108.7 (3)	N2—C13—C7	109.0 (3)
C10—N2—C17	108.8 (3)	N2—C13—C14	110.6 (3)
C13—N2—C17	107.7 (3)	C7—C13—C14	109.1 (3)
C2—C1—C6	119.7 (4)	N2—C13—H13	109.4
C2—C1—C8	134.3 (4)	C7—C13—H13	109.4
C6—C1—C8	106.0 (3)	C14—C13—H13	109.4
C1—C2—C3	119.5 (4)	C15—C14—C13	106.8 (3)
C1—C2—H2	120.2	C15—C14—H14A	110.4
C3—C2—H2	120.2	C13—C14—H14A	110.4
C4—C3—C2	120.0 (4)	C15—C14—H14B	110.4
C4—C3—H3	120.0	C13—C14—H14B	110.4
C2—C3—H3	120.0	H14A—C14—H14B	108.6
C5—C4—C3	121.5 (4)	C14—C15—C16	107.8 (3)
C5—C4—H4	119.3	C14—C15—C11	109.6 (3)
C3—C4—H4	119.3	C16—C15—C11	106.7 (3)
C4—C5—C6	118.1 (4)	C14—C15—H15	110.9
C4—C5—H5	120.9	C16—C15—H15	110.9
C6—C5—H5	120.9	C11—C15—H15	110.9
C5—C6—C1	121.1 (4)	C19—C16—C15	114.8 (4)
C5—C6—N1	126.8 (4)	C19—C16—C17	110.5 (3)
C1—C6—N1	112.0 (3)	C15—C16—C17	107.4 (3)
N1—C7—C13	125.4 (4)	C19—C16—H16	108.0
N1—C7—C8	114.8 (3)	C15—C16—H16	108.0
C13—C7—C8	119.8 (3)	C17—C16—H16	108.0
C1—C8—C7	100.9 (3)	N2—C17—C18	110.6 (3)
C1—C8—C12	120.1 (3)	N2—C17—C16	110.2 (3)
C7—C8—C12	110.0 (3)	C18—C17—C16	113.2 (3)
C1—C8—C9	119.8 (3)	N2—C17—H17	107.6
C7—C8—C9	104.5 (3)	C18—C17—H17	107.6
C12—C8—C9	100.6 (3)	C16—C17—H17	107.6
C10—C9—C8	99.8 (3)	C17—C18—H18A	109.5
C10—C9—H9A	111.8	C17—C18—H18B	109.5
C8—C9—H9A	111.8	H18A—C18—H18B	109.5
C10—C9—H9B	111.8	C17—C18—H18C	109.5
C8—C9—H9B	111.8	H18A—C18—H18C	109.5
H9A—C9—H9B	109.5	H18B—C18—H18C	109.5
N2—C10—C9	110.2 (3)	O1—C19—C16	109.7 (3)
N2—C10—C11	110.1 (3)	O1—C19—H19A	109.7
C9—C10—C11	105.0 (3)	C16—C19—H19A	109.7
N2—C10—H10	110.5	O1—C19—H19B	109.7
C9—C10—H10	110.5	C16—C19—H19B	109.7
C11—C10—H10	110.5	H19A—C19—H19B	108.2
C12—C11—C15	114.6 (3)	O3—C20—O2	120.9 (4)
C12—C11—C10	104.3 (3)	O3—C20—C21	126.6 (4)
C15—C11—C10	107.8 (3)	O2—C20—C21	112.5 (3)
C12—C11—H11	110.0	C20—C21—H21A	109.5
C15—C11—H11	110.0	C20—C21—H21B	109.5
C10—C11—H11	110.0	H21A—C21—H21B	109.5
O2—C12—C8	106.4 (3)	C20—C21—H21C	109.5
O2—C12—C11	111.7 (3)	H21A—C21—H21C	109.5
C8—C12—C11	105.0 (3)	H21B—C21—H21C	109.5
N2—C10—C11—C15	20.2 (4)	C20—O2—C12—C8	162.4 (3)
N2—C13—C14—C15	23.0 (4)	C20—O2—C12—C11	−83.5 (4)
N2—C17—C16—C15	22.5 (4)	C1—C8—C12—O2	−55.5 (4)
C6—C1—C2—C3	0.1 (6)	C7—C8—C12—O2	−171.8 (3)
C8—C1—C2—C3	−179.7 (4)	C9—C8—C12—O2	78.3 (3)
C1—C2—C3—C4	1.5 (7)	C1—C8—C12—C11	−174.0 (3)
C2—C3—C4—C5	−2.3 (7)	C7—C8—C12—C11	69.6 (4)
C3—C4—C5—C6	1.4 (7)	C9—C8—C12—C11	−40.2 (3)
C4—C5—C6—C1	0.2 (6)	C15—C11—C12—O2	142.4 (3)
C4—C5—C6—N1	179.5 (4)	C10—C11—C12—O2	−100.0 (3)
C2—C1—C6—C5	−0.9 (6)	C15—C11—C12—C8	−102.7 (3)
C8—C1—C6—C5	179.0 (4)	C10—C11—C12—C8	14.9 (4)
C2—C1—C6—N1	179.7 (4)	C10—N2—C13—C7	47.1 (4)
C8—C1—C6—N1	−0.4 (4)	C17—N2—C13—C7	164.9 (3)
C7—N1—C6—C5	−178.7 (4)	C10—N2—C13—C14	−72.8 (4)
C7—N1—C6—C1	0.7 (4)	C17—N2—C13—C14	45.0 (4)
C6—N1—C7—C13	179.3 (4)	N1—C7—C13—N2	134.9 (4)
C6—N1—C7—C8	−0.7 (4)	C8—C7—C13—N2	−45.2 (5)
C2—C1—C8—C7	179.9 (5)	N1—C7—C13—C14	−104.2 (4)
C6—C1—C8—C7	0.1 (4)	C8—C7—C13—C14	75.7 (4)
C2—C1—C8—C12	58.9 (6)	C7—C13—C14—C15	−96.9 (4)
C6—C1—C8—C12	−120.9 (4)	C13—C14—C15—C16	−71.7 (4)
C2—C1—C8—C9	−66.3 (6)	C13—C14—C15—C11	44.0 (4)
C6—C1—C8—C9	113.9 (4)	C12—C11—C15—C14	46.5 (4)
N1—C7—C8—C1	0.4 (4)	C10—C11—C15—C14	−69.1 (4)
C13—C7—C8—C1	−179.5 (3)	C12—C11—C15—C16	162.9 (3)
N1—C7—C8—C12	128.3 (4)	C10—C11—C15—C16	47.3 (4)
C13—C7—C8—C12	−51.7 (5)	C14—C15—C16—C19	−77.0 (4)
N1—C7—C8—C9	−124.5 (4)	C11—C15—C16—C19	165.4 (3)
C13—C7—C8—C9	55.6 (4)	C14—C15—C16—C17	46.4 (4)
C1—C8—C9—C10	−176.2 (4)	C11—C15—C16—C17	−71.2 (4)
C7—C8—C9—C10	−64.3 (3)	C10—N2—C17—C18	−79.8 (4)
C12—C8—C9—C10	49.8 (3)	C13—N2—C17—C18	162.5 (3)
C13—N2—C10—C9	−69.3 (4)	C10—N2—C17—C16	46.1 (4)
C17—N2—C10—C9	173.6 (3)	C13—N2—C17—C16	−71.7 (4)
C13—N2—C10—C11	46.1 (4)	C19—C16—C17—N2	148.4 (3)
C17—N2—C10—C11	−71.0 (4)	C19—C16—C17—C18	−87.3 (5)
C8—C9—C10—N2	77.5 (4)	C15—C16—C17—C18	146.8 (4)
C8—C9—C10—C11	−41.1 (4)	C15—C16—C19—O1	−64.3 (5)
N2—C10—C11—C12	−102.0 (3)	C17—C16—C19—O1	174.0 (4)
C9—C10—C11—C12	16.7 (4)	C12—O2—C20—O3	1.5 (6)
C9—C10—C11—C15	138.9 (3)	C12—O2—C20—C21	−178.3 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O3^i	0.82	2.03	2.810 (4)	160

Symmetry code: (i) x+1/2, −y+3/2, −z+2.