organic compounds
2,2-Bis(1H-indol-3-yl)indolin-3-one
aGraduate School, The Chinese Academy of Sciences, Beijing 100039, People's Republic of China, and bThe State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
*Correspondence e-mail: xujing@fjirsm.ac.cn
In the title molecule, C24H17N3O, the mean plane of the indolone ring forms dihedral angles of 112.0 (1) and 103.1 (1)° with the planes of the two indole rings. The dihedral angle between the mean planes of the two indole rings is 63.5 (1)°. In the molecules are linked via intermolecular N—H⋯O hydrogen bonds, forming a two-dimensional network parallel to the ab plane.
Related literature
For the applications of indole derivatives, see: Ramesh et al. (2009). For the isolation of the title compound as a natural product, see: Ganachaud et al. (2008); Stull et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku/MSC, 2005); cell CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536809017553/lh2811sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809017553/lh2811Isup2.hkl
The title compound was obtained from a mixture of 1H-indole (78 mg) with tBuCOOH (0.18 ml) and H3PMo12O14 (9 mg) in toluene (1 ml) and CH3COOH (1 ml) under a nitrogen atmosphere at room temperature for 24 h. The crude product was isolated and purified by silica gel columnchromatography. Yellow prism-shaped crystals of (I) suitable for X-ray diffraction were grown by slow evaporation of a dichloromethane solution at room temperature.
H atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H = 0.93 Å; N—H = 0.86 Å and Uiso(H) = 1.2Ueq(C,N).
Data collection: CrystalClear (Rigaku/MSC, 2005); cell
CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C24H17N3O | F(000) = 760 |
Mr = 363.41 | Dx = 1.300 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 4234 reflections |
a = 10.559 (4) Å | θ = 3.0–27.5° |
b = 8.931 (3) Å | µ = 0.08 mm−1 |
c = 19.899 (7) Å | T = 293 K |
β = 98.480 (6)° | Prism, yellow |
V = 1856.1 (11) Å3 | 0.40 × 0.35 × 0.15 mm |
Z = 4 |
Rigaku Mercury CCD diffractometer | 4245 independent reflections |
Radiation source: fine-focus sealed tube | 3606 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
Detector resolution: 14.6306 pixels mm-1 | θmax = 27.5°, θmin = 2.1° |
CCD_Profile_fitting scans | h = −11→13 |
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005) | k = −11→11 |
Tmin = 0.968, Tmax = 0.988 | l = −22→25 |
14004 measured reflections |
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)] = 0.048 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.118 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0513P)2 + 0.4603P] where P = (Fo2 + 2Fc2)/3 |
4245 reflections | (Δ/σ)max < 0.001 |
253 parameters | Δρmax = 0.21 e Å−3 |
0 restraints | Δρmin = −0.19 e Å−3 |
C24H17N3O | V = 1856.1 (11) Å3 |
Mr = 363.41 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 10.559 (4) Å | µ = 0.08 mm−1 |
b = 8.931 (3) Å | T = 293 K |
c = 19.899 (7) Å | 0.40 × 0.35 × 0.15 mm |
β = 98.480 (6)° |
Rigaku Mercury CCD diffractometer | 4245 independent reflections |
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005) | 3606 reflections with I > 2σ(I) |
Tmin = 0.968, Tmax = 0.988 | Rint = 0.024 |
14004 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.118 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.21 e Å−3 |
4245 reflections | Δρmin = −0.19 e Å−3 |
253 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.96565 (9) | 0.43252 (10) | 0.15911 (5) | 0.0369 (2) | |
N1 | 0.95403 (12) | 0.04726 (13) | 0.11858 (6) | 0.0406 (3) | |
H1A | 0.9668 | −0.0474 | 0.1239 | 0.049* | |
N2 | 0.75509 (12) | 0.05077 (15) | 0.28328 (7) | 0.0490 (3) | |
H2B | 0.6914 | −0.0017 | 0.2923 | 0.059* | |
N3 | 1.31856 (12) | 0.10180 (15) | 0.26178 (6) | 0.0471 (3) | |
H3B | 1.3724 | 0.0659 | 0.2945 | 0.056* | |
C1 | 0.89773 (13) | 0.11138 (16) | 0.05986 (7) | 0.0374 (3) | |
C2 | 0.85094 (14) | 0.0420 (2) | −0.00189 (8) | 0.0483 (4) | |
H2A | 0.8532 | −0.0615 | −0.0065 | 0.058* | |
C3 | 0.80181 (17) | 0.1314 (2) | −0.05518 (8) | 0.0635 (5) | |
H3A | 0.7706 | 0.0868 | −0.0966 | 0.076* | |
C4 | 0.7967 (2) | 0.2867 (3) | −0.04991 (9) | 0.0746 (6) | |
H4A | 0.7630 | 0.3437 | −0.0874 | 0.090* | |
C5 | 0.84151 (19) | 0.3558 (2) | 0.01064 (8) | 0.0604 (5) | |
H5A | 0.8383 | 0.4595 | 0.0147 | 0.072* | |
C6 | 0.89185 (13) | 0.26719 (17) | 0.06585 (7) | 0.0392 (3) | |
C7 | 0.94976 (12) | 0.30732 (14) | 0.13383 (6) | 0.0315 (3) | |
C8 | 0.99057 (13) | 0.15946 (14) | 0.17220 (6) | 0.0321 (3) | |
C9 | 0.81798 (14) | 0.15783 (17) | 0.32497 (7) | 0.0417 (3) | |
C10 | 0.79721 (18) | 0.2065 (2) | 0.38885 (8) | 0.0557 (4) | |
H10A | 0.7324 | 0.1655 | 0.4100 | 0.067* | |
C11 | 0.8753 (2) | 0.3166 (2) | 0.41938 (8) | 0.0616 (5) | |
H11A | 0.8635 | 0.3509 | 0.4621 | 0.074* | |
C12 | 0.97253 (17) | 0.3786 (2) | 0.38756 (8) | 0.0550 (4) | |
H12A | 1.0236 | 0.4541 | 0.4093 | 0.066* | |
C13 | 0.99417 (15) | 0.32982 (17) | 0.32449 (7) | 0.0424 (3) | |
H13A | 1.0597 | 0.3712 | 0.3040 | 0.051* | |
C14 | 0.91605 (13) | 0.21709 (15) | 0.29179 (7) | 0.0351 (3) | |
C15 | 0.90865 (13) | 0.13904 (15) | 0.22798 (7) | 0.0342 (3) | |
C16 | 0.80919 (14) | 0.04053 (17) | 0.22537 (8) | 0.0432 (3) | |
H16A | 0.7823 | −0.0240 | 0.1894 | 0.052* | |
C17 | 1.34968 (13) | 0.18478 (15) | 0.20847 (7) | 0.0380 (3) | |
C18 | 1.46884 (15) | 0.23042 (18) | 0.19416 (9) | 0.0491 (4) | |
H18A | 1.5436 | 0.2065 | 0.2230 | 0.059* | |
C19 | 1.47219 (15) | 0.31203 (18) | 0.13592 (9) | 0.0511 (4) | |
H19A | 1.5507 | 0.3436 | 0.1251 | 0.061* | |
C20 | 1.36003 (15) | 0.34840 (18) | 0.09265 (8) | 0.0461 (4) | |
H20A | 1.3651 | 0.4030 | 0.0533 | 0.055* | |
C21 | 1.24194 (14) | 0.30469 (15) | 0.10722 (7) | 0.0380 (3) | |
H21A | 1.1679 | 0.3304 | 0.0782 | 0.046* | |
C22 | 1.23417 (12) | 0.22113 (14) | 0.16619 (6) | 0.0322 (3) | |
C23 | 1.13200 (12) | 0.15690 (14) | 0.19763 (6) | 0.0326 (3) | |
C24 | 1.18882 (14) | 0.08515 (16) | 0.25473 (7) | 0.0412 (3) | |
H24A | 1.1454 | 0.0325 | 0.2846 | 0.049* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0351 (5) | 0.0344 (5) | 0.0407 (5) | 0.0007 (4) | 0.0040 (4) | −0.0052 (4) |
N1 | 0.0497 (7) | 0.0320 (6) | 0.0391 (6) | −0.0014 (5) | 0.0029 (5) | −0.0058 (5) |
N2 | 0.0361 (7) | 0.0527 (8) | 0.0603 (8) | −0.0086 (6) | 0.0138 (6) | 0.0105 (6) |
N3 | 0.0361 (7) | 0.0560 (8) | 0.0472 (7) | 0.0108 (6) | −0.0002 (5) | 0.0156 (6) |
C1 | 0.0288 (7) | 0.0464 (8) | 0.0367 (7) | −0.0010 (6) | 0.0041 (5) | −0.0075 (6) |
C2 | 0.0377 (8) | 0.0583 (9) | 0.0474 (8) | −0.0003 (7) | 0.0016 (6) | −0.0203 (7) |
C3 | 0.0549 (11) | 0.0890 (14) | 0.0415 (9) | 0.0140 (10) | −0.0100 (8) | −0.0235 (9) |
C4 | 0.0916 (16) | 0.0844 (14) | 0.0395 (9) | 0.0287 (12) | −0.0181 (9) | −0.0053 (9) |
C5 | 0.0750 (12) | 0.0580 (10) | 0.0423 (8) | 0.0195 (9) | −0.0110 (8) | −0.0010 (7) |
C6 | 0.0353 (7) | 0.0455 (8) | 0.0347 (7) | 0.0055 (6) | −0.0015 (6) | −0.0053 (6) |
C7 | 0.0252 (6) | 0.0364 (7) | 0.0330 (6) | 0.0018 (5) | 0.0048 (5) | −0.0025 (5) |
C8 | 0.0327 (7) | 0.0322 (6) | 0.0311 (6) | −0.0015 (5) | 0.0034 (5) | −0.0032 (5) |
C9 | 0.0367 (8) | 0.0463 (8) | 0.0437 (8) | 0.0066 (6) | 0.0114 (6) | 0.0125 (6) |
C10 | 0.0577 (10) | 0.0660 (11) | 0.0486 (9) | 0.0120 (9) | 0.0249 (8) | 0.0170 (8) |
C11 | 0.0735 (13) | 0.0775 (13) | 0.0365 (8) | 0.0178 (10) | 0.0174 (8) | 0.0021 (8) |
C12 | 0.0601 (11) | 0.0623 (10) | 0.0419 (8) | 0.0047 (8) | 0.0051 (7) | −0.0090 (7) |
C13 | 0.0425 (8) | 0.0485 (8) | 0.0366 (7) | −0.0009 (6) | 0.0067 (6) | −0.0014 (6) |
C14 | 0.0327 (7) | 0.0391 (7) | 0.0338 (6) | 0.0038 (5) | 0.0058 (5) | 0.0054 (5) |
C15 | 0.0309 (7) | 0.0353 (7) | 0.0359 (7) | −0.0004 (5) | 0.0039 (5) | 0.0026 (5) |
C16 | 0.0367 (8) | 0.0436 (8) | 0.0486 (8) | −0.0051 (6) | 0.0044 (6) | 0.0023 (6) |
C17 | 0.0338 (7) | 0.0366 (7) | 0.0430 (7) | 0.0063 (5) | 0.0037 (6) | 0.0013 (6) |
C18 | 0.0297 (7) | 0.0524 (9) | 0.0640 (10) | 0.0058 (6) | 0.0030 (7) | 0.0001 (8) |
C19 | 0.0359 (8) | 0.0515 (9) | 0.0686 (11) | −0.0027 (7) | 0.0172 (7) | −0.0014 (8) |
C20 | 0.0472 (9) | 0.0473 (8) | 0.0463 (8) | −0.0034 (7) | 0.0154 (7) | 0.0031 (7) |
C21 | 0.0371 (7) | 0.0407 (7) | 0.0359 (7) | 0.0006 (6) | 0.0049 (6) | 0.0006 (6) |
C22 | 0.0313 (7) | 0.0308 (6) | 0.0346 (6) | 0.0036 (5) | 0.0051 (5) | −0.0022 (5) |
C23 | 0.0319 (7) | 0.0327 (6) | 0.0334 (6) | 0.0029 (5) | 0.0056 (5) | 0.0001 (5) |
C24 | 0.0376 (8) | 0.0436 (8) | 0.0428 (8) | 0.0054 (6) | 0.0070 (6) | 0.0096 (6) |
O1—C7 | 1.2274 (16) | C9—C14 | 1.411 (2) |
N1—C1 | 1.3571 (18) | C10—C11 | 1.367 (3) |
N1—C8 | 1.4731 (16) | C10—H10A | 0.9300 |
N1—H1A | 0.8600 | C11—C12 | 1.398 (3) |
N2—C16 | 1.363 (2) | C11—H11A | 0.9300 |
N2—C9 | 1.371 (2) | C12—C13 | 1.379 (2) |
N2—H2B | 0.8600 | C12—H12A | 0.9300 |
N3—C24 | 1.3645 (19) | C13—C14 | 1.400 (2) |
N3—C17 | 1.3731 (19) | C13—H13A | 0.9300 |
N3—H3B | 0.8600 | C14—C15 | 1.4405 (19) |
C1—C6 | 1.399 (2) | C15—C16 | 1.3652 (19) |
C1—C2 | 1.3997 (19) | C16—H16A | 0.9300 |
C2—C3 | 1.367 (3) | C17—C18 | 1.391 (2) |
C2—H2A | 0.9300 | C17—C22 | 1.4136 (19) |
C3—C4 | 1.392 (3) | C18—C19 | 1.374 (2) |
C3—H3A | 0.9300 | C18—H18A | 0.9300 |
C4—C5 | 1.374 (2) | C19—C20 | 1.396 (2) |
C4—H4A | 0.9300 | C19—H19A | 0.9300 |
C5—C6 | 1.394 (2) | C20—C21 | 1.378 (2) |
C5—H5A | 0.9300 | C20—H20A | 0.9300 |
C6—C7 | 1.4451 (18) | C21—C22 | 1.4031 (19) |
C7—C8 | 1.5542 (18) | C21—H21A | 0.9300 |
C8—C23 | 1.5046 (19) | C22—C23 | 1.4434 (18) |
C8—C15 | 1.5155 (19) | C23—C24 | 1.3640 (19) |
C9—C10 | 1.391 (2) | C24—H24A | 0.9300 |
C1—N1—C8 | 111.79 (11) | C10—C11—C12 | 121.26 (16) |
C1—N1—H1A | 124.1 | C10—C11—H11A | 119.4 |
C8—N1—H1A | 124.1 | C12—C11—H11A | 119.4 |
C16—N2—C9 | 109.42 (12) | C13—C12—C11 | 121.24 (17) |
C16—N2—H2B | 125.3 | C13—C12—H12A | 119.4 |
C9—N2—H2B | 125.3 | C11—C12—H12A | 119.4 |
C24—N3—C17 | 109.29 (12) | C12—C13—C14 | 119.00 (15) |
C24—N3—H3B | 125.4 | C12—C13—H13A | 120.5 |
C17—N3—H3B | 125.4 | C14—C13—H13A | 120.5 |
N1—C1—C6 | 111.45 (12) | C13—C14—C9 | 118.37 (13) |
N1—C1—C2 | 128.48 (14) | C13—C14—C15 | 135.19 (13) |
C6—C1—C2 | 120.06 (14) | C9—C14—C15 | 106.43 (13) |
C3—C2—C1 | 117.83 (16) | C16—C15—C14 | 106.67 (12) |
C3—C2—H2A | 121.1 | C16—C15—C8 | 124.66 (13) |
C1—C2—H2A | 121.1 | C14—C15—C8 | 128.66 (12) |
C2—C3—C4 | 122.53 (15) | N2—C16—C15 | 109.91 (14) |
C2—C3—H3A | 118.7 | N2—C16—H16A | 125.0 |
C4—C3—H3A | 118.7 | C15—C16—H16A | 125.0 |
C5—C4—C3 | 120.11 (17) | N3—C17—C18 | 130.01 (13) |
C5—C4—H4A | 119.9 | N3—C17—C22 | 107.46 (12) |
C3—C4—H4A | 119.9 | C18—C17—C22 | 122.53 (14) |
C4—C5—C6 | 118.52 (17) | C19—C18—C17 | 117.69 (14) |
C4—C5—H5A | 120.7 | C19—C18—H18A | 121.2 |
C6—C5—H5A | 120.7 | C17—C18—H18A | 121.2 |
C5—C6—C1 | 120.95 (14) | C18—C19—C20 | 121.24 (14) |
C5—C6—C7 | 131.01 (14) | C18—C19—H19A | 119.4 |
C1—C6—C7 | 107.97 (12) | C20—C19—H19A | 119.4 |
O1—C7—C6 | 128.53 (13) | C21—C20—C19 | 121.07 (14) |
O1—C7—C8 | 124.16 (12) | C21—C20—H20A | 119.5 |
C6—C7—C8 | 107.31 (11) | C19—C20—H20A | 119.5 |
N1—C8—C23 | 111.98 (11) | C20—C21—C22 | 119.54 (13) |
N1—C8—C15 | 109.37 (11) | C20—C21—H21A | 120.2 |
C23—C8—C15 | 113.41 (11) | C22—C21—H21A | 120.2 |
N1—C8—C7 | 101.43 (10) | C21—C22—C17 | 117.92 (12) |
C23—C8—C7 | 111.57 (10) | C21—C22—C23 | 135.52 (12) |
C15—C8—C7 | 108.37 (11) | C17—C22—C23 | 106.56 (12) |
N2—C9—C10 | 130.02 (15) | C24—C23—C22 | 106.43 (12) |
N2—C9—C14 | 107.57 (13) | C24—C23—C8 | 125.45 (12) |
C10—C9—C14 | 122.41 (15) | C22—C23—C8 | 128.05 (11) |
C11—C10—C9 | 117.71 (15) | C23—C24—N3 | 110.25 (13) |
C11—C10—H10A | 121.1 | C23—C24—H24A | 124.9 |
C9—C10—H10A | 121.1 | N3—C24—H24A | 124.9 |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2B···O1i | 0.86 | 2.12 | 2.9412 (17) | 159 |
N3—H3B···O1ii | 0.86 | 2.18 | 2.9830 (16) | 156 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+5/2, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C24H17N3O |
Mr | 363.41 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 10.559 (4), 8.931 (3), 19.899 (7) |
β (°) | 98.480 (6) |
V (Å3) | 1856.1 (11) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.40 × 0.35 × 0.15 |
Data collection | |
Diffractometer | Rigaku Mercury CCD diffractometer |
Absorption correction | Multi-scan (CrystalClear; Rigaku/MSC, 2005) |
Tmin, Tmax | 0.968, 0.988 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14004, 4245, 3606 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.118, 1.06 |
No. of reflections | 4245 |
No. of parameters | 253 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.21, −0.19 |
Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2B···O1i | 0.86 | 2.12 | 2.9412 (17) | 159.0 |
N3—H3B···O1ii | 0.86 | 2.18 | 2.9830 (16) | 156.3 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+5/2, y−1/2, −z+1/2. |
Acknowledgements
This work was supported by the Natural Science Foundation of Fujian province (grant No. 2006 J0273) and the `One Hundred Talent' Projects from the Chinese Academy of Sciences.
References
Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
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Indole derivatives are used as bioactive drugs and they exibit anti-allergic, central nervous system depressant and muscle relaxant properties (Ramesh et al., 2009). The title compound is a natural product that has been isolated from bacterial sources (Stull et al.., 1995; Ganachaud et al.., 2008). Recently, we found different indole derivatives could be formed by oxidation solely on the basis of the reaction solvent and temperature. As part of our studies, we report herein the synthesis and crystal structure of the title compound (I) (Fig. 1).
The title compound is a trimeric condensation product of indole through the formation of a quaternary carbon (C8) centre. The indolone ring forms dihedral angle of 112.0 (1)° and 103.1 (1)°, respectively, with the two indole rings (C9/C10/C11/C12/C13/C14/C15/C16/N2) and (C17/C18/C19/C20/C21/C22/C23/C24/N3). The mean planes of the two indole form a dihedral angle of 63.5 (1)°. In the crystal structure, the carbonyl atom O1 acts as a bifurcated acceptor for the N-H groups of atoms N2 and N3 to form a two-dimensional network parallel to the ab plane (Table 1, Fig. 2).