5-Meth-oxy-1-[(5-meth-oxy-1H-indol-2-yl)meth-yl]-1H-indole.

In the title compound, C(19)H(18)N(2)O(2), the two indole ring systems are essentially planar [maximum deviation = 0.015 (2) Å in both indole ring systems] and make a dihedral angle of 72.17 (7)° with each other. In the crystal, the mol-ecules are linked into a zigzag chain along the a axis via N-H⋯O hydrogen bonds.

Related literature

For the biological activity of melatonin (MLT), see: Csernus & Mess (2003 ▶); Nosjean et al. (2000 ▶); Blask et al. (2002 ▶); Genovese et al. (2005 ▶); Mills et al. (2005 ▶); Peres (2005 ▶); Sofic et al. (2005 ▶); Witt-Enderby et al. (2006 ▶). For related structures, see: Narayanan et al. (2011 ▶); Deng et al. (2011 ▶). For the synthesis, see: Attia et al. (2008 ▶).

Experimental

Crystal data

C19H18N2O2

M = 306.35

Monoclinic,

a = 9.4446 (5) Å

b = 19.5625 (8) Å

c = 8.6657 (5) Å

β = 98.903 (4)°

V = 1581.78 (14) Å3

Z = 4

Cu Kα radiation

μ = 0.68 mm−1

T = 296 K

0.92 × 0.20 × 0.06 mm

Data collection

Bruker APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.575, T max = 0.961

9421 measured reflections

2584 independent reflections

2087 reflections with I > 2σ(I)

R int = 0.041

Refinement

R[F 2 > 2σ(F 2)] = 0.046

wR(F 2) = 0.133

S = 1.06

2584 reflections

215 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.15 e Å−3

Δρmin = −0.14 e Å−3

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; 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 and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812009257/is5084sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812009257/is5084Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812009257/is5084Isup3.cml

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

C19H18N2O2	F(000) = 648
Mr = 306.35	Dx = 1.286 Mg m−3
Monoclinic, P21/c	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybc	Cell parameters from 919 reflections
a = 9.4446 (5) Å	θ = 4.5–60.8°
b = 19.5625 (8) Å	µ = 0.68 mm−1
c = 8.6657 (5) Å	T = 296 K
β = 98.903 (4)°	Plate, pink
V = 1581.78 (14) Å3	0.92 × 0.20 × 0.06 mm
Z = 4

Bruker APEXII CCD diffractometer	2584 independent reflections
Radiation source: fine-focus sealed tube	2087 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.041
φ and ω scans	θmax = 65.0°, θmin = 4.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −11→11
Tmin = 0.575, Tmax = 0.961	k = −22→22
9421 measured reflections	l = −8→9

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.046	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.133	w = 1/[σ2(Fo2) + (0.0478P)2 + 0.3465P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max < 0.001
2584 reflections	Δρmax = 0.15 e Å−3
215 parameters	Δρmin = −0.14 e Å−3
0 restraints	Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0029 (5)

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
N1	0.57956 (17)	0.66569 (8)	0.6878 (2)	0.0604 (4)
N2	0.32036 (18)	0.76234 (9)	0.5805 (2)	0.0588 (4)
O1	1.08253 (15)	0.66541 (8)	0.44352 (19)	0.0727 (5)
O2	0.1802 (2)	1.02435 (9)	0.3902 (2)	0.0978 (6)
C1	0.4392 (2)	0.77296 (11)	0.6916 (2)	0.0573 (5)
C2	0.4672 (2)	0.84059 (11)	0.7021 (2)	0.0616 (5)
H2A	0.5421	0.8610	0.7683	0.074*
C3	0.36179 (19)	0.87542 (10)	0.5938 (2)	0.0536 (5)
C4	0.3345 (2)	0.94428 (11)	0.5531 (3)	0.0644 (6)
H4A	0.3924	0.9789	0.6018	0.077*
C5	0.2203 (2)	0.95918 (11)	0.4396 (3)	0.0675 (6)
C6	0.1345 (2)	0.90736 (12)	0.3641 (3)	0.0703 (6)
H6A	0.0593	0.9188	0.2859	0.084*
C7	0.1585 (2)	0.84013 (12)	0.4025 (3)	0.0661 (6)
H7A	0.1008	0.8059	0.3519	0.079*
C8	0.27154 (19)	0.82467 (9)	0.5191 (2)	0.0529 (5)
C9	0.5147 (2)	0.71548 (12)	0.7821 (3)	0.0709 (6)
H9A	0.5893	0.7342	0.8602	0.085*
H9B	0.4470	0.6918	0.8368	0.085*
C10	0.5303 (2)	0.60163 (11)	0.6481 (3)	0.0728 (6)
H10A	0.4461	0.5831	0.6732	0.087*
C11	0.6216 (2)	0.56865 (11)	0.5667 (3)	0.0704 (6)
H11A	0.6112	0.5244	0.5271	0.084*
C12	0.73578 (19)	0.61433 (9)	0.5536 (2)	0.0535 (5)
C13	0.86132 (19)	0.60976 (9)	0.4852 (2)	0.0552 (5)
H13A	0.8813	0.5708	0.4311	0.066*
C14	0.95290 (19)	0.66412 (10)	0.5005 (2)	0.0538 (5)
C15	0.9232 (2)	0.72402 (10)	0.5783 (2)	0.0565 (5)
H15A	0.9874	0.7603	0.5852	0.068*
C16	0.8003 (2)	0.72991 (9)	0.6444 (2)	0.0548 (5)
H16A	0.7802	0.7696	0.6961	0.066*
C17	0.70772 (19)	0.67448 (9)	0.6312 (2)	0.0505 (4)
C18	1.1240 (3)	0.60545 (15)	0.3717 (4)	0.0934 (8)
H18A	1.2164	0.6122	0.3411	0.140*
H18B	1.0550	0.5953	0.2811	0.140*
H18C	1.1287	0.5680	0.4440	0.140*
C19	0.2324 (3)	1.07922 (13)	0.4857 (4)	0.1022 (9)
H19A	0.1819	1.1201	0.4492	0.153*
H19C	0.3328	1.0851	0.4823	0.153*
H19D	0.2184	1.0701	0.5911	0.153*
H1N2	0.274 (3)	0.7238 (12)	0.559 (3)	0.072 (7)*

	U11	U22	U33	U12	U13	U23
N1	0.0524 (9)	0.0644 (10)	0.0664 (11)	0.0041 (7)	0.0159 (7)	0.0093 (8)
N2	0.0544 (9)	0.0598 (10)	0.0637 (11)	−0.0052 (8)	0.0135 (7)	0.0005 (8)
O1	0.0617 (8)	0.0756 (10)	0.0863 (11)	−0.0066 (7)	0.0287 (7)	−0.0043 (8)
O2	0.1246 (15)	0.0672 (10)	0.0933 (14)	0.0037 (9)	−0.0091 (11)	0.0129 (9)
C1	0.0501 (10)	0.0742 (13)	0.0501 (12)	0.0041 (9)	0.0153 (8)	−0.0015 (9)
C2	0.0528 (11)	0.0777 (14)	0.0531 (12)	−0.0001 (9)	0.0040 (8)	−0.0115 (9)
C3	0.0514 (10)	0.0635 (11)	0.0475 (11)	−0.0020 (8)	0.0132 (8)	−0.0084 (8)
C4	0.0669 (12)	0.0638 (13)	0.0615 (13)	−0.0084 (10)	0.0073 (10)	−0.0102 (9)
C5	0.0758 (13)	0.0634 (12)	0.0624 (14)	0.0007 (10)	0.0078 (10)	0.0034 (10)
C6	0.0682 (13)	0.0769 (14)	0.0617 (14)	−0.0004 (11)	−0.0031 (10)	0.0038 (10)
C7	0.0601 (12)	0.0718 (14)	0.0634 (13)	−0.0117 (10)	0.0005 (10)	−0.0038 (10)
C8	0.0495 (10)	0.0603 (11)	0.0513 (11)	−0.0038 (8)	0.0147 (8)	−0.0033 (8)
C9	0.0676 (13)	0.0903 (16)	0.0584 (14)	0.0158 (11)	0.0217 (10)	0.0089 (11)
C10	0.0542 (11)	0.0711 (14)	0.0938 (18)	−0.0107 (10)	0.0132 (11)	0.0141 (12)
C11	0.0587 (12)	0.0594 (12)	0.0917 (17)	−0.0093 (10)	0.0079 (11)	−0.0037 (11)
C12	0.0482 (10)	0.0538 (10)	0.0563 (12)	−0.0028 (8)	0.0015 (8)	0.0027 (8)
C13	0.0543 (10)	0.0534 (10)	0.0569 (12)	0.0020 (8)	0.0061 (8)	−0.0050 (8)
C14	0.0486 (10)	0.0600 (11)	0.0534 (11)	−0.0017 (8)	0.0097 (8)	0.0042 (8)
C15	0.0546 (10)	0.0527 (11)	0.0618 (13)	−0.0058 (8)	0.0078 (8)	0.0018 (8)
C16	0.0592 (11)	0.0502 (10)	0.0538 (12)	0.0011 (8)	0.0053 (8)	−0.0016 (8)
C17	0.0479 (9)	0.0530 (10)	0.0502 (10)	0.0031 (8)	0.0064 (7)	0.0072 (8)
C18	0.0780 (16)	0.1011 (19)	0.110 (2)	0.0006 (14)	0.0436 (14)	−0.0225 (15)
C19	0.112 (2)	0.0623 (15)	0.128 (3)	0.0008 (14)	0.0042 (18)	0.0030 (15)

N1—C10	1.362 (3)	C7—H7A	0.9300
N1—C17	1.385 (2)	C9—H9A	0.9700
N1—C9	1.465 (3)	C9—H9B	0.9700
N2—C1	1.377 (3)	C10—C11	1.359 (3)
N2—C8	1.381 (3)	C10—H10A	0.9300
N2—H1N2	0.88 (2)	C11—C12	1.419 (3)
O1—C14	1.390 (2)	C11—H11A	0.9300
O1—C18	1.411 (3)	C12—C17	1.401 (3)
O2—C5	1.379 (3)	C12—C13	1.408 (3)
O2—C19	1.398 (3)	C13—C14	1.364 (3)
C1—C2	1.349 (3)	C13—H13A	0.9300
C1—C9	1.488 (3)	C14—C15	1.402 (3)
C2—C3	1.431 (3)	C15—C16	1.376 (3)
C2—H2A	0.9300	C15—H15A	0.9300
C3—C8	1.400 (3)	C16—C17	1.387 (3)
C3—C4	1.406 (3)	C16—H16A	0.9300
C4—C5	1.374 (3)	C18—H18A	0.9600
C4—H4A	0.9300	C18—H18B	0.9600
C5—C6	1.396 (3)	C18—H18C	0.9600
C6—C7	1.367 (3)	C19—H19A	0.9600
C6—H6A	0.9300	C19—H19C	0.9600
C7—C8	1.385 (3)	C19—H19D	0.9600
C10—N1—C17	107.95 (17)	H9A—C9—H9B	107.6
C10—N1—C9	126.61 (18)	C11—C10—N1	110.38 (18)
C17—N1—C9	125.33 (17)	C11—C10—H10A	124.8
C1—N2—C8	108.88 (17)	N1—C10—H10A	124.8
C1—N2—H1N2	127.1 (16)	C10—C11—C12	107.10 (19)
C8—N2—H1N2	123.6 (16)	C10—C11—H11A	126.5
C14—O1—C18	117.49 (17)	C12—C11—H11A	126.5
C5—O2—C19	118.1 (2)	C17—C12—C13	119.31 (16)
C2—C1—N2	108.97 (18)	C17—C12—C11	106.74 (18)
C2—C1—C9	129.2 (2)	C13—C12—C11	133.94 (19)
N2—C1—C9	121.79 (19)	C14—C13—C12	118.18 (17)
C1—C2—C3	108.28 (17)	C14—C13—H13A	120.9
C1—C2—H2A	125.9	C12—C13—H13A	120.9
C3—C2—H2A	125.9	C13—C14—O1	124.04 (18)
C8—C3—C4	119.24 (18)	C13—C14—C15	121.81 (18)
C8—C3—C2	106.12 (17)	O1—C14—C15	114.14 (16)
C4—C3—C2	134.64 (18)	C16—C15—C14	120.99 (17)
C5—C4—C3	118.42 (19)	C16—C15—H15A	119.5
C5—C4—H4A	120.8	C14—C15—H15A	119.5
C3—C4—H4A	120.8	C15—C16—C17	117.50 (17)
C4—C5—O2	124.4 (2)	C15—C16—H16A	121.2
C4—C5—C6	121.1 (2)	C17—C16—H16A	121.2
O2—C5—C6	114.5 (2)	N1—C17—C16	129.98 (18)
C7—C6—C5	121.5 (2)	N1—C17—C12	107.83 (16)
C7—C6—H6A	119.3	C16—C17—C12	122.19 (18)
C5—C6—H6A	119.3	O1—C18—H18A	109.5
C6—C7—C8	117.88 (19)	O1—C18—H18B	109.5
C6—C7—H7A	121.1	H18A—C18—H18B	109.5
C8—C7—H7A	121.1	O1—C18—H18C	109.5
N2—C8—C7	130.36 (18)	H18A—C18—H18C	109.5
N2—C8—C3	107.76 (17)	H18B—C18—H18C	109.5
C7—C8—C3	121.86 (19)	O2—C19—H19A	109.5
N1—C9—C1	114.58 (18)	O2—C19—H19C	109.5
N1—C9—H9A	108.6	H19A—C19—H19C	109.5
C1—C9—H9A	108.6	O2—C19—H19D	109.5
N1—C9—H9B	108.6	H19A—C19—H19D	109.5
C1—C9—H9B	108.6	H19C—C19—H19D	109.5
C8—N2—C1—C2	−0.1 (2)	N2—C1—C9—N1	63.6 (3)
C8—N2—C1—C9	178.52 (17)	C17—N1—C10—C11	−0.4 (2)
N2—C1—C2—C3	0.3 (2)	C9—N1—C10—C11	−176.8 (2)
C9—C1—C2—C3	−178.2 (2)	N1—C10—C11—C12	0.0 (3)
C1—C2—C3—C8	−0.3 (2)	C10—C11—C12—C17	0.5 (2)
C1—C2—C3—C4	179.3 (2)	C10—C11—C12—C13	179.3 (2)
C8—C3—C4—C5	−0.7 (3)	C17—C12—C13—C14	1.4 (3)
C2—C3—C4—C5	179.7 (2)	C11—C12—C13—C14	−177.2 (2)
C3—C4—C5—O2	179.0 (2)	C12—C13—C14—O1	177.71 (17)
C3—C4—C5—C6	−1.1 (3)	C12—C13—C14—C15	−1.6 (3)
C19—O2—C5—C4	−17.5 (4)	C18—O1—C14—C13	−2.9 (3)
C19—O2—C5—C6	162.6 (2)	C18—O1—C14—C15	176.4 (2)
C4—C5—C6—C7	1.6 (4)	C13—C14—C15—C16	0.9 (3)
O2—C5—C6—C7	−178.5 (2)	O1—C14—C15—C16	−178.47 (17)
C5—C6—C7—C8	−0.2 (3)	C14—C15—C16—C17	0.0 (3)
C1—N2—C8—C7	178.2 (2)	C10—N1—C17—C16	−178.4 (2)
C1—N2—C8—C3	−0.1 (2)	C9—N1—C17—C16	−1.9 (3)
C6—C7—C8—N2	−179.7 (2)	C10—N1—C17—C12	0.7 (2)
C6—C7—C8—C3	−1.6 (3)	C9—N1—C17—C12	177.15 (18)
C4—C3—C8—N2	−179.48 (17)	C15—C16—C17—N1	178.80 (18)
C2—C3—C8—N2	0.3 (2)	C15—C16—C17—C12	−0.2 (3)
C4—C3—C8—C7	2.1 (3)	C13—C12—C17—N1	−179.73 (16)
C2—C3—C8—C7	−178.18 (18)	C11—C12—C17—N1	−0.7 (2)
C10—N1—C9—C1	−105.6 (2)	C13—C12—C17—C16	−0.5 (3)
C17—N1—C9—C1	78.6 (3)	C11—C12—C17—C16	178.44 (17)
C2—C1—C9—N1	−118.1 (2)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H1N2···O1i	0.88 (2)	2.24 (3)	3.037 (2)	151 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H1N2⋯O1i	0.88 (2)	2.24 (3)	3.037 (2)	151 (2)

Symmetry code: (i) .