1-(1-Hy-droxy-eth-yl)-7,8-dihydro-indolo[2,3-a]pyridine-[3,4-g]quinolizin-5(13H)-one (angustoline) monohydrate from Nauclea subdita (Rubiaceae).

THE TITLE COMPOUND (TRIVIAL NAME: angustoline monohydrate), C(20)H(17)N(3)O(2)·H(2)O, features a fused-ring system formed by one five- and four six-membered rings. The nearly planar benzimidazole portion (r.m.s. deviation = 0.008 Å) and the nearly planar 2,7-naphthyridin-1-one portion (r.m.s. deviation = 0.022 Å) of the fused-ring system are slightly twisted, with a dihedral angle of 9.47 (8)°, owing to the tetra-hedral nature of the two methyl-ene linkages in the central six-membered ring. The secondary N atom acts as a hydrogen-bond donor to the water molecule of crystallization. In the crystal, the amino and hy-droxy groups, and the water mol-ecule are engaged in hydrogen bonding, generating a three-dimensional network.

Related literature

For the isolation of the title compound from other plants, see: Abreu & Pereira (1998 ▶, 2001 ▶); Au et al. (1973 ▶); Carte et al. (1990 ▶); Erdelmeier et al. (1992 ▶); Fan et al. (2010 ▶); Hotellier et al. (1975 ▶); Kakuguchi et al. (2009 ▶); Lin et al. (1988 ▶); Sun et al. (2008 ▶); Xuan et al. (2007 ▶); Zeches et al. (1985 ▶).

Experimental

Crystal data

C20H17N3O2·H2O

M = 349.38

Monoclinic,

a = 8.8350 (3) Å

b = 6.7002 (2) Å

c = 14.7347 (4) Å

β = 103.117 (3)°

V = 849.48 (4) Å3

Z = 2

Cu Kα radiation

μ = 0.76 mm−1

T = 100 K

0.30 × 0.03 × 0.03 mm

Data collection

Agilent SuperNova Dual with an Atlas detector diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T min = 0.803, T max = 0.978

6453 measured reflections

3252 independent reflections

3015 reflections with I > 2σ(I)

R int = 0.027

Refinement

R[F 2 > 2σ(F 2)] = 0.036

wR(F 2) = 0.098

S = 1.02

3252 reflections

251 parameters

1 restraint

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.29 e Å−3

Δρmin = −0.23 e Å−3

Absolute structure: Flack (1983 ▶), 1395 Friedel pairs

Flack parameter: 0.1 (2)

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811022768/xu5242sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811022768/xu5242Isup2.hkl

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

C20H17N3O2·H2O	F(000) = 368
Mr = 349.38	Dx = 1.366 Mg m−3
Monoclinic, P21	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: P 2yb	Cell parameters from 3352 reflections
a = 8.8350 (3) Å	θ = 3.1–74.0°
b = 6.7002 (2) Å	µ = 0.76 mm−1
c = 14.7347 (4) Å	T = 100 K
β = 103.117 (3)°	Prism, yellow
V = 849.48 (4) Å3	0.30 × 0.03 × 0.03 mm
Z = 2

Agilent SuperNova Dual with an Atlas detector diffractometer	3252 independent reflections
Radiation source: SuperNova (Cu) X-ray Source	3015 reflections with I > 2σ(I)
Mirror	Rint = 0.027
Detector resolution: 10.4041 pixels mm-1	θmax = 74.2°, θmin = 3.1°
ω scans	h = −11→9
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	k = −7→8
Tmin = 0.803, Tmax = 0.978	l = −17→18
6453 measured reflections

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)] = 0.036	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.098	w = 1/[σ2(Fo2) + (0.0647P)2 + 0.0395P] where P = (Fo2 + 2Fc2)/3
S = 1.02	(Δ/σ)max = 0.001
3252 reflections	Δρmax = 0.29 e Å−3
251 parameters	Δρmin = −0.23 e Å−3
1 restraint	Absolute structure: Flack (1983), 1395 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: 0.1 (2)

	x	y	z	Uiso*/Ueq
O1	0.33730 (17)	0.5046 (2)	0.78985 (11)	0.0309 (3)
O2	0.76411 (17)	0.6678 (2)	0.44802 (9)	0.0280 (3)
H2	0.677 (4)	0.578 (5)	0.429 (2)	0.061 (9)*
O1W	1.0970 (2)	0.2216 (3)	0.70030 (13)	0.0384 (4)
H11	1.157 (4)	0.316 (6)	0.725 (2)	0.060 (10)*
H12	1.125 (4)	0.196 (6)	0.652 (2)	0.063 (10)*
N1	0.89459 (18)	0.0009 (2)	0.78964 (11)	0.0210 (3)
H1	0.953 (3)	0.071 (4)	0.7637 (15)	0.022 (6)*
N2	0.54310 (19)	0.2982 (2)	0.79266 (12)	0.0234 (3)
N3	0.4603 (2)	0.8811 (3)	0.59777 (12)	0.0280 (4)
C1	0.9248 (2)	−0.1772 (3)	0.83570 (12)	0.0212 (4)
C2	1.0553 (2)	−0.3025 (3)	0.84619 (13)	0.0238 (4)
H2A	1.1403	−0.2694	0.8195	0.029*
C3	1.0547 (2)	−0.4757 (3)	0.89683 (12)	0.0245 (4)
H3	1.1405	−0.5644	0.9040	0.029*
C4	0.9304 (2)	−0.5250 (3)	0.93830 (12)	0.0256 (4)
H4	0.9340	−0.6452	0.9729	0.031*
C5	0.8035 (2)	−0.3999 (3)	0.92892 (12)	0.0236 (4)
H5	0.7204	−0.4328	0.9574	0.028*
C6	0.7989 (2)	−0.2238 (3)	0.87687 (12)	0.0214 (4)
C7	0.6920 (2)	−0.0637 (3)	0.85452 (13)	0.0218 (4)
C8	0.5381 (2)	−0.0264 (3)	0.87749 (14)	0.0250 (4)
H8A	0.5377	−0.0813	0.9398	0.030*
H8B	0.4545	−0.0924	0.8311	0.030*
C9	0.5108 (2)	0.1974 (3)	0.87643 (14)	0.0280 (4)
H9A	0.4015	0.2229	0.8789	0.034*
H9B	0.5781	0.2566	0.9330	0.034*
C10	0.6769 (2)	0.2496 (3)	0.76131 (13)	0.0209 (4)
C11	0.7537 (2)	0.0699 (3)	0.80190 (12)	0.0214 (4)
C12	0.7238 (2)	0.3627 (3)	0.69551 (13)	0.0205 (4)
H12A	0.8131	0.3245	0.6740	0.025*
C13	0.6401 (2)	0.5366 (3)	0.65911 (12)	0.0207 (4)
C14	0.5043 (2)	0.5833 (3)	0.69001 (13)	0.0224 (4)
C15	0.4529 (2)	0.4620 (3)	0.75959 (13)	0.0238 (4)
C16	0.4187 (2)	0.7539 (3)	0.65684 (13)	0.0250 (4)
H16	0.3263	0.7802	0.6775	0.030*
C17	0.5887 (2)	0.8336 (3)	0.56645 (13)	0.0274 (4)
H17	0.6179	0.9220	0.5230	0.033*
C18	0.6799 (2)	0.6681 (3)	0.59251 (12)	0.0230 (4)
C19	0.8136 (2)	0.6270 (3)	0.54537 (13)	0.0260 (4)
H19	0.8421	0.4826	0.5537	0.031*
C20	0.9565 (3)	0.7508 (4)	0.58426 (16)	0.0396 (5)
H20A	1.0380	0.7178	0.5514	0.059*
H20B	0.9938	0.7220	0.6508	0.059*
H20C	0.9306	0.8928	0.5758	0.059*

	U11	U22	U33	U12	U13	U23
O1	0.0278 (7)	0.0272 (7)	0.0445 (8)	0.0050 (6)	0.0228 (6)	0.0025 (6)
O2	0.0305 (7)	0.0321 (7)	0.0238 (7)	−0.0063 (6)	0.0114 (6)	0.0003 (6)
O1W	0.0409 (9)	0.0419 (10)	0.0405 (9)	−0.0122 (7)	0.0261 (7)	−0.0102 (7)
N1	0.0210 (7)	0.0209 (8)	0.0245 (7)	0.0005 (6)	0.0125 (6)	0.0017 (6)
N2	0.0229 (8)	0.0223 (8)	0.0300 (8)	0.0018 (6)	0.0161 (6)	0.0006 (6)
N3	0.0267 (9)	0.0310 (10)	0.0272 (8)	0.0079 (7)	0.0081 (7)	0.0055 (7)
C1	0.0232 (9)	0.0216 (9)	0.0197 (8)	−0.0019 (7)	0.0068 (7)	−0.0023 (7)
C2	0.0233 (9)	0.0278 (10)	0.0222 (8)	0.0038 (7)	0.0089 (7)	−0.0024 (7)
C3	0.0263 (9)	0.0255 (10)	0.0218 (8)	0.0061 (7)	0.0057 (7)	−0.0009 (7)
C4	0.0324 (10)	0.0217 (10)	0.0234 (9)	0.0005 (8)	0.0080 (8)	0.0014 (7)
C5	0.0268 (9)	0.0231 (9)	0.0233 (8)	−0.0033 (8)	0.0107 (7)	−0.0011 (7)
C6	0.0215 (8)	0.0225 (9)	0.0218 (8)	−0.0013 (7)	0.0081 (7)	−0.0036 (7)
C7	0.0232 (9)	0.0207 (9)	0.0243 (8)	−0.0015 (7)	0.0109 (7)	−0.0025 (7)
C8	0.0239 (9)	0.0218 (10)	0.0337 (10)	0.0013 (7)	0.0161 (7)	0.0023 (8)
C9	0.0323 (10)	0.0241 (10)	0.0344 (10)	0.0022 (8)	0.0222 (9)	0.0029 (8)
C10	0.0206 (8)	0.0194 (9)	0.0255 (9)	0.0002 (7)	0.0114 (7)	−0.0032 (7)
C11	0.0218 (8)	0.0205 (9)	0.0248 (8)	0.0004 (7)	0.0112 (7)	−0.0049 (7)
C12	0.0189 (8)	0.0222 (10)	0.0232 (8)	0.0002 (7)	0.0105 (7)	−0.0024 (7)
C13	0.0188 (8)	0.0248 (10)	0.0198 (8)	−0.0010 (7)	0.0070 (7)	−0.0036 (6)
C14	0.0204 (8)	0.0242 (9)	0.0240 (8)	−0.0003 (7)	0.0082 (7)	−0.0011 (7)
C15	0.0224 (9)	0.0214 (10)	0.0305 (9)	0.0003 (7)	0.0122 (7)	−0.0026 (7)
C16	0.0218 (9)	0.0287 (10)	0.0266 (9)	0.0021 (7)	0.0101 (7)	−0.0002 (8)
C17	0.0273 (10)	0.0328 (11)	0.0233 (9)	0.0028 (8)	0.0086 (8)	0.0062 (7)
C18	0.0223 (9)	0.0277 (10)	0.0201 (8)	−0.0006 (7)	0.0073 (7)	−0.0015 (8)
C19	0.0251 (9)	0.0320 (11)	0.0235 (8)	0.0017 (7)	0.0107 (7)	0.0020 (7)
C20	0.0277 (10)	0.0625 (15)	0.0319 (11)	−0.0070 (10)	0.0134 (8)	−0.0115 (10)

O1—C15	1.237 (2)	C7—C11	1.375 (3)
O2—C19	1.428 (2)	C7—C8	1.495 (2)
O2—H2	0.97 (4)	C8—C9	1.518 (3)
O1W—H11	0.85 (4)	C8—H8A	0.9900
O1W—H12	0.83 (4)	C8—H8B	0.9900
N1—C1	1.369 (2)	C9—H9A	0.9900
N1—C11	1.378 (2)	C9—H9B	0.9900
N1—H1	0.85 (3)	C10—C12	1.366 (2)
N2—C15	1.379 (3)	C10—C11	1.443 (3)
N2—C10	1.402 (2)	C12—C13	1.419 (3)
N2—C9	1.490 (2)	C12—H12A	0.9500
N3—C16	1.328 (3)	C13—C14	1.412 (2)
N3—C17	1.356 (3)	C13—C18	1.421 (3)
C1—C2	1.406 (3)	C14—C16	1.396 (3)
C1—C6	1.418 (2)	C14—C15	1.459 (3)
C2—C3	1.380 (3)	C16—H16	0.9500
C2—H2A	0.9500	C17—C18	1.373 (3)
C3—C4	1.412 (3)	C17—H17	0.9500
C3—H3	0.9500	C18—C19	1.525 (2)
C4—C5	1.381 (3)	C19—C20	1.511 (3)
C4—H4	0.9500	C19—H19	1.0000
C5—C6	1.403 (3)	C20—H20A	0.9800
C5—H5	0.9500	C20—H20B	0.9800
C6—C7	1.418 (3)	C20—H20C	0.9800
C19—O2—H2	102.3 (19)	H9A—C9—H9B	107.7
H11—O1W—H12	104 (3)	C12—C10—N2	121.26 (17)
C1—N1—C11	107.94 (15)	C12—C10—C11	124.55 (16)
C1—N1—H1	129.4 (16)	N2—C10—C11	114.15 (15)
C11—N1—H1	122.2 (16)	C7—C11—N1	109.94 (17)
C15—N2—C10	122.12 (15)	C7—C11—C10	124.60 (16)
C15—N2—C9	116.72 (15)	N1—C11—C10	125.37 (16)
C10—N2—C9	120.11 (16)	C10—C12—C13	120.54 (16)
C16—N3—C17	116.71 (17)	C10—C12—H12A	119.7
N1—C1—C2	129.66 (17)	C13—C12—H12A	119.7
N1—C1—C6	108.67 (16)	C14—C13—C12	117.92 (16)
C2—C1—C6	121.66 (17)	C14—C13—C18	116.52 (17)
C3—C2—C1	117.27 (17)	C12—C13—C18	125.56 (16)
C3—C2—H2A	121.4	C16—C14—C13	120.08 (16)
C1—C2—H2A	121.4	C16—C14—C15	118.13 (16)
C2—C3—C4	121.95 (17)	C13—C14—C15	121.74 (17)
C2—C3—H3	119.0	O1—C15—N2	120.96 (17)
C4—C3—H3	119.0	O1—C15—C14	122.63 (18)
C5—C4—C3	120.55 (18)	N2—C15—C14	116.38 (16)
C5—C4—H4	119.7	N3—C16—C14	123.12 (16)
C3—C4—H4	119.7	N3—C16—H16	118.4
C4—C5—C6	119.14 (17)	C14—C16—H16	118.4
C4—C5—H5	120.4	N3—C17—C18	125.27 (19)
C6—C5—H5	120.4	N3—C17—H17	117.4
C5—C6—C1	119.41 (17)	C18—C17—H17	117.4
C5—C6—C7	134.32 (17)	C17—C18—C13	118.21 (17)
C1—C6—C7	106.26 (16)	C17—C18—C19	118.98 (17)
C11—C7—C6	107.19 (16)	C13—C18—C19	122.73 (17)
C11—C7—C8	121.06 (17)	O2—C19—C20	108.34 (17)
C6—C7—C8	131.75 (17)	O2—C19—C18	109.32 (16)
C7—C8—C9	108.24 (15)	C20—C19—C18	113.28 (16)
C7—C8—H8A	110.1	O2—C19—H19	108.6
C9—C8—H8A	110.1	C20—C19—H19	108.6
C7—C8—H8B	110.1	C18—C19—H19	108.6
C9—C8—H8B	110.1	C19—C20—H20A	109.5
H8A—C8—H8B	108.4	C19—C20—H20B	109.5
N2—C9—C8	113.37 (16)	H20A—C20—H20B	109.5
N2—C9—H9A	108.9	C19—C20—H20C	109.5
C8—C9—H9A	108.9	H20A—C20—H20C	109.5
N2—C9—H9B	108.9	H20B—C20—H20C	109.5
C8—C9—H9B	108.9
C11—N1—C1—C2	−177.98 (19)	N2—C10—C11—C7	10.4 (3)
C11—N1—C1—C6	0.94 (19)	C12—C10—C11—N1	8.9 (3)
N1—C1—C2—C3	−179.93 (17)	N2—C10—C11—N1	−173.35 (17)
C6—C1—C2—C3	1.3 (3)	N2—C10—C12—C13	1.9 (3)
C1—C2—C3—C4	−1.2 (3)	C11—C10—C12—C13	179.54 (17)
C2—C3—C4—C5	0.3 (3)	C10—C12—C13—C14	−2.7 (3)
C3—C4—C5—C6	0.6 (3)	C10—C12—C13—C18	178.32 (18)
C4—C5—C6—C1	−0.5 (3)	C12—C13—C14—C16	179.44 (17)
C4—C5—C6—C7	−178.7 (2)	C18—C13—C14—C16	−1.5 (3)
N1—C1—C6—C5	−179.48 (16)	C12—C13—C14—C15	2.1 (3)
C2—C1—C6—C5	−0.5 (3)	C18—C13—C14—C15	−178.81 (17)
N1—C1—C6—C7	−0.8 (2)	C10—N2—C15—O1	−178.32 (18)
C2—C1—C6—C7	178.23 (17)	C9—N2—C15—O1	−10.0 (3)
C5—C6—C7—C11	178.7 (2)	C10—N2—C15—C14	−0.1 (3)
C1—C6—C7—C11	0.3 (2)	C9—N2—C15—C14	168.16 (17)
C5—C6—C7—C8	−1.8 (4)	C16—C14—C15—O1	0.0 (3)
C1—C6—C7—C8	179.82 (19)	C13—C14—C15—O1	177.41 (18)
C11—C7—C8—C9	−26.5 (3)	C16—C14—C15—N2	−178.11 (18)
C6—C7—C8—C9	154.1 (2)	C13—C14—C15—N2	−0.7 (3)
C15—N2—C9—C8	147.19 (18)	C17—N3—C16—C14	3.0 (3)
C10—N2—C9—C8	−44.3 (3)	C13—C14—C16—N3	−1.6 (3)
C7—C8—C9—N2	47.4 (2)	C15—C14—C16—N3	175.87 (18)
C15—N2—C10—C12	−0.5 (3)	C16—N3—C17—C18	−1.5 (3)
C9—N2—C10—C12	−168.38 (18)	N3—C17—C18—C13	−1.4 (3)
C15—N2—C10—C11	−178.32 (17)	N3—C17—C18—C19	175.34 (19)
C9—N2—C10—C11	13.8 (2)	C14—C13—C18—C17	2.8 (3)
C6—C7—C11—N1	0.2 (2)	C12—C13—C18—C17	−178.17 (18)
C8—C7—C11—N1	−179.32 (17)	C14—C13—C18—C19	−173.81 (17)
C6—C7—C11—C10	176.94 (17)	C12—C13—C18—C19	5.2 (3)
C8—C7—C11—C10	−2.6 (3)	C17—C18—C19—O2	−41.1 (2)
C1—N1—C11—C7	−0.7 (2)	C13—C18—C19—O2	135.53 (18)
C1—N1—C11—C10	−177.41 (17)	C17—C18—C19—C20	79.8 (2)
C12—C10—C11—C7	−167.33 (19)	C13—C18—C19—C20	−103.6 (2)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N3i	0.97 (4)	1.77 (4)	2.732 (2)	171 (3)
O1w—H11···O1ii	0.85 (4)	2.08 (4)	2.928 (2)	169 (3)
O1w—H12···O2iii	0.83 (4)	1.95 (4)	2.762 (2)	167 (3)
N1—H1···O1w	0.85 (3)	2.02 (3)	2.861 (2)	177 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯N3i	0.97 (4)	1.77 (4)	2.732 (2)	171 (3)
O1w—H11⋯O1ii	0.85 (4)	2.08 (4)	2.928 (2)	169 (3)
O1w—H12⋯O2iii	0.83 (4)	1.95 (4)	2.762 (2)	167 (3)
N1—H1⋯O1w	0.85 (3)	2.02 (3)	2.861 (2)	177 (2)

Symmetry codes: (i) ; (ii) ; (iii) .