organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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10-Allyl-2,3-di­hydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11(10H,11aH)-dione

aLaboratoire de Chimie Organique Hétérocyclique, Pôle de compétences Pharmacochimie, Université Mohammed V-Agdal, BP 1014 Avenue Ibn Batout, Rabat, Morocco, bService commun Rayons X, Université Paul Sabatier, Bâtiment 2R1, 118 route de Narbonne, 31062 Toulouse, France, cHétérochimie Fondamentale et Appliquée, Université Paul Sabatier, UMR 5069, 118 Route de Narbonne, 31062 Toulouse, France, and dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my

(Received 24 August 2009; accepted 27 August 2009; online 5 September 2009)

The compound, C15H16N2O2, features a pyrroline ring fused with a seven-membered diazepine ring; the latter system adopts a boat conformation (with the methine C atom as the prow and the two C atoms of the aromatic ring as the stern). A CH2–CH2 segment of the pyrroline ring is disordered over two positions in a 1:1 ratio.

Related literature

Pyrrolo[2,1-c][1,4]benzodiazepines are potent, naturally occurring anti­tumor anti­biotics produced by Streptomyces species; see: Cargill et al. (1974[Cargill, C., Bachmann, E. & Zbinden, G. (1974). J. Natl. Cancer Inst. 53, 481-486.]); Thurston et al. (1993[Thurston, D. E., Neidle, S. & Waring, M. J. (1993). Molecular Aspects of Anticancer Drug-DNA Interactions, Vol. 1, pp. 54-88. New York: Macmillan Press.]). For the design and synthesis of DNA inter-strand cross-linking as well as conjugate agents to enhance the sequence selectivity and to increase selectivity for tumor cells, see: Bose et al. (1992[Bose, D. S., Thompson, A. S., Ching, J. A., Hartley, J. A., Berardini, M. D., Jenkins, T. C., Neidle, S., Hurley, L. H. & Thurston, D. E. (1992). J. Am. Chem. Soc. 114, 4939-4941.]); Gregson et al. (2004[Gregson, S. T., Howard, P. W., Gullick, D. R., Hamaguchi, A., Corcoran, K. E., Brooks, N. A., Hartley, J. A., Jenkins, T. C., Patel, S., Guille, M. J. & Thurston, D. E. (2004). J. Med. Chem. 47, 1161-1174.]).

[Scheme 1]

Experimental

Crystal data
  • C15H16N2O2

  • Mr = 256.30

  • Orthorhombic, P 21 21 21

  • a = 7.0988 (1) Å

  • b = 11.7166 (2) Å

  • c = 15.6592 (3) Å

  • V = 1302.44 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 193 K

  • 0.30 × 0.30 × 0.20 mm

Data collection
  • Bruker APEXII diffractometer

  • Absorption correction: none

  • 20329 measured reflections

  • 2263 independent reflections

  • 1900 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.146

  • S = 1.04

  • 2263 reflections

  • 178 parameters

  • 15 restraints

  • H-atom parameters constrained

  • Δρmax = 0.53 e Å−3

  • Δρmin = −0.30 e Å−3

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]); software used to prepare material for publication: publCIF (Westrip, 2009[Westrip, S. P. (2009). publCIF. In preparation.]).

Supporting information


Related literature top

Pyrrolo[2,1-c][1,4]benzodiazepines are potent, naturally occurring antitumor antibiotics produced by Streptomyces species; see: Cargill et al. (1974); Thurston et al. (1993). For the design and synthesis of DNA inter-strand cross-linking as well as conjugate agents to enhance the sequence selectivity and to increase selectivity for tumor cells, see: Bose et al. (1992); Gregson et al. (2004).

Experimental top

2,3-Dihydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11(10H,11aH)-dione (1 g, 4.6 mmol), allyl bromide (0.64 g, 4.6 mmol) and potassium carbonate (0.64 g, 4.6 mmol) along with a catalytic amount of tetra-n-butyammonium bromide were stirred in N,N-dimethylformamide (20 ml) for 12 h. After the completion of the reaction (as monitored by TLC), the solid material was removed by filtration and the solvent evaporated under vacuum. Dichloromethane (20 ml) was added and the solution filtered. The solvent was removed and the product purified by recrystallization from dichloromethane to afford colorless crystals in 80% yield. The formulation was established by proton and carbon-13 NMR spectroscopy in CDCl3.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 to 0.99 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2U(C).

Two of the carbon atoms in the tetrahydropyrrolyl ring are disordered over two positions; the occupancy cound not be refined, and was assumed to be 50:50. The pairs of carbon-carbon (C10–C11, C10'–C11') distances were restrained to within 0.01 Å of each other, and the temperature factors of the primed atoms were restrained to those of the unprimed ones. Their anisotropic temperature factors were restrained to nearly isotropic values.

In the absence of significant anomalous dispersion effects, Freidel pairs were merged.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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, 2009).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C15H16N2O2 at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.
10-Allyl-2,3-dihydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11(10H,11aH)-dione top
Crystal data top
C15H16N2O2F(000) = 544
Mr = 256.30Dx = 1.307 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 7433 reflections
a = 7.0988 (1) Åθ = 2.2–25.3°
b = 11.7166 (2) ŵ = 0.09 mm1
c = 15.6592 (3) ÅT = 193 K
V = 1302.44 (4) Å3Block, colorless
Z = 40.30 × 0.30 × 0.20 mm
Data collection top
Bruker APEXII
diffractometer
1900 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 30.5°, θmin = 5.2°
ϕ and ω scansh = 1010
20329 measured reflectionsk = 1614
2263 independent reflectionsl = 2219
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.146H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.086P)2 + 0.2922P]
where P = (Fo2 + 2Fc2)/3
2263 reflections(Δ/σ)max = 0.001
178 parametersΔρmax = 0.53 e Å3
15 restraintsΔρmin = 0.30 e Å3
Crystal data top
C15H16N2O2V = 1302.44 (4) Å3
Mr = 256.30Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.0988 (1) ŵ = 0.09 mm1
b = 11.7166 (2) ÅT = 193 K
c = 15.6592 (3) Å0.30 × 0.30 × 0.20 mm
Data collection top
Bruker APEXII
diffractometer
1900 reflections with I > 2σ(I)
20329 measured reflectionsRint = 0.031
2263 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.04915 restraints
wR(F2) = 0.146H-atom parameters constrained
S = 1.04Δρmax = 0.53 e Å3
2263 reflectionsΔρmin = 0.30 e Å3
178 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.3349 (3)0.89582 (17)0.62000 (12)0.0545 (5)
O20.1387 (3)0.62142 (13)0.76109 (11)0.0423 (4)
N10.2785 (2)0.86934 (15)0.76059 (12)0.0312 (4)
N20.0624 (3)0.77145 (15)0.67775 (12)0.0327 (4)
C10.2213 (4)0.88657 (18)0.67841 (15)0.0355 (5)
C20.0695 (3)0.71719 (17)0.75353 (14)0.0301 (4)
C30.0008 (3)0.78280 (17)0.82960 (13)0.0280 (4)
C40.1542 (3)0.85792 (16)0.83096 (13)0.0279 (4)
C50.1940 (3)0.91758 (17)0.90646 (13)0.0333 (4)
H50.29890.96780.90830.040*
C60.0828 (4)0.9044 (2)0.97834 (14)0.0396 (5)
H60.10900.94761.02830.048*
C70.0675 (4)0.8278 (2)0.97772 (14)0.0407 (5)
H70.14250.81721.02740.049*
C80.1059 (3)0.76768 (19)0.90409 (14)0.0359 (5)
H80.20690.71440.90400.043*
C90.1524 (4)0.7262 (2)0.60032 (14)0.0399 (5)
H9A0.26780.68230.61370.048*0.50
H9B0.06510.67800.56670.048*0.50
H9C0.27590.69160.61430.048*0.50
H9D0.07190.66710.57360.048*0.50
C100.197 (3)0.8367 (11)0.5551 (12)0.059 (3)0.50
H10A0.21870.82360.49350.071*0.50
H10B0.31020.87320.58000.071*0.50
C110.025 (2)0.9097 (17)0.5692 (5)0.047 (2)0.50
H11A0.05000.99120.55700.056*0.50
H11B0.08320.88350.53420.056*0.50
C10'0.178 (3)0.8258 (11)0.5408 (12)0.059 (3)0.50
H10C0.31240.84650.53660.071*0.50
H10D0.13120.80610.48300.071*0.50
C11'0.066 (2)0.9241 (16)0.5769 (5)0.047 (2)0.50
H11C0.14750.99230.58230.056*0.50
H11D0.04000.94300.53840.056*0.50
C120.0096 (3)0.88869 (18)0.66551 (14)0.0339 (5)
H120.05510.94590.70270.041*0.50
H12'0.04790.93940.70980.041*0.50
C130.4837 (3)0.8775 (2)0.77691 (19)0.0433 (6)
H13A0.55220.83220.73350.052*
H13B0.51210.84460.83370.052*
C140.5520 (4)1.0005 (2)0.7740 (2)0.0490 (6)
H140.50201.04900.73090.059*
C150.6751 (4)1.0438 (3)0.8269 (2)0.0565 (7)
H15A0.72780.99760.87070.068*
H15B0.71191.12140.82160.068*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0621 (12)0.0550 (11)0.0466 (10)0.0140 (10)0.0231 (9)0.0031 (9)
O20.0473 (9)0.0272 (7)0.0525 (10)0.0097 (7)0.0042 (8)0.0039 (7)
N10.0253 (7)0.0269 (8)0.0413 (10)0.0014 (6)0.0036 (7)0.0012 (7)
N20.0361 (8)0.0276 (8)0.0345 (8)0.0072 (7)0.0013 (8)0.0020 (7)
C10.0425 (11)0.0278 (9)0.0362 (10)0.0075 (9)0.0072 (9)0.0012 (8)
C20.0273 (8)0.0252 (8)0.0380 (10)0.0003 (7)0.0003 (9)0.0007 (8)
C30.0266 (8)0.0245 (8)0.0331 (9)0.0012 (7)0.0001 (8)0.0042 (7)
C40.0267 (8)0.0225 (8)0.0345 (9)0.0010 (7)0.0026 (8)0.0043 (7)
C50.0358 (10)0.0277 (9)0.0362 (10)0.0004 (8)0.0083 (9)0.0034 (8)
C60.0487 (13)0.0388 (11)0.0312 (10)0.0040 (10)0.0062 (10)0.0022 (9)
C70.0467 (12)0.0436 (12)0.0320 (10)0.0029 (11)0.0042 (10)0.0098 (9)
C80.0345 (10)0.0360 (10)0.0372 (10)0.0027 (9)0.0015 (9)0.0095 (9)
C90.0446 (12)0.0394 (11)0.0357 (11)0.0074 (10)0.0010 (10)0.0097 (9)
C100.088 (4)0.059 (3)0.031 (5)0.015 (3)0.015 (4)0.000 (3)
C110.061 (6)0.042 (4)0.0371 (16)0.008 (4)0.012 (3)0.010 (2)
C10'0.088 (4)0.059 (3)0.031 (5)0.015 (3)0.015 (4)0.000 (3)
C11'0.061 (6)0.042 (4)0.0371 (16)0.008 (4)0.012 (3)0.010 (2)
C120.0440 (11)0.0259 (9)0.0319 (10)0.0067 (9)0.0066 (9)0.0041 (8)
C130.0253 (9)0.0403 (12)0.0643 (16)0.0012 (9)0.0044 (10)0.0007 (11)
C140.0315 (11)0.0506 (14)0.0648 (16)0.0065 (11)0.0037 (12)0.0040 (13)
C150.0413 (13)0.0502 (14)0.078 (2)0.0061 (12)0.0002 (15)0.0023 (14)
Geometric parameters (Å, º) top
O1—C11.224 (3)C9—H9C0.9900
O2—C21.231 (3)C9—H9D0.9900
N1—C11.365 (3)C10—C111.509 (9)
N1—C41.418 (3)C10—H10A0.9900
N1—C131.482 (3)C10—H10B0.9900
N2—C21.347 (3)C11—C121.547 (6)
N2—C91.470 (3)C11—H11A0.9900
N2—C121.478 (3)C11—H11B0.9900
C1—C121.517 (4)C10'—C11'1.507 (9)
C2—C31.499 (3)C10'—H10C0.9900
C3—C81.396 (3)C10'—H10D0.9900
C3—C41.409 (3)C11'—C121.545 (6)
C4—C51.402 (3)C11'—H11C0.9900
C5—C61.383 (3)C11'—H11D0.9900
C5—H50.9500C12—H121.0000
C6—C71.395 (4)C12—H12'1.0000
C6—H60.9500C13—C141.522 (3)
C7—C81.378 (3)C13—H13A0.9900
C7—H70.9500C13—H13B0.9900
C8—H80.9500C14—C151.306 (4)
C9—C10'1.504 (7)C14—H140.9500
C9—C101.510 (7)C15—H15A0.9500
C9—H9A0.9900C15—H15B0.9500
C9—H9B0.9900
C1—N1—C4124.17 (18)C11—C10—H10A110.9
C1—N1—C13116.5 (2)C9—C10—H10A110.9
C4—N1—C13118.9 (2)C11—C10—H10B110.9
C2—N2—C9122.70 (18)C9—C10—H10B110.9
C2—N2—C12124.44 (18)H10A—C10—H10B108.9
C9—N2—C12112.27 (18)C10—C11—C12100.3 (12)
O1—C1—N1121.5 (2)C10—C11—H11A111.7
O1—C1—C12123.5 (2)C12—C11—H11A111.7
N1—C1—C12115.02 (19)C10—C11—H11B111.7
O2—C2—N2122.0 (2)C12—C11—H11B111.7
O2—C2—C3121.4 (2)H11A—C11—H11B109.5
N2—C2—C3116.48 (18)C9—C10'—C11'107.4 (12)
C8—C3—C4118.96 (19)C9—C10'—H10C110.2
C8—C3—C2115.13 (18)C11'—C10'—H10C110.2
C4—C3—C2125.89 (18)C9—C10'—H10D110.2
C5—C4—C3118.78 (19)C11'—C10'—H10D110.2
C5—C4—N1118.87 (18)H10C—C10'—H10D108.5
C3—C4—N1122.21 (18)C10'—C11'—C12108.3 (12)
C6—C5—C4121.0 (2)C10'—C11'—H11C110.0
C6—C5—H5119.5C12—C11'—H11C110.0
C4—C5—H5119.5C10'—C11'—H11D110.0
C5—C6—C7120.2 (2)C12—C11'—H11D110.0
C5—C6—H6119.9H11C—C11'—H11D108.4
C7—C6—H6119.9N2—C12—C1108.08 (19)
C8—C7—C6119.1 (2)N2—C12—C11'104.2 (8)
C8—C7—H7120.5C1—C12—C11'117.9 (7)
C6—C7—H7120.5N2—C12—C11102.7 (8)
C7—C8—C3121.9 (2)C1—C12—C11106.7 (6)
C7—C8—H8119.1N2—C12—H12112.9
C3—C8—H8119.1C1—C12—H12112.9
N2—C9—C10'106.4 (8)C11'—C12—H12100.6
N2—C9—C1099.7 (8)C11—C12—H12112.9
N2—C9—H9A111.8N2—C12—H12'108.8
C10'—C9—H9A115.9C1—C12—H12'108.8
C10—C9—H9A111.8C11'—C12—H12'108.8
N2—C9—H9B111.8C11—C12—H12'121.1
C10'—C9—H9B100.8N1—C13—C14111.7 (2)
C10—C9—H9B111.8N1—C13—H13A109.3
H9A—C9—H9B109.6C14—C13—H13A109.3
N2—C9—H9C110.5N1—C13—H13B109.3
C10'—C9—H9C110.5C14—C13—H13B109.3
C10—C9—H9C105.6H13A—C13—H13B108.0
H9B—C9—H9C116.1C15—C14—C13124.2 (3)
N2—C9—H9D110.5C15—C14—H14117.9
C10'—C9—H9D110.5C13—C14—H14117.9
C10—C9—H9D121.5C14—C15—H15A120.0
H9A—C9—H9D101.8C14—C15—H15B120.0
H9C—C9—H9D108.6H15A—C15—H15B120.0
C11—C10—C9104.3 (14)
C4—N1—C1—O1180.0 (2)C2—N2—C9—C10150.1 (10)
C13—N1—C1—O17.7 (3)C12—N2—C9—C1021.4 (10)
C4—N1—C1—C122.2 (3)N2—C9—C10—C1141.2 (14)
C13—N1—C1—C12174.50 (19)C10'—C9—C10—C1187 (8)
C9—N2—C2—O26.1 (3)C9—C10—C11—C1245.3 (16)
C12—N2—C2—O2176.6 (2)N2—C9—C10'—C11'11.4 (17)
C9—N2—C2—C3169.74 (19)C10—C9—C10'—C11'65 (8)
C12—N2—C2—C30.8 (3)C9—C10'—C11'—C126.8 (19)
O2—C2—C3—C835.3 (3)C2—N2—C12—C170.3 (3)
N2—C2—C3—C8140.6 (2)C9—N2—C12—C1118.3 (2)
O2—C2—C3—C4146.2 (2)C2—N2—C12—C11'163.4 (7)
N2—C2—C3—C438.0 (3)C9—N2—C12—C11'7.9 (7)
C8—C3—C4—C51.9 (3)C2—N2—C12—C11177.1 (6)
C2—C3—C4—C5176.60 (19)C9—N2—C12—C115.7 (6)
C8—C3—C4—N1173.72 (18)O1—C1—C12—N2107.3 (3)
C2—C3—C4—N17.8 (3)N1—C1—C12—N270.5 (3)
C1—N1—C4—C5134.8 (2)O1—C1—C12—C11'10.4 (9)
C13—N1—C4—C537.4 (3)N1—C1—C12—C11'171.8 (8)
C1—N1—C4—C349.6 (3)O1—C1—C12—C112.6 (8)
C13—N1—C4—C3138.2 (2)N1—C1—C12—C11179.7 (8)
C3—C4—C5—C60.7 (3)C10'—C11'—C12—N20.5 (14)
N1—C4—C5—C6176.43 (19)C10'—C11'—C12—C1119.3 (11)
C4—C5—C6—C72.4 (3)C10'—C11'—C12—C1185 (7)
C5—C6—C7—C81.4 (4)C10—C11—C12—N230.4 (12)
C6—C7—C8—C31.2 (4)C10—C11—C12—C1144.0 (10)
C4—C3—C8—C72.9 (3)C10—C11—C12—C11'68 (6)
C2—C3—C8—C7175.8 (2)C1—N1—C13—C1473.4 (3)
C2—N2—C9—C10'159.3 (10)C4—N1—C13—C1499.4 (3)
C12—N2—C9—C10'12.3 (10)N1—C13—C14—C15139.5 (3)

Experimental details

Crystal data
Chemical formulaC15H16N2O2
Mr256.30
Crystal system, space groupOrthorhombic, P212121
Temperature (K)193
a, b, c (Å)7.0988 (1), 11.7166 (2), 15.6592 (3)
V3)1302.44 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.30 × 0.30 × 0.20
Data collection
DiffractometerBruker APEXII
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
20329, 2263, 1900
Rint0.031
(sin θ/λ)max1)0.714
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.146, 1.04
No. of reflections2263
No. of parameters178
No. of restraints15
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.53, 0.30

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

 

Acknowledgements

We thank Université Mohammed V-Agdal and the University of Malaya for supporting this study.

References

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