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

Benzeid, H.; Essassi, E.M.; Saffon, N.; Garrigues, B.; Ng, S.W.

doi:10.1107/S1600536809034266

organic compounds

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ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page o2322

doi:10.1107/S1600536809034266

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

Hanane Benzeid,^a El Mokhtar Essassi,^a Nathalie Saffon,^b Bernard Garrigues ^c and Seik Weng Ng ^d ^*

^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 ); 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

Crystal data

C₁₅H₁₆N₂O₂
M_r = 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)
R_int = 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
Δρ_max = 0.53 e Å⁻³
Δρ_min = −0.30 e Å⁻³

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

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809034266/sj2637sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809034266/sj2637Isup2.hkl

checkCIF report

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.

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

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

C₁₅H₁₆N₂O₂	F(000) = 544
M_r = 256.30	D_x = 1.307 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 7433 reflections
a = 7.0988 (1) Å	θ = 2.2–25.3°
b = 11.7166 (2) Å	µ = 0.09 mm⁻¹
c = 15.6592 (3) Å	T = 193 K
V = 1302.44 (4) Å³	Block, colorless
Z = 4	0.30 × 0.30 × 0.20 mm

Data collection top

Bruker APEXII diffractometer	1900 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.031
Graphite monochromator	θ_max = 30.5°, θ_min = 5.2°
ϕ and ω scans	h = −10→10
20329 measured reflections	k = −16→14
2263 independent reflections	l = −22→19

Refinement top

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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.146	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.086P)² + 0.2922P] where P = (F_o² + 2F_c²)/3
2263 reflections	(Δ/σ)_max = 0.001
178 parameters	Δρ_max = 0.53 e Å⁻³
15 restraints	Δρ_min = −0.30 e Å⁻³

Crystal data top

C₁₅H₁₆N₂O₂	V = 1302.44 (4) Å³
M_r = 256.30	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.0988 (1) Å	µ = 0.09 mm⁻¹
b = 11.7166 (2) Å	T = 193 K
c = 15.6592 (3) Å	0.30 × 0.30 × 0.20 mm

Data collection top

Bruker APEXII diffractometer	1900 reflections with I > 2σ(I)
20329 measured reflections	R_int = 0.031
2263 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	15 restraints
wR(F²) = 0.146	H-atom parameters constrained
S = 1.04	Δρ_max = 0.53 e Å⁻³
2263 reflections	Δρ_min = −0.30 e Å⁻³
178 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O1	0.3349 (3)	0.89582 (17)	0.62000 (12)	0.0545 (5)
O2	−0.1387 (3)	0.62142 (13)	0.76109 (11)	0.0423 (4)
N1	0.2785 (2)	0.86934 (15)	0.76059 (12)	0.0312 (4)
N2	−0.0624 (3)	0.77145 (15)	0.67775 (12)	0.0327 (4)
C1	0.2213 (4)	0.88657 (18)	0.67841 (15)	0.0355 (5)
C2	−0.0695 (3)	0.71719 (17)	0.75353 (14)	0.0301 (4)
C3	−0.0008 (3)	0.78280 (17)	0.82960 (13)	0.0280 (4)
C4	0.1542 (3)	0.85792 (16)	0.83096 (13)	0.0279 (4)
C5	0.1940 (3)	0.91758 (17)	0.90646 (13)	0.0333 (4)
H5	0.2989	0.9678	0.9083	0.040*
C6	0.0828 (4)	0.9044 (2)	0.97834 (14)	0.0396 (5)
H6	0.1090	0.9476	1.0283	0.048*
C7	−0.0675 (4)	0.8278 (2)	0.97772 (14)	0.0407 (5)
H7	−0.1425	0.8172	1.0274	0.049*
C8	−0.1059 (3)	0.76768 (19)	0.90409 (14)	0.0359 (5)
H8	−0.2069	0.7144	0.9040	0.043*
C9	−0.1524 (4)	0.7262 (2)	0.60032 (14)	0.0399 (5)
H9A	−0.2678	0.6823	0.6137	0.048*	0.50
H9B	−0.0651	0.6780	0.5667	0.048*	0.50
H9C	−0.2759	0.6916	0.6143	0.048*	0.50
H9D	−0.0719	0.6671	0.5736	0.048*	0.50
C10	−0.197 (3)	0.8367 (11)	0.5551 (12)	0.059 (3)	0.50
H10A	−0.2187	0.8236	0.4935	0.071*	0.50
H10B	−0.3102	0.8732	0.5800	0.071*	0.50
C11	−0.025 (2)	0.9097 (17)	0.5692 (5)	0.047 (2)	0.50
H11A	−0.0500	0.9912	0.5570	0.056*	0.50
H11B	0.0832	0.8835	0.5342	0.056*	0.50
C10'	−0.178 (3)	0.8258 (11)	0.5408 (12)	0.059 (3)	0.50
H10C	−0.3124	0.8465	0.5366	0.071*	0.50
H10D	−0.1312	0.8061	0.4830	0.071*	0.50
C11'	−0.066 (2)	0.9241 (16)	0.5769 (5)	0.047 (2)	0.50
H11C	−0.1475	0.9923	0.5823	0.056*	0.50
H11D	0.0400	0.9430	0.5384	0.056*	0.50
C12	0.0096 (3)	0.88869 (18)	0.66551 (14)	0.0339 (5)
H12	−0.0551	0.9459	0.7027	0.041*	0.50
H12'	−0.0479	0.9394	0.7098	0.041*	0.50
C13	0.4837 (3)	0.8775 (2)	0.77691 (19)	0.0433 (6)
H13A	0.5522	0.8322	0.7335	0.052*
H13B	0.5121	0.8446	0.8337	0.052*
C14	0.5520 (4)	1.0005 (2)	0.7740 (2)	0.0490 (6)
H14	0.5020	1.0490	0.7309	0.059*
C15	0.6751 (4)	1.0438 (3)	0.8269 (2)	0.0565 (7)
H15A	0.7278	0.9976	0.8707	0.068*
H15B	0.7119	1.1214	0.8216	0.068*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0621 (12)	0.0550 (11)	0.0466 (10)	−0.0140 (10)	0.0231 (9)	−0.0031 (9)
O2	0.0473 (9)	0.0272 (7)	0.0525 (10)	−0.0097 (7)	−0.0042 (8)	0.0039 (7)
N1	0.0253 (7)	0.0269 (8)	0.0413 (10)	−0.0014 (6)	0.0036 (7)	0.0012 (7)
N2	0.0361 (8)	0.0276 (8)	0.0345 (8)	−0.0072 (7)	−0.0013 (8)	−0.0020 (7)
C1	0.0425 (11)	0.0278 (9)	0.0362 (10)	−0.0075 (9)	0.0072 (9)	−0.0012 (8)
C2	0.0273 (8)	0.0252 (8)	0.0380 (10)	−0.0003 (7)	0.0003 (9)	0.0007 (8)
C3	0.0266 (8)	0.0245 (8)	0.0331 (9)	0.0012 (7)	−0.0001 (8)	0.0042 (7)
C4	0.0267 (8)	0.0225 (8)	0.0345 (9)	0.0010 (7)	−0.0026 (8)	0.0043 (7)
C5	0.0358 (10)	0.0277 (9)	0.0362 (10)	−0.0004 (8)	−0.0083 (9)	0.0034 (8)
C6	0.0487 (13)	0.0388 (11)	0.0312 (10)	0.0040 (10)	−0.0062 (10)	0.0022 (9)
C7	0.0467 (12)	0.0436 (12)	0.0320 (10)	0.0029 (11)	0.0042 (10)	0.0098 (9)
C8	0.0345 (10)	0.0360 (10)	0.0372 (10)	−0.0027 (9)	0.0015 (9)	0.0095 (9)
C9	0.0446 (12)	0.0394 (11)	0.0357 (11)	−0.0074 (10)	−0.0010 (10)	−0.0097 (9)
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)
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)
C12	0.0440 (11)	0.0259 (9)	0.0319 (10)	−0.0067 (9)	−0.0066 (9)	0.0041 (8)
C13	0.0253 (9)	0.0403 (12)	0.0643 (16)	0.0012 (9)	0.0044 (10)	−0.0007 (11)
C14	0.0315 (11)	0.0506 (14)	0.0648 (16)	−0.0065 (11)	0.0037 (12)	0.0040 (13)
C15	0.0413 (13)	0.0502 (14)	0.078 (2)	−0.0061 (12)	0.0002 (15)	−0.0023 (14)

Geometric parameters (Å, º) top

O1—C1	1.224 (3)	C9—H9C	0.9900
O2—C2	1.231 (3)	C9—H9D	0.9900
N1—C1	1.365 (3)	C10—C11	1.509 (9)
N1—C4	1.418 (3)	C10—H10A	0.9900
N1—C13	1.482 (3)	C10—H10B	0.9900
N2—C2	1.347 (3)	C11—C12	1.547 (6)
N2—C9	1.470 (3)	C11—H11A	0.9900
N2—C12	1.478 (3)	C11—H11B	0.9900
C1—C12	1.517 (4)	C10'—C11'	1.507 (9)
C2—C3	1.499 (3)	C10'—H10C	0.9900
C3—C8	1.396 (3)	C10'—H10D	0.9900
C3—C4	1.409 (3)	C11'—C12	1.545 (6)
C4—C5	1.402 (3)	C11'—H11C	0.9900
C5—C6	1.383 (3)	C11'—H11D	0.9900
C5—H5	0.9500	C12—H12	1.0000
C6—C7	1.395 (4)	C12—H12'	1.0000
C6—H6	0.9500	C13—C14	1.522 (3)
C7—C8	1.378 (3)	C13—H13A	0.9900
C7—H7	0.9500	C13—H13B	0.9900
C8—H8	0.9500	C14—C15	1.306 (4)
C9—C10'	1.504 (7)	C14—H14	0.9500
C9—C10	1.510 (7)	C15—H15A	0.9500
C9—H9A	0.9900	C15—H15B	0.9500
C9—H9B	0.9900

C1—N1—C4	124.17 (18)	C11—C10—H10A	110.9
C1—N1—C13	116.5 (2)	C9—C10—H10A	110.9
C4—N1—C13	118.9 (2)	C11—C10—H10B	110.9
C2—N2—C9	122.70 (18)	C9—C10—H10B	110.9
C2—N2—C12	124.44 (18)	H10A—C10—H10B	108.9
C9—N2—C12	112.27 (18)	C10—C11—C12	100.3 (12)
O1—C1—N1	121.5 (2)	C10—C11—H11A	111.7
O1—C1—C12	123.5 (2)	C12—C11—H11A	111.7
N1—C1—C12	115.02 (19)	C10—C11—H11B	111.7
O2—C2—N2	122.0 (2)	C12—C11—H11B	111.7
O2—C2—C3	121.4 (2)	H11A—C11—H11B	109.5
N2—C2—C3	116.48 (18)	C9—C10'—C11'	107.4 (12)
C8—C3—C4	118.96 (19)	C9—C10'—H10C	110.2
C8—C3—C2	115.13 (18)	C11'—C10'—H10C	110.2
C4—C3—C2	125.89 (18)	C9—C10'—H10D	110.2
C5—C4—C3	118.78 (19)	C11'—C10'—H10D	110.2
C5—C4—N1	118.87 (18)	H10C—C10'—H10D	108.5
C3—C4—N1	122.21 (18)	C10'—C11'—C12	108.3 (12)
C6—C5—C4	121.0 (2)	C10'—C11'—H11C	110.0
C6—C5—H5	119.5	C12—C11'—H11C	110.0
C4—C5—H5	119.5	C10'—C11'—H11D	110.0
C5—C6—C7	120.2 (2)	C12—C11'—H11D	110.0
C5—C6—H6	119.9	H11C—C11'—H11D	108.4
C7—C6—H6	119.9	N2—C12—C1	108.08 (19)
C8—C7—C6	119.1 (2)	N2—C12—C11'	104.2 (8)
C8—C7—H7	120.5	C1—C12—C11'	117.9 (7)
C6—C7—H7	120.5	N2—C12—C11	102.7 (8)
C7—C8—C3	121.9 (2)	C1—C12—C11	106.7 (6)
C7—C8—H8	119.1	N2—C12—H12	112.9
C3—C8—H8	119.1	C1—C12—H12	112.9
N2—C9—C10'	106.4 (8)	C11'—C12—H12	100.6
N2—C9—C10	99.7 (8)	C11—C12—H12	112.9
N2—C9—H9A	111.8	N2—C12—H12'	108.8
C10'—C9—H9A	115.9	C1—C12—H12'	108.8
C10—C9—H9A	111.8	C11'—C12—H12'	108.8
N2—C9—H9B	111.8	C11—C12—H12'	121.1
C10'—C9—H9B	100.8	N1—C13—C14	111.7 (2)
C10—C9—H9B	111.8	N1—C13—H13A	109.3
H9A—C9—H9B	109.6	C14—C13—H13A	109.3
N2—C9—H9C	110.5	N1—C13—H13B	109.3
C10'—C9—H9C	110.5	C14—C13—H13B	109.3
C10—C9—H9C	105.6	H13A—C13—H13B	108.0
H9B—C9—H9C	116.1	C15—C14—C13	124.2 (3)
N2—C9—H9D	110.5	C15—C14—H14	117.9
C10'—C9—H9D	110.5	C13—C14—H14	117.9
C10—C9—H9D	121.5	C14—C15—H15A	120.0
H9A—C9—H9D	101.8	C14—C15—H15B	120.0
H9C—C9—H9D	108.6	H15A—C15—H15B	120.0
C11—C10—C9	104.3 (14)

C4—N1—C1—O1	−180.0 (2)	C2—N2—C9—C10	150.1 (10)
C13—N1—C1—O1	7.7 (3)	C12—N2—C9—C10	−21.4 (10)
C4—N1—C1—C12	−2.2 (3)	N2—C9—C10—C11	41.2 (14)
C13—N1—C1—C12	−174.50 (19)	C10'—C9—C10—C11	−87 (8)
C9—N2—C2—O2	6.1 (3)	C9—C10—C11—C12	−45.3 (16)
C12—N2—C2—O2	176.6 (2)	N2—C9—C10'—C11'	11.4 (17)
C9—N2—C2—C3	−169.74 (19)	C10—C9—C10'—C11'	65 (8)
C12—N2—C2—C3	0.8 (3)	C9—C10'—C11'—C12	−6.8 (19)
O2—C2—C3—C8	−35.3 (3)	C2—N2—C12—C1	70.3 (3)
N2—C2—C3—C8	140.6 (2)	C9—N2—C12—C1	−118.3 (2)
O2—C2—C3—C4	146.2 (2)	C2—N2—C12—C11'	−163.4 (7)
N2—C2—C3—C4	−38.0 (3)	C9—N2—C12—C11'	7.9 (7)
C8—C3—C4—C5	−1.9 (3)	C2—N2—C12—C11	−177.1 (6)
C2—C3—C4—C5	176.60 (19)	C9—N2—C12—C11	−5.7 (6)
C8—C3—C4—N1	173.72 (18)	O1—C1—C12—N2	107.3 (3)
C2—C3—C4—N1	−7.8 (3)	N1—C1—C12—N2	−70.5 (3)
C1—N1—C4—C5	−134.8 (2)	O1—C1—C12—C11'	−10.4 (9)
C13—N1—C4—C5	37.4 (3)	N1—C1—C12—C11'	171.8 (8)
C1—N1—C4—C3	49.6 (3)	O1—C1—C12—C11	−2.6 (8)
C13—N1—C4—C3	−138.2 (2)	N1—C1—C12—C11	179.7 (8)
C3—C4—C5—C6	−0.7 (3)	C10'—C11'—C12—N2	−0.5 (14)
N1—C4—C5—C6	−176.43 (19)	C10'—C11'—C12—C1	119.3 (11)
C4—C5—C6—C7	2.4 (3)	C10'—C11'—C12—C11	85 (7)
C5—C6—C7—C8	−1.4 (4)	C10—C11—C12—N2	30.4 (12)
C6—C7—C8—C3	−1.2 (4)	C10—C11—C12—C1	144.0 (10)
C4—C3—C8—C7	2.9 (3)	C10—C11—C12—C11'	−68 (6)
C2—C3—C8—C7	−175.8 (2)	C1—N1—C13—C14	73.4 (3)
C2—N2—C9—C10'	159.3 (10)	C4—N1—C13—C14	−99.4 (3)
C12—N2—C9—C10'	−12.3 (10)	N1—C13—C14—C15	139.5 (3)

Experimental details

Crystal data
Chemical formula	C₁₅H₁₆N₂O₂
M_r	256.30
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	193
a, b, c (Å)	7.0988 (1), 11.7166 (2), 15.6592 (3)
V (Å³)	1302.44 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.30 × 0.30 × 0.20

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	20329, 2263, 1900
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.714

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.146, 1.04
No. of reflections	2263
No. of parameters	178
No. of restraints	15
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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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