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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 8| August 2012| Page o2449
https://doi.org/10.1107/S1600536812031224

6-Amino­nicotinamide

Lerato P. Ntsalaa and Andreas Lemmerera*

aMolecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Private Bag 3, PO WITS 2050, Johannesburg, South Africa
*Correspondence e-mail: andreas.lemmerer@wits.ac.za

(Received 6 July 2012; accepted 9 July 2012; online 14 July 2012)

In the title compound, C6H7N3O, the amide group is rotated such that the carbonyl O atom is syn to the pyridine N atom, with an O—C—C—C torsion angle of −23.55 (18)°. The crystal packing involves four hydrogen bonds of the types N—H⋯N and N—H⋯O. Two separate centrosymmetric rings are formed using N—H⋯N and N—H⋯O hydrogen bonds that result in a ribbon of 6-aminonicotinamide molecules, joined by the amide and amine functional groups. The remaining two hydrogen bonds are used to generate a three-dimensional packing arrangement.

Related literature

For pharmacological activity, see: Street et al. (1997[Street, C., Alfieri, A. A. & Koutcher, J. A. (1997). Cancer Res. 57, 3956-3962.]); Budihardjo et al. (2000[Budihardjo, I. I., Boerner, S. A., Eckdahl, S., Svingen, P. A., Rios, R., Ames, M. M. & Kaufmann, S. H. (2000). Mol. Pharmacol. 57, 529-538.]). For structurally related compounds, see: Miwa et al. (1999[Miwa, Y., Mizuno, T., Tsuchida, K., Taga, T. & Iwata, Y. (1999). Acta Cryst. B55, 78-84.]); Li et al. (2011[Li, J., Bourne, S. A. & Caira, M. R. (2011). Chem. Commun. 47, 1530-1532.]).

[Scheme 1]

Experimental

Crystal data

  • C6H7N3O

  • Mr = 137.15

  • Monoclinic, P 21 /c

  • a = 14.3483 (6) Å

  • b = 4.8143 (2) Å

  • c = 9.6685 (4) Å

  • β = 99.215 (2)°

  • V = 659.25 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.1 mm−1

  • T = 173 K

  • 0.27 × 0.25 × 0.2 mm
Data collection

  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.974, Tmax = 0.980

  • 4078 measured reflections

  • 1582 independent reflections

  • 1300 reflections with I > 2σ(I)

  • Rint = 0.037
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.113

  • S = 1.03

  • 1582 reflections

  • 107 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.33 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1A⋯O1i 0.888 (18) 2.021 (19) 2.8933 (15) 167.2 (15)
N1—H1S⋯O1ii 0.907 (18) 1.997 (19) 2.9024 (14) 176.0 (16)
N3—H3S⋯N2iii 0.915 (18) 2.125 (19) 3.0322 (15) 170.9 (15)
N3—H3A⋯N3iv 0.875 (17) 2.363 (17) 3.2083 (16) 162.7 (15)
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) -x, -y, -z; (iii) -x+1, -y+1, -z; (iv) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). SAINT-Plus including XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus and XPREP (Bruker 2004[Bruker (2004). SAINT-Plus including XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536812031224/fj2584sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812031224/fj2584Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812031224/fj2584Isup3.mol

Supporting information file. DOI: https://doi.org/10.1107/S1600536812031224/fj2584Isup4.cml

checkCIF report


Comment top

The title compound, 6-aminonicotinamide, and commonly abbreviated to 6AN, is a potent inhibitor of the pentose phosphate pathway (PPP) enzyme, 6PG dehydeogenase, which is an important step in the synthesis of NADPH and ribose units required for biosynthesis and DNA repair (Street et al., 1997). Inhibition of this enzyme by 6-AN leads to accumulation of 6PG. In addition, it has been used in preclinical trials to enhance the effectiveness of cisplatin (Budihardjo et al., 2000). To date, its crystal structure has not been reported.

The asymmetric unit of (I) consists of one molecule of 6AN on a general position and Fig. 1 shows the atomic numbering scheme. There are two single bonds allowing for torsional freedom, the amide group and the amine group, both relative to the pyridine ring. The torsion angle O1—C6—C1—C2 of -23.55 (18) is indicative of a syn conformation of the carbonyl to the pyridine N atom. This conformation is opposite to that of any of the polymorphs of the parent unsubstituted compound, nicotinamide, where the torsion angle ranges from -157.6 (1) to 167.1 (1)° (Miwa et al., 1999; Li et al., 2011). The hydrogen bonding of (I) makes use of all four hydrogen atom donors, two on the amide group and two on the amine. The syn H on the amide forms a homomeric centrosymmetric dimer using N1—H1S···O1 hydrogen bonds, while the H atom syn to the pyridine forms a second centrosymmetric dimer by hydrogen bonding to the pyridine, using N3—H3S···.N2 hydrogen bonds. The combination of these two dimers results in 1-D ribbons extended along the [110] direction. These ribbons are joined by N—-H···O hydrogen bonds from the anti H on the amide group (Fig. 2). Ultimately a 3-D arrangement results (Fig. 3), further supported by the N3—H3A···N3 hydrogen bond from the second H atom on the amine (not shown for clarity in Fig. 3).

Related literature top

For pharmacological activity, see: Street et al. (1997); Budihardjo et al. (2000). For structurally related compounds, see: Miwa et al. (1999); Li et al. (2011).

Experimental top

Crystals of (I) where grown by dissolving 0.200 g (1.46 mmol) in 10 ml of AR-grade methanol and allowing for slow evaporation at room temperature over a few days. Cube-like colourless crystals where obtained.

Refinement top

The C-bound H atoms were geometrically placed (C—H bond lengths of 0.95 for aromatic CH) and refined as riding with Uiso(H) = 1.2Ueq(C). The N-bound H atoms were located in the difference map and coordinates refined freely together with their isotropic thermal parameters.

Structure description top

The title compound, 6-aminonicotinamide, and commonly abbreviated to 6AN, is a potent inhibitor of the pentose phosphate pathway (PPP) enzyme, 6PG dehydeogenase, which is an important step in the synthesis of NADPH and ribose units required for biosynthesis and DNA repair (Street et al., 1997). Inhibition of this enzyme by 6-AN leads to accumulation of 6PG. In addition, it has been used in preclinical trials to enhance the effectiveness of cisplatin (Budihardjo et al., 2000). To date, its crystal structure has not been reported.

The asymmetric unit of (I) consists of one molecule of 6AN on a general position and Fig. 1 shows the atomic numbering scheme. There are two single bonds allowing for torsional freedom, the amide group and the amine group, both relative to the pyridine ring. The torsion angle O1—C6—C1—C2 of -23.55 (18) is indicative of a syn conformation of the carbonyl to the pyridine N atom. This conformation is opposite to that of any of the polymorphs of the parent unsubstituted compound, nicotinamide, where the torsion angle ranges from -157.6 (1) to 167.1 (1)° (Miwa et al., 1999; Li et al., 2011). The hydrogen bonding of (I) makes use of all four hydrogen atom donors, two on the amide group and two on the amine. The syn H on the amide forms a homomeric centrosymmetric dimer using N1—H1S···O1 hydrogen bonds, while the H atom syn to the pyridine forms a second centrosymmetric dimer by hydrogen bonding to the pyridine, using N3—H3S···.N2 hydrogen bonds. The combination of these two dimers results in 1-D ribbons extended along the [110] direction. These ribbons are joined by N—-H···O hydrogen bonds from the anti H on the amide group (Fig. 2). Ultimately a 3-D arrangement results (Fig. 3), further supported by the N3—H3A···N3 hydrogen bond from the second H atom on the amine (not shown for clarity in Fig. 3).

For pharmacological activity, see: Street et al. (1997); Budihardjo et al. (2000). For structurally related compounds, see: Miwa et al. (1999); Li et al. (2011).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I) showing the atomic numbering scheme. Displacement ellipsoids are shown at the 50% probability level.
[Figure 2] Fig. 2. View of the hydrogen-bonded ribbons formed by the centrosymmetric dimers of the amine and amide functional groups of (I). H atoms not involved in hydrogen bonding are omitted for clarity. Intermolecular N—H···N and N—H···O hydrogen bonds are shown as dashed blue lines.
[Figure 3] Fig. 3. Packing diagram of (I). The 3-D network of hydrogen bonds is shown. H atoms not involved in hydrogen bonding are omitted for clarity.
6-Aminonicotinamide top
Crystal data top
C6H7N3OF(000) = 288
Mr = 137.15Dx = 1.382 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1574 reflections
a = 14.3483 (6) Åθ = 2.9–28.4°
b = 4.8143 (2) ŵ = 0.1 mm−1
c = 9.6685 (4) ÅT = 173 K
β = 99.215 (2)°Cube, colourless
V = 659.25 (5) Å30.27 × 0.25 × 0.2 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer		1300 reflections with I > 2σ(I)
ω scansRint = 0.037
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		θmax = 28°, θmin = 2.9°
Tmin = 0.974, Tmax = 0.980h = −18→18
4078 measured reflectionsk = −6→6
1582 independent reflectionsl = −11→12
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.040 w = 1/[σ2(Fo2) + (0.0577P)2 + 0.1618P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.113(Δ/σ)max < 0.001
S = 1.03Δρmax = 0.33 e Å−3
1582 reflectionsΔρmin = −0.21 e Å−3
107 parameters
Crystal data top
C6H7N3OV = 659.25 (5) Å3
Mr = 137.15Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.3483 (6) ŵ = 0.1 mm−1
b = 4.8143 (2) ÅT = 173 K
c = 9.6685 (4) Å0.27 × 0.25 × 0.2 mm
β = 99.215 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer		1582 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1300 reflections with I > 2σ(I)
Tmin = 0.974, Tmax = 0.980Rint = 0.037
4078 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.113H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.33 e Å−3
1582 reflectionsΔρmin = −0.21 e Å−3
107 parameters
Special details top

Experimental. Absorption corrections were made using the program SADABS (Sheldrick, 1996)

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.21465 (8)0.3830 (3)0.06966 (12)0.0216 (3)
C20.28897 (8)0.3112 (3)0.00180 (12)0.0227 (3)
H20.2790.1654−0.06510.027*
C30.38732 (8)0.6424 (2)0.11660 (12)0.0212 (3)
C40.31587 (9)0.7304 (3)0.19125 (13)0.0246 (3)
H40.32710.8780.2570.03*
C50.22979 (9)0.5994 (3)0.16746 (13)0.0242 (3)
H50.18080.65520.2170.029*
C60.12477 (8)0.2249 (3)0.03728 (12)0.0235 (3)
N10.06896 (8)0.2202 (3)0.13454 (12)0.0315 (3)
H1S0.0150 (13)0.121 (3)0.1119 (18)0.037 (4)*
H1A0.0869 (12)0.292 (3)0.219 (2)0.036 (4)*
N20.37410 (7)0.4326 (2)0.02370 (11)0.0232 (3)
N30.47474 (8)0.7598 (2)0.14074 (13)0.0275 (3)
H3S0.5162 (12)0.710 (4)0.0824 (19)0.037 (4)*
H3A0.4816 (12)0.918 (3)0.1855 (18)0.034 (4)*
O10.10436 (6)0.0996 (2)−0.07631 (9)0.0295 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0207 (5)0.0269 (6)0.0175 (5)−0.0015 (4)0.0042 (4)0.0035 (4)
C20.0232 (6)0.0257 (6)0.0194 (6)−0.0029 (5)0.0045 (4)−0.0017 (5)
C30.0206 (6)0.0219 (6)0.0208 (6)−0.0007 (4)0.0027 (4)0.0028 (4)
C40.0275 (6)0.0239 (6)0.0229 (6)−0.0008 (5)0.0058 (5)−0.0034 (5)
C50.0234 (6)0.0281 (6)0.0223 (6)0.0026 (5)0.0078 (5)0.0010 (5)
C60.0203 (6)0.0320 (6)0.0185 (6)−0.0012 (5)0.0039 (4)0.0023 (5)
N10.0246 (6)0.0497 (7)0.0219 (6)−0.0122 (5)0.0086 (4)−0.0067 (5)
N20.0219 (5)0.0260 (5)0.0224 (5)−0.0017 (4)0.0061 (4)−0.0017 (4)
N30.0229 (6)0.0275 (6)0.0329 (6)−0.0045 (4)0.0068 (4)−0.0066 (5)
O10.0250 (5)0.0451 (6)0.0190 (5)−0.0094 (4)0.0057 (3)−0.0040 (4)
Geometric parameters (Å, º) top
C1—C21.3824 (17)C4—H40.95
C1—C51.4004 (17)C5—H50.95
C1—C61.4870 (16)C6—O11.2461 (15)
C2—N21.3401 (15)C6—N11.3293 (16)
C2—H20.95N1—H1S0.907 (18)
C3—N21.3449 (15)N1—H1A0.888 (18)
C3—N31.3614 (15)N3—H3S0.915 (18)
C3—C41.4100 (17)N3—H3A0.875 (17)
C4—C51.3730 (17)
C2—C1—C5117.29 (11)C4—C5—H5120.2
C2—C1—C6118.75 (11)C1—C5—H5120.2
C5—C1—C6123.95 (11)O1—C6—N1122.15 (12)
N2—C2—C1124.66 (11)O1—C6—C1120.45 (11)
N2—C2—H2117.7N1—C6—C1117.39 (11)
C1—C2—H2117.7C6—N1—H1S115.2 (11)
N2—C3—N3116.99 (11)C6—N1—H1A121.9 (11)
N2—C3—C4122.08 (11)H1S—N1—H1A122.5 (16)
N3—C3—C4120.87 (11)C2—N2—C3117.43 (10)
C5—C4—C3118.99 (11)C3—N3—H3S117.2 (11)
C5—C4—H4120.5C3—N3—H3A118.4 (11)
C3—C4—H4120.5H3S—N3—H3A120.1 (15)
C4—C5—C1119.53 (11)
C5—C1—C2—N20.43 (19)C2—C1—C6—O1−23.55 (18)
C6—C1—C2—N2−178.45 (11)C5—C1—C6—O1157.66 (12)
N2—C3—C4—C5−0.61 (19)C2—C1—C6—N1155.44 (12)
N3—C3—C4—C5−177.58 (11)C5—C1—C6—N1−23.36 (18)
C3—C4—C5—C1−0.24 (18)C1—C2—N2—C3−1.24 (18)
C2—C1—C5—C40.34 (18)N3—C3—N2—C2178.40 (11)
C6—C1—C5—C4179.15 (11)C4—C3—N2—C21.31 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O1i0.888 (18)2.021 (19)2.8933 (15)167.2 (15)
N1—H1S···O1ii0.907 (18)1.997 (19)2.9024 (14)176.0 (16)
N3—H3S···N2iii0.915 (18)2.125 (19)3.0322 (15)170.9 (15)
N3—H3A···N3iv0.875 (17)2.363 (17)3.2083 (16)162.7 (15)
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) −x, −y, −z; (iii) −x+1, −y+1, −z; (iv) −x+1, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC6H7N3O
Mr137.15
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)14.3483 (6), 4.8143 (2), 9.6685 (4)
β (°) 99.215 (2)
V (Å3)659.25 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.1
Crystal size (mm)0.27 × 0.25 × 0.2
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.974, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections		4078, 1582, 1300
Rint0.037
(sin θ/λ)max (Å−1)0.661
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.113, 1.03
No. of reflections1582
No. of parameters107
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.33, −0.21

Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O1i0.888 (18)2.021 (19)2.8933 (15)167.2 (15)
N1—H1S···O1ii0.907 (18)1.997 (19)2.9024 (14)176.0 (16)
N3—H3S···N2iii0.915 (18)2.125 (19)3.0322 (15)170.9 (15)
N3—H3A···N3iv0.875 (17)2.363 (17)3.2083 (16)162.7 (15)
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) −x, −y, −z; (iii) −x+1, −y+1, −z; (iv) −x+1, y+1/2, −z+1/2.
 

Acknowledgements

This work was supported by the University of the Witwatersrand and the Mol­ecular Sciences Institute, which are thanked for providing the infrastructure required to carry out this work. The Friedel Sellshop Grant is thanked for additional financial support.

References

First citationBruker (2004). SAINT-Plus including XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationBruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationBudihardjo, I. I., Boerner, S. A., Eckdahl, S., Svingen, P. A., Rios, R., Ames, M. M. & Kaufmann, S. H. (2000). Mol. Pharmacol. 57, 529–538.  Web of Science PubMed CAS Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
 First citationLi, J., Bourne, S. A. & Caira, M. R. (2011). Chem. Commun. 47, 1530–1532.  Web of Science CSD CrossRef CAS Google Scholar
 First citationMacrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationMiwa, Y., Mizuno, T., Tsuchida, K., Taga, T. & Iwata, Y. (1999). Acta Cryst. B55, 78–84.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationStreet, C., Alfieri, A. A. & Koutcher, J. A. (1997). Cancer Res. 57, 3956–3962.  CAS PubMed Web of Science Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 8| August 2012| Page o2449
https://doi.org/10.1107/S1600536812031224
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