Powder study of hydro­chloro­thia­zide form II

Florence, A.; Johnston, A.; Fernandes, P.; Shankland, K.; Stevens, H.N.E.; Osmundsen, S.; Mullen, A.B.

doi:10.1107/S1600536805023640

organic compounds

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ISSN: 2056-9890

Volume 61| Part 9| September 2005| Pages o2798-o2800

https://doi.org/10.1107/S1600536805023640

Powder study of hydrochlorothiazide form II

Alastair Florence,^a ^* Andrea Johnston,^a Philippe Fernandes,^a Kenneth Shankland,^b Howard N. E. Stevens,^a Sigrunn Osmundsen ^a and Alexander B. Mullen ^a

^aDepartment of Pharmaceutical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, Scotland, and ^bISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX, England
^*Correspondence e-mail: alastair.florence@strath.ac.uk

(Received 14 July 2005; accepted 25 July 2005; online 6 August 2005)

The crystal structure of hydrochlorothiazide form II, C₇H₈ClN₃O₄S₂, was solved by simulated annealing from laboratory X-ray powder diffraction data collected at room temperature to 1.76 Å resolution. Subsequent Rietveld refinement yielded an R_wp of 0.0376 to 1.49 Å resolution. The molecules crystallize in the space group P2₁/c with one molecule in the asymmetric unit. The structure is stabilized by three N—H⋯N and one N—H⋯O hydrogen-bonded intermolecular interaction.

Comment

Hydrochlorothiazide (HCT) is a thiazide diuretic which is known to crystallize in at least one non-solvated form (Dupont & Dideberg, 1972 ). A polycrystalline sample of a second polymorph of HCT, form II, (I), was produced using a modified precipitation technique in which an acetone solution of HCT was added to distilled water containing hydroxypropylmethylcellulose (grade E5LV, Dow Chemicals, USA) under

agitation. The resulting precipitate was immediately isolated from solution by membrane filtration. The sample was identified as a new form using multisample X-ray powder diffraction analysis (Florence et al., 2003

). The sample was found to contain a trace amount of HCT form I (Dupont & Dideberg, 1972

The crystal structure of (I) was solved by simulated annealing using laboratory X-ray powder diffraction data (Fig. 1). The compound crystallizes in space group P2₁/c with one molecule in the asymmetric unit (Fig. 2). In (I), the N2/S1/C1/C2/N1/C3 ring in HCT displays a non-planar conformation, atoms N2 and C3 having the largest deviations [0.458 (1) and −0.266 (1) Å, respectively] from the least-squares plane through the aromatic ring. The sulfonamide side chain adopts a torsion angle N3—S2—C5—C6 = 59.53 (19)°, such that O1 eclipses H4, and atoms O4 and N3 are staggered with respect to Cl1. In HCT form I (Dupont & Dideberg, 1972), this group is rotated by approximately 120° compared with (I), such that the amine group lies on the opposite side of the benzothiadiazine ring system.

The crystal structure is stabilized by a series of intermolecular contacts including three N—H⋯N hydrogen bonds (contacts 1–3, Fig. 3), one N—H⋯O hydrogen bond (contact 4) and a C—H⋯O contact (contact 5). Contact 1 forms a centrosymmetric R₂²(8) dimer motif (Fig. 4, A), whilst contacts 3 and 4 produce a larger R₄⁴(24) motif (Fig. 4, B) connecting four molecules of HCT. Contacts 2 and 3 also combine to produce an R₄²(20) ring motif (Fig. 4, C).

Figure 1
Final observed (points), calculated (line) and difference [(y_obs − y_calc)/σ(y_obs)] profiles for the Rietveld refinement of the title compound.

Figure 2
The molecular structure with the atom-numbering scheme. Isotropic displacement spheres are shown at the 50% probability level.

Figure 3
Packing diagram illustrating intermolecular contacts (dashed lines) in the structure of (I)

. Unique contacts are labelled as follows: 1: N2⋯O3 = 2.905 (4) Å, O3 in the molecule at (−x, 1 − y, −z); 2: N1⋯O1 = 2.920 (3) Å, O1 in the molecule at (x,1/2 − y,- $[{1\over 2}]$ + z); 3: N3⋯O1 = 3.121 (3) Å, O1 in the molecule at (1 − x, $[{1\over 2}]$ + y, $[{1\over 2}]$ − z); 4: N3⋯N2 = 3.214 (2) Å, N2 in the molecule at (1 + x, $[{1\over 2}]$ − y, $[{1\over 2}]$ + z); 5: C3⋯O2 = 3.416 (3) Å, O2 in the molecule at (−x, $[{1\over 2}]$ + y, − $[{1\over 2}]$ − z). Contacts calculated and illustrated using PLATON (Spek, 2003

; program version 280604).

Figure 4
(Top) The R₂²(8) (labelled A) and R₄⁴(24) (labelled B) motifs within the structure of (I)

. (Bottom left) The R₄²(20) motif, shown with atoms not involved in the motif omitted for clarity.

Experimental

A sample of (I), obtained using the method described in the Comment, was lightly ground in a mortar, loaded into a 0.7 mm borosilicate glass capillary and mounted on the diffractometer. Data were collected from a sample in a rotating 0.7 mm borosilicate glass capillary using a variable count time scheme (Shankland et al., 1997 ; Hill & Madsen, 2002 $[Hill, R. J. & Madsen, I. C. (2002). Structure Determination from Powder Diffraction Data, edited by W. I. F. David, K. Shankland, L. B. McCusker & Ch. Baerlocher, pp.114-116. Oxford University Press.]$ ).

Crystal data

C₇H₈ClN₃O₄S₂
M_r = 297.75
Monoclinic, P 2₁ /c
a = 9.4884 (5) Å
b = 8.3334 (4) Å
c = 15.1309 (7) Å
β = 113.2087 (19)°
V = 1099.59 (9) Å³
Z = 4
D_x = 1.799 Mg m⁻³
Cu Kα₁ radiation
μ = 6.75 mm⁻¹
T = 298 K
Specimen shape: cylinder
12 × 0.7 mm
Specimen prepared at 298 K
Particle morphology: visual estimate, prisms, white

Data collection

Bruker AXS D8 Advance diffractometer
Specimen mounting: 0.7 mm borosilicate capillary
Specimen mounted in transmission mode
Scan method: step
Absorption correction: none
2θ_min = 5.0, 2θ_max = 65.0°
Increment in 2θ = 0.017°

Refinement

Refinement on I_net
R_p = 0.033
R_wp = 0.038
R_exp = 0.023
R_B = 0.013
S = 1.64
Excluded region(s): 62.1 to 65.0% due to poor signal-to-noise
Profile function: fundamental parameters with axial divergence correction
355 reflections
92 parameters
Only H-atom coordinates refined
Weighting scheme based on measured s.u.'s 1/σ(Y_obs)²
(Δ/σ)_max = 0.005
Preferred orientation correction: a spherical harmonics-based preferred orientation correction was applied with TOPAS during the Rietveld refinement

Table 1
Selected geometric parameters (Å, °)

Cl1—C6	1.730 (2)
S1—O2	1.425 (3)
S1—O3	1.426 (2)
S1—N2	1.6438 (16)
S1—C1	1.7650 (17)
S2—O1	1.428 (2)
S2—O4	1.429 (3)
S2—N3	1.633 (2)
S2—C5	1.772 (2)
N1—C2	1.358 (2)
N1—C3	1.473 (2)
N2—C3	1.441 (2)

O2—S1—O3	119.4 (2)
O2—S1—N2	110.42 (13)
O2—S1—C1	108.92 (17)
O3—S1—N2	106.39 (18)
O3—S1—C1	109.25 (10)
N2—S1—C1	100.90 (10)
O1—S2—O4	122.35 (19)
O1—S2—N3	106.27 (14)
O1—S2—C5	105.68 (13)
O4—S2—N3	107.67 (14)
O4—S2—C5	108.82 (13)
N3—S2—C5	104.75 (10)
C2—N1—C3	123.27 (16)
S1—N2—C3	113.58 (11)
S1—C1—C2	119.80 (11)
S1—C1—C4	119.55 (11)
N1—C2—C1	121.84 (13)
N1—C2—C7	120.34 (13)
N1—C3—N2	108.10 (11)
S2—C5—C4	117.40 (12)
S2—C5—C6	124.83 (13)
Cl1—C6—C5	121.28 (16)
Cl1—C6—C7	117.16 (14)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H5⋯O3ⁱ	0.95 (1)	2.03 (1)	2.905 (4)	152 (1)
N1—H6⋯O1ⁱⁱ	0.94 (1)	2.02 (1)	2.920 (3)	159 (1)
N3—H7⋯O1ⁱⁱⁱ	0.95 (1)	2.21 (1)	3.121 (3)	161 (1)
N3—H8⋯N2^iv	0.95 (1)	2.37 (1)	3.214 (2)	149 (1)
C3—H1⋯O2^v	0.95 (1)	2.56 (1)	3.416 (3)	150 (1)
C4—H4⋯O1	0.95 (1)	2.37 (1)	2.803 (3)	108 (1)
Symmetry codes: (i) -x, -y+1, -z; (ii) $[x, -y+{\script{1\over 2}}, +z-{\script{1\over 2}}]$ ; (iii) $[-x+1, +y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iv) $[x+1, -y+{\script{1\over 2}}, +z+{\script{1\over 2}}]$ ; (v) $[-x, +y+{\script{1\over 2}}, -z-{\script{1\over 2}}]$ .

The diffraction pattern indexed to a monoclinic cell [M(20) = 25.9, F(20) = 70.7; DICVOL-91; Boultif & Louer, 1991 ), and space group P2₁/c was assigned from volume considerations and a statistical consideration of the systematic absences (Markvardsen et al., 2001 ). The data set was background subtracted and truncated to 52.2° 2θ for Pawley (1981 ) fitting (χ²_Pawley = 5.17) and the structure was solved using the simulated annealing (SA) global optimization procedure (David et al., 1998 ), which is now implemented in the DASH computer program (David et al., 1998 ). The SA structure solution involved the optimization of one molecule of HCT, totaling 7 degrees of freedom. The best SA solution had a favourable χ²_SA/χ²_Pawley ratio of 2.6, a chemically reasonable packing arrangement and exhibited no significant misfit to the data. Prior to Rietveld refinement, atoms H7 and H8 were set to positions which satisfied the hydrogen bonding contacts within the structure. The solved structure was subsequently refined with data in the range 6.0–62.1° 2θ using a restrained Rietveld (1969 ) method, as implemented in TOPAS (Coelho, 2003 ), with the R_wp falling to 0.038 during the refinement. A joint refinement strategy was implemented, in which the structure of HCT form I (Dupont & Dideberg, 1972) was included to take account of the impurity peaks arising from the presence of a small amount (estimated at less than 5%) of this polymorph in the sample. In the course of the refinement, the form I unit-cell and peak-shape parameters were allowed to vary, whilst all atomic coordinates were fixed. All atomic positions (including H atoms) for the form II structure were refined, subject to a series of restraints on bond lengths, bond angles and planarity. U_iso(H) values were set at 0.044 Å². A spherical harmonics correction of intensities for preferred orientation was applied in the final refinement. The observed and calculated diffraction patterns for the refined crystal structure are shown in Fig. 1.

Data collection: DIFFRAC plus XRD Commander (Kienle & Jacob, 2003 ); cell refinement: TOPAS (Coelho, 2003); data reduction: DASH (David et al., 2001); program(s) used to solve structure: DASH; program(s) used to refine structure: TOPAS; molecular graphics: PLATON (Spek, 2003 ); software used to prepare material for publication: enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks hydrochlorothiazide-formII, I. DOI: https://doi.org/10.1107/S1600536805023640/hg6211sup1.cif

Rietveld powder data: contains datablock I. DOI: https://doi.org/10.1107/S1600536805023640/hg6211Isup2.rtv

Computing details top

Data collection: DIFFRAC plus XRD Commander (Kienle & Jacob, 2003); data reduction: DASH (David et al., 2001); program(s) used to solve structure: DASH; program(s) used to refine structure: TOPAS (Coelho, 2003); software used to prepare material for publication: enCIFer (Allen et al., 2004).

(I) top

Crystal data top

C₇H₈ClN₃O₄S₂	F(000) = 608.0
M_r = 297.75	D_x = 1.799 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα₁ radiation, λ = 1.54056 Å
Hall symbol: -P 2ybc	µ = 6.75 mm⁻¹
a = 9.4884 (5) Å	T = 298 K
b = 8.3334 (4) Å	Particle morphology: visual estimate, prisms
c = 15.1309 (7) Å	white
β = 113.2087 (19)°	cylinder, 12 × 0.7 mm
V = 1099.59 (9) Å³	Specimen preparation: Prepared at 298 K
Z = 4

Data collection top

Bruker AXS D8 Advance diffractometer	Data collection mode: transmission
Radiation source: sealed X-ray tube, Bruker-AXS D8	Scan method: step
Primary focussing, Ge 111 monochromator	2θ_min = 5.0°, 2θ_max = 65.0°, 2θ_step = 0.017°
Specimen mounting: 0.7 mm borosilicate capillary

Refinement top

Least-squares matrix: selected elements only	92 parameters
R_p = 0.033	47 restraints
R_wp = 0.038	1 constraint
R_exp = 0.023	Only H-atom coordinates refined
R_Bragg = 0.013	Weighting scheme based on measured s.u.'s 1/σ(Y_obs)²
3529 data points	(Δ/σ)_max = 0.005
Excluded region(s): 62.1 to 65.0 due to poor signal to noise	Background function: Chebyshev polynomial
Profile function: Fundamental parameters with axial divergence correction	Preferred orientation correction: A spherical harmonics-based preferred orientation correction was applied with Topas during the Rietveld refinement.

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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

	x	y	z	U_iso*/U_eq
Cl1	0.75173 (15)	0.1570 (3)	0.12511 (14)	0.0269 (4)*
S1	0.04110 (12)	0.25043 (13)	−0.05257 (7)	0.0269 (4)*
S2	0.53828 (12)	−0.00769 (14)	0.22842 (7)	0.0269 (4)*
O1	0.41184 (17)	−0.0340 (4)	0.25537 (14)	0.0269 (4)*
O2	−0.0243 (4)	0.1139 (3)	−0.1111 (2)	0.0269 (4)*
O3	−0.0117 (2)	0.2956 (5)	0.02000 (11)	0.0269 (4)*
O4	0.6253 (3)	−0.1367 (3)	0.21308 (19)	0.0269 (4)*
N1	0.26907 (15)	0.3922 (3)	−0.12379 (11)	0.0269 (4)*
N2	0.02352 (17)	0.41019 (14)	−0.11982 (8)	0.0269 (4)*
N3	0.65720 (17)	0.10948 (14)	0.31064 (14)	0.0269 (4)*
C1	0.24235 (12)	0.2284 (2)	−0.00040 (9)	0.0269 (4)*
C2	0.33184 (13)	0.3004 (2)	−0.04357 (9)	0.0269 (4)*
C3	0.10325 (14)	0.39732 (15)	−0.18320 (9)	0.0269 (4)*
C4	0.30954 (13)	0.1390 (2)	0.08259 (9)	0.0269 (4)*
C5	0.46572 (15)	0.1121 (2)	0.12321 (12)	0.0269 (4)*
C6	0.55492 (15)	0.1828 (3)	0.07942 (12)	0.0269 (4)*
C7	0.49079 (13)	0.2748 (2)	−0.00157 (9)	0.0269 (4)*
H1	0.0814 (8)	0.4892 (11)	−0.2234 (7)	0.044*
H2	0.0707 (10)	0.3011 (11)	−0.2187 (6)	0.044*
H3	0.5541 (9)	0.3160 (10)	−0.0320 (6)	0.044*
H4	0.2476 (9)	0.0937 (11)	0.1121 (6)	0.044*
H5	0.0555 (9)	0.5041 (11)	−0.0813 (6)	0.044*
H6	0.3375 (9)	0.4321 (11)	−0.1498 (6)	0.044*
H7	0.6580 (8)	0.2158 (10)	0.2881 (6)	0.044*
H8	0.7567 (9)	0.0647 (11)	0.3389 (6)	0.044*

Geometric parameters (Å, º) top

Cl1—C6	1.730 (2)	N2—H5	0.951 (9)
S1—O2	1.425 (3)	N3—H7	0.951 (8)
S1—O3	1.426 (2)	N3—H8	0.946 (9)
S1—N2	1.6438 (16)	C1—C2	1.3946 (19)
S1—C1	1.7650 (17)	C1—C4	1.381 (2)
S2—O1	1.428 (2)	C2—C7	1.4031 (19)
S2—O4	1.429 (3)	C4—C5	1.381 (2)
S2—N3	1.633 (2)	C5—C6	1.394 (2)
S2—C5	1.772 (2)	C6—C7	1.368 (2)
N1—C2	1.358 (2)	C3—H1	0.949 (9)
N1—C3	1.473 (2)	C3—H2	0.947 (9)
N2—C3	1.441 (2)	C4—H4	0.946 (9)
N1—H6	0.943 (9)	C7—H3	0.953 (9)

O2—S1—O3	119.4 (2)	S1—C1—C4	119.55 (11)
O2—S1—N2	110.42 (13)	C1—C2—C7	117.82 (13)
O2—S1—C1	108.92 (17)	N1—C2—C1	121.84 (13)
O3—S1—N2	106.39 (18)	N1—C2—C7	120.34 (13)
O3—S1—C1	109.25 (10)	N1—C3—N2	108.10 (11)
N2—S1—C1	100.90 (10)	C1—C4—C5	121.48 (13)
O1—S2—O4	122.35 (19)	S2—C5—C4	117.40 (12)
O1—S2—N3	106.27 (14)	S2—C5—C6	124.83 (13)
O1—S2—C5	105.68 (13)	C4—C5—C6	117.77 (15)
O4—S2—N3	107.67 (14)	Cl1—C6—C5	121.28 (16)
O4—S2—C5	108.82 (13)	Cl1—C6—C7	117.16 (14)
N3—S2—C5	104.75 (10)	C5—C6—C7	121.56 (15)
C2—N1—C3	123.27 (16)	C2—C7—C6	120.67 (13)
S1—N2—C3	113.58 (11)	N1—C3—H1	109.0 (6)
C2—N1—H6	116.1 (6)	N1—C3—H2	110.7 (6)
C3—N1—H6	118.7 (5)	N2—C3—H1	109.1 (6)
S1—N2—H5	110.9 (5)	N2—C3—H2	107.5 (6)
C3—N2—H5	110.2 (6)	H1—C3—H2	112.3 (8)
S2—N3—H7	112.6 (5)	C1—C4—H4	119.6 (5)
S2—N3—H8	112.0 (6)	C5—C4—H4	118.9 (6)
H7—N3—H8	112.5 (8)	C2—C7—H3	119.7 (5)
C2—C1—C4	120.66 (12)	C6—C7—H3	119.5 (5)
S1—C1—C2	119.80 (11)

O2—S1—N2—C3	−62.4 (2)	S1—N2—C3—N1	−66.39 (16)
O3—S1—N2—C3	166.72 (13)	C2—C1—C4—C5	−2.8 (2)
C1—S1—N2—C3	52.73 (12)	S1—C1—C2—C7	−177.71 (12)
O2—S1—C1—C2	96.13 (19)	C4—C1—C2—N1	−178.32 (17)
O2—S1—C1—C4	−83.47 (19)	S1—C1—C2—N1	2.1 (2)
O3—S1—C1—C2	−131.9 (2)	S1—C1—C4—C5	176.79 (13)
O3—S1—C1—C4	48.5 (2)	C4—C1—C2—C7	1.9 (2)
N2—S1—C1—C2	−20.07 (15)	N1—C2—C7—C6	179.82 (19)
N2—S1—C1—C4	160.33 (13)	C1—C2—C7—C6	−0.4 (2)
O1—S2—C5—C4	−7.5 (2)	C1—C4—C5—S2	−178.81 (13)
O1—S2—C5—C6	171.5 (2)	C1—C4—C5—C6	2.1 (3)
O4—S2—C5—C4	125.57 (18)	S2—C5—C6—C7	−179.59 (15)
O4—S2—C5—C6	−55.4 (2)	S2—C5—C6—Cl1	0.7 (3)
N3—S2—C5—C4	−119.51 (15)	C4—C5—C6—Cl1	179.73 (17)
N3—S2—C5—C6	59.5 (2)	C4—C5—C6—C7	−0.6 (3)
C3—N1—C2—C7	166.79 (16)	C5—C6—C7—C2	−0.3 (3)
C3—N1—C2—C1	−13.0 (3)	Cl1—C6—C7—C2	179.46 (16)
C2—N1—C3—N2	44.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H5···O3ⁱ	0.95 (1)	2.03 (1)	2.905 (4)	152 (1)
N1—H6···O1ⁱⁱ	0.94 (1)	2.02 (1)	2.920 (3)	159 (1)
N3—H7···O1ⁱⁱⁱ	0.95 (1)	2.21 (1)	3.121 (3)	161 (1)
N3—H8···N2^iv	0.95 (1)	2.37 (1)	3.214 (2)	149 (1)
C3—H1···O2^v	0.95 (1)	2.56 (1)	3.416 (3)	150 (1)
C4—H4···O1	0.95 (1)	2.37 (1)	2.803 (3)	108 (1)

Symmetry codes: (i) −x, −y+1, −z; (ii) x, −y+1/2, z−1/2; (iii) −x+1, y+1/2, −z+1/2; (iv) x+1, −y+1/2, z+1/2; (v) −x, y+1/2, −z−1/2.

Acknowledgements

We thank the Basic Technology programme of the UK Research Councils for funding under the project Control and Prediction of the Organic Solid State (https://www.cposs.org.uk). We also thank the CCLRC Centre for Molecular Structure and Dynamics and Pharmaceutics International Inc. (Baltimore, USA) for studentship funding for PF and SO, respectively, and the EPSRC for grant GR/N07462/01.

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