DL-2-Amino-2-thia­zoline-4-carboxyl­ic acid trihydrate

In the title compound, C₄H₆N₂O₂S.·3H₂O, the 2-amino-2-thia­zoline-4-carboxyl­ic acid mol­ecule is in a zwitterionic form and shows amino–imino tautomerism. There are intermolecular O—H...O, O—H...N, N—H...O and C—H...O interactions, forming a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.023
• wR factor = 0.082
• Data-to-parameter ratio = 13.5

checkCIF/PLATON results

No syntax errors found



Alert level C
STRVA01_ALERT_4_C           Flack test results are ambiguous.
           From the CIF: _refine_ls_abs_structure_Flack    0.490
           From the CIF: _refine_ls_abs_structure_Flack_su    0.090
PLAT033_ALERT_2_C Flack Parameter Value Deviates from Zero .......       0.49
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT128_ALERT_4_C Non-standard setting of Space group Pca21   ....    P21ab
PLAT250_ALERT_2_C Large U3/U1 ratio for average U(i,j) tensor ....       2.10
PLAT731_ALERT_1_C Bond    Calc     0.83(4), Rep   0.825(19) ......       2.11 su-Rat
              O5   -H5A     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.86(4), Rep   0.854(19) ......       2.11 su-Rat
              O5   -H5B     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.83(4), Rep   0.825(19) ......       2.11 su-Rat
              O5   -H5A     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.86(4), Rep   0.854(19) ......       2.11 su-Rat
              O5   -H5B     1.555   1.555
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          2
              H2 O
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          3
              H2 O

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.42
           From the CIF: _reflns_number_total               1968
           Count of symmetry unique reflns         1116
           Completeness (_total/calc)            176.34%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       852
           Fraction of Friedel pairs measured     0.763
           Are heavy atom types Z>Si present          yes

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
  11 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   5 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   5 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC & Rigaku, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

(I)

Crystal data

C4H6N2O2S·3H2O	F(000) = 424
Mr = 200.22	Dx = 1.466 Mg m^−3
Orthorhombic, P21ab	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P -2b 2a	Cell parameters from 11305 reflections
a = 8.0835 (4) Å	θ = 2.5–27.4°
b = 8.1546 (3) Å	µ = 0.35 mm^−1
c = 13.7591 (7) Å	T = 293 K
V = 906.97 (7) Å^3	Prism, colorless
Z = 4	0.3 × 0.29 × 0.25 mm

Data collection

Rigaku R-AXIS RAPID diffractometer	1620 reflections with I > 2σ(I)
Detector resolution: 10.00 pixels mm^-1	Rint = 0.019
ω scans	θmax = 27.4°, θmin = 1.5°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −10→10
Tmin = 0.849, Tmax = 0.917	k = −10→10
8161 measured reflections	l = −17→17
1968 independent reflections

Refinement

Refinement on F^2	w = 1/[σ^2(Fo^2) + (0.0444P)^2] where P = (Fo^2 + 2Fc^2)/3
Least-squares matrix: full	(Δ/σ)max = 0.004
R[F^2 > 2σ(F^2)] = 0.023	Δρmax = 0.23 e Å^−3
wR(F^2) = 0.082	Δρmin = −0.15 e Å^−3
S = 1.07	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1968 reflections	Extinction coefficient: 0.010 (2)
146 parameters	Absolute structure: Flack (1983), 852 Friedel pairs
10 restraints	Absolute structure parameter: 0.49 (9)
H atoms treated by a mixture of independent and constrained refinement

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
S	0.34336 (8)	0.21566 (6)	0.19887 (4)	0.03618 (16)
O1	0.3635 (3)	−0.21679 (19)	0.40829 (12)	0.0473 (5)
O2	0.4055 (2)	−0.3504 (2)	0.27003 (13)	0.0470 (5)
O3	0.1931 (2)	−0.4669 (2)	0.49423 (13)	0.0380 (4)
O4	0.4469 (3)	−0.3793 (3)	0.07247 (15)	0.0505 (5)
O5	0.1440 (3)	0.1299 (3)	0.0036 (2)	0.0716 (7)
N1	0.4909 (3)	0.0671 (2)	0.33846 (14)	0.0306 (4)
N2	0.4767 (3)	0.3507 (2)	0.35625 (15)	0.0389 (5)
C1	0.3293 (4)	−0.0063 (2)	0.20038 (17)	0.0392 (6)
C2	0.4635 (3)	−0.0667 (2)	0.27056 (15)	0.0296 (4)
C3	0.4474 (3)	0.2142 (3)	0.30938 (15)	0.0289 (4)
C4	0.4062 (3)	−0.2241 (3)	0.32158 (17)	0.0315 (5)
H1	0.558 (3)	0.042 (4)	0.3836 (17)	0.043 (8)*
H1A	0.2208	−0.0408	0.2225	0.047*
H1B	0.3478	−0.0503	0.1358	0.047*
H2	0.5656	−0.0886	0.2344	0.036*
H2A	0.443 (4)	0.439 (3)	0.327 (2)	0.055 (9)*
H2B	0.540 (3)	0.350 (4)	0.4061 (16)	0.044 (8)*
H3A	0.259 (4)	−0.532 (4)	0.522 (2)	0.064 (10)*
H3B	0.255 (4)	−0.400 (3)	0.468 (2)	0.055 (10)*
H4A	0.348 (3)	−0.388 (4)	0.051 (2)	0.067 (10)*
H4B	0.430 (5)	−0.378 (4)	0.1326 (14)	0.073 (12)*
H5A	0.082 (5)	0.055 (4)	0.021 (3)	0.087 (15)*
H5B	0.077 (5)	0.202 (4)	−0.019 (3)	0.090 (15)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S	0.0455 (3)	0.0275 (2)	0.0356 (3)	0.0026 (3)	−0.0055 (3)	0.0069 (2)
O1	0.0738 (14)	0.0288 (7)	0.0391 (8)	−0.0096 (10)	0.0119 (10)	0.0007 (7)
O2	0.0803 (15)	0.0219 (7)	0.0387 (9)	−0.0001 (8)	−0.0030 (9)	−0.0025 (7)
O3	0.0413 (10)	0.0346 (9)	0.0380 (9)	−0.0022 (8)	−0.0034 (8)	0.0038 (8)
O4	0.0499 (13)	0.0585 (12)	0.0432 (11)	0.0009 (11)	0.0019 (10)	−0.0039 (9)
O5	0.0502 (13)	0.0704 (17)	0.0941 (19)	0.0039 (13)	0.0108 (12)	0.0261 (15)
N1	0.0382 (11)	0.0220 (8)	0.0317 (9)	−0.0008 (9)	−0.0060 (9)	0.0030 (7)
N2	0.0545 (14)	0.0239 (9)	0.0383 (12)	0.0005 (10)	−0.0063 (10)	0.0022 (9)
C1	0.0561 (16)	0.0252 (9)	0.0362 (11)	0.0003 (14)	−0.0084 (13)	0.0016 (9)
C2	0.0364 (11)	0.0217 (9)	0.0307 (10)	0.0009 (9)	0.0025 (10)	−0.0010 (8)
C3	0.0309 (11)	0.0255 (10)	0.0303 (11)	0.0000 (9)	0.0034 (9)	0.0017 (9)
C4	0.0379 (12)	0.0225 (9)	0.0341 (12)	0.0012 (9)	−0.0026 (9)	0.0024 (9)

Geometric parameters (Å, º)

S—C3	1.738 (2)	N1—H1	0.848 (17)
S—C1	1.814 (2)	N2—H2A	0.867 (18)
O1—C4	1.243 (3)	N2—H2B	0.856 (17)
O3—H3A	0.846 (18)	C1—C2	1.533 (4)
O3—H3B	0.821 (18)	C1—H1A	0.97
O4—H4A	0.855 (19)	C1—H1B	0.97
O4—H4B	0.839 (18)	C2—H2	0.98
O5—H5A	0.825 (19)	C3—N2	1.308 (3)
O5—H5B	0.854 (19)	C4—O2	1.250 (3)
N1—C3	1.313 (3)	C4—C2	1.534 (3)
N1—C2	1.454 (3)
S—C1—H1A	110.4	C2—C1—S	106.47 (17)
S—C1—H1B	110.4	C2—C1—H1A	110.4
O1—C4—O2	125.6 (2)	C2—C1—H1B	110.4
O1—C4—C2	118.88 (19)	C3—S—C1	90.77 (11)
O2—C4—C2	115.5 (2)	C3—N1—C2	116.70 (19)
N1—C2—C1	105.76 (17)	C3—N1—H1	128 (2)
N1—C2—C4	112.33 (18)	C3—N2—H2A	115 (2)
N1—C3—S	113.74 (16)	C3—N2—H2B	120 (2)
N1—C2—H2	109.5	C4—C2—H2	109.5
N2—C3—N1	125.4 (2)	H1A—C1—H1B	108.6
N2—C3—S	120.88 (17)	H2A—N2—H2B	124 (3)
C1—C2—C4	110.1 (2)	H3A—O3—H3B	103 (3)
C1—C2—H2	109.5	H5A—O5—H5B	103 (4)
C2—N1—H1	113 (2)	H4A—O4—H4B	101 (4)
S—C1—C2—N1	26.2 (2)	C1—S—C3—N1	8.9 (2)
S—C1—C2—C4	147.72 (17)	C2—N1—C3—N2	−173.2 (2)
O1—C4—C2—N1	11.6 (3)	C2—N1—C3—S	6.7 (3)
O1—C4—C2—C1	−106.0 (3)	C3—S—C1—C2	−20.29 (19)
O2—C4—C2—N1	−169.1 (2)	C3—N1—C2—C1	−22.0 (3)
O2—C4—C2—C1	73.3 (3)	C3—N1—C2—C4	−142.1 (2)
C1—S—C3—N2	−171.2 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O4^i	0.83 (2)	1.94 (2)	2.759 (3)	175 (4)
O5—H5B···O4^ii	0.85 (2)	1.94 (2)	2.787 (3)	174 (4)
O4—H4B···O2	0.84 (2)	1.92 (2)	2.749 (3)	173 (4)
O3—H3A···O1^iii	0.85 (2)	1.97 (2)	2.802 (3)	166 (4)
O3—H3B···O1	0.82 (2)	1.92 (2)	2.731 (3)	169 (3)
O3—H3A···N1^iii	0.85 (2)	2.80 (3)	3.343 (3)	123 (3)
N1—H1···O3^iv	0.85 (2)	1.97 (2)	2.816 (3)	173 (3)
N2—H2A···O2^v	0.87 (2)	1.91 (2)	2.772 (3)	170 (3)
N2—H2B···O1^vi	0.86 (2)	2.98 (3)	3.411 (3)	114 (2)
N2—H2B···O3^vii	0.86 (2)	2.08 (2)	2.862 (3)	152 (3)
C1—H1B···O5	0.97	2.86	3.288 (4)	108
C1—H1B···O4	0.97	2.93	3.640 (3)	131
C1—H1A···O2^i	0.97	2.78	3.744 (4)	175
C2—H2···O2^iv	0.98	2.84	3.637 (3)	140

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