1-Ethyl-4-{2-[1-(4-methyl­phen­yl)ethyl­idene]hydrazinyl­idene}-3,4-dihydro-1H-2λ⁶,1-benzothia­zine-2,2-dione

In the title compound, C₁₉H₂₁N₃O₂S, the dihedral angle between the aromatic rings is 6.7 (2)° and the C=N—N=C torsion angle is 178.0 (2)°. The conformation of the thia­zine ring is an envelope, with the S atom displaced by 0.802 (2) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.022 Å). In the crystal, mol­ecules are linked by C—H...O inter­actions, generating C(5) chains propagating in [010]. A weak C—H...π inter­action is also observed.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.048
• wR factor = 0.139
• Data-to-parameter ratio = 15.7

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N1     --  C7      ..        7.5 su

Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...        3.3 Ratio
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C7
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          2

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          3

   0 ALERT level A = Most likely a serious problem - resolve or explain
   1 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

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

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S1. Comment

As a part of our ongoing studies of benzothiazine derivatives with potential biactivity (Shafiq et al., 2011a,b), we now describe the synthesis and structure of the title compound, (I).

The dihedral angle between the C1–C6 and C13–C18 aromatic rings is 6.68 (15)° and the C10=N2—N3=C11 torsion angle is 177.98 (19)°. The conformation of the C1/C6/C9/C10/N1/S1 thiazine ring is an envelope, with the S atom displaced by 0.802 (2) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.022 Å). A very similar conformation was observed in a related structure (Shafiq et al., 2013). Atoms C7 and C8 in (I) are displaced from the mean plane of the thiazine ring by -0.416 (5) and 0.704 (6) Å, respectively.

In the crystal, the moelcules are linked by C—H···O interactions (Table 1) to generate C(5) chains propagating in the b axis direction. A weak C—H···π interaction to the C13—C18 ring also occurs (Table 1).

Related literature

For the synthesis and biological activity of the title compound and related materials, see: Shafiq et al. (2011a). For further synthetic details, see: Shafiq et al. (2011b). For a related structure, see: Shafiq et al. (2013).

S2. Experimental

4-Hydrazinylidene-1-ethyl-3H-2?6,1-benzothiazine-2,2-dione (Shafiq et al., 2011b) was reacted with para-methyl acetophenone according to literature procedure (Shafiq, et al., 2011a). The product obtained was re-crystallized from ethyl acetate solution to yield yellow prisms.

S3. Refinement

The H atoms were placed in calculated positions (C—H = 0.93–0.97 Å) and refined as riding. The methyl group was allowed to rotate, but not to tip, to best fit the electron density. The constraint U_iso(H) = 1.2U_eq(C) or 1.5U_eq(methyl C) was applied.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of (I), showing displacement ellipsoids at the 50% probability level.

1-Ethyl-4-{2-[1-(4-methylphenyl)ethylidene]hydrazinylidene}-3,4-dihydro- 1H-2λ⁶,1-benzothiazine-2,2-dione

Crystal data

C19H21N3O2S	F(000) = 752
Mr = 355.45	Dx = 1.287 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 335 reflections
a = 15.9018 (10) Å	θ = 3.1–23.5°
b = 7.3716 (4) Å	µ = 0.19 mm^−1
c = 16.8376 (10) Å	T = 296 K
β = 111.644 (3)°	Prism, yellow
V = 1834.57 (19) Å^3	0.34 × 0.26 × 0.24 mm
Z = 4

Data collection

Bruker APEXII CCD diffractometer	3597 independent reflections
Radiation source: fine-focus sealed tube	2598 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
ω scans	θmax = 26.0°, θmin = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −19→18
Tmin = 0.937, Tmax = 0.955	k = −9→8
14168 measured reflections	l = −18→20

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.139	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0649P)^2 + 0.6783P] where P = (Fo^2 + 2Fc^2)/3
3597 reflections	(Δ/σ)max = 0.001
229 parameters	Δρmax = 0.45 e Å^−3
0 restraints	Δρmin = −0.40 e Å^−3

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.53653 (13)	0.1072 (3)	0.23121 (12)	0.0401 (5)
C2	0.62165 (14)	0.1299 (3)	0.22572 (14)	0.0504 (6)
H2	0.6306	0.2260	0.1940	0.060*
C3	0.69200 (16)	0.0146 (4)	0.26570 (16)	0.0610 (7)
H3	0.7478	0.0324	0.2609	0.073*
C4	0.67962 (16)	−0.1279 (4)	0.31306 (17)	0.0629 (7)
H4	0.7274	−0.2057	0.3411	0.076*
C5	0.59694 (17)	−0.1552 (3)	0.31882 (16)	0.0609 (7)
H5	0.5891	−0.2528	0.3504	0.073*
C6	0.52430 (14)	−0.0399 (3)	0.27836 (14)	0.0460 (5)
C7	0.4152 (2)	−0.2572 (4)	0.3072 (2)	0.0795 (9)
H7A	0.3511	−0.2787	0.2768	0.095*
H7B	0.4483	−0.3488	0.2894	0.095*
C8	0.4360 (3)	−0.2746 (6)	0.3986 (3)	0.1315 (16)
H8A	0.4972	−0.2366	0.4293	0.197*
H8B	0.4290	−0.3989	0.4121	0.197*
H8C	0.3954	−0.1999	0.4147	0.197*
C9	0.37033 (14)	0.2050 (3)	0.18892 (14)	0.0478 (5)
H9A	0.3372	0.1275	0.1410	0.057*
H9B	0.3380	0.3191	0.1820	0.057*
C10	0.46398 (13)	0.2394 (3)	0.18915 (12)	0.0411 (5)
C11	0.43384 (14)	0.6397 (3)	0.08403 (13)	0.0451 (5)
C12	0.52607 (16)	0.6781 (3)	0.08357 (17)	0.0603 (6)
H12A	0.5486	0.7891	0.1138	0.090*
H12B	0.5226	0.6896	0.0257	0.090*
H12C	0.5661	0.5804	0.1110	0.090*
C13	0.36016 (14)	0.7729 (3)	0.04561 (13)	0.0443 (5)
C14	0.36872 (17)	0.9137 (3)	−0.00555 (15)	0.0558 (6)
H14	0.4221	0.9255	−0.0157	0.067*
C15	0.30017 (17)	1.0357 (4)	−0.04138 (15)	0.0620 (7)
H15	0.3081	1.1287	−0.0753	0.074*
C16	0.21992 (17)	1.0238 (3)	−0.02836 (14)	0.0553 (6)
C17	0.21100 (16)	0.8847 (3)	0.02377 (14)	0.0532 (6)
H17	0.1578	0.8748	0.0344	0.064*
C18	0.27955 (15)	0.7613 (3)	0.05990 (13)	0.0497 (5)
H18	0.2719	0.6691	0.0943	0.060*
C19	0.1445 (2)	1.1567 (5)	−0.0695 (2)	0.0903 (10)
H19A	0.1632	1.2757	−0.0467	0.135*
H19B	0.0920	1.1212	−0.0580	0.135*
H19C	0.1301	1.1580	−0.1302	0.135*
S1	0.37561 (4)	0.10183 (9)	0.28376 (4)	0.0544 (2)
O1	0.42132 (12)	0.2209 (3)	0.35183 (11)	0.0773 (6)
O2	0.28939 (11)	0.0333 (3)	0.27645 (13)	0.0771 (6)
N1	0.43901 (13)	−0.0742 (3)	0.28385 (14)	0.0600 (6)
N2	0.48467 (12)	0.3786 (3)	0.15443 (12)	0.0536 (5)
N3	0.41244 (13)	0.4972 (3)	0.11660 (12)	0.0546 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0382 (11)	0.0417 (12)	0.0417 (10)	0.0006 (9)	0.0160 (8)	−0.0016 (9)
C2	0.0434 (12)	0.0530 (14)	0.0597 (13)	0.0020 (10)	0.0248 (10)	0.0066 (11)
C3	0.0432 (13)	0.0687 (17)	0.0777 (16)	0.0086 (11)	0.0300 (12)	0.0084 (14)
C4	0.0482 (14)	0.0678 (17)	0.0753 (16)	0.0203 (12)	0.0257 (12)	0.0186 (13)
C5	0.0576 (15)	0.0597 (16)	0.0716 (15)	0.0152 (12)	0.0311 (12)	0.0236 (13)
C6	0.0406 (12)	0.0484 (13)	0.0526 (12)	0.0046 (9)	0.0214 (9)	0.0069 (10)
C7	0.0672 (18)	0.071 (2)	0.109 (2)	−0.0089 (14)	0.0431 (17)	0.0118 (17)
C8	0.167 (4)	0.132 (4)	0.138 (3)	0.049 (3)	0.105 (3)	0.063 (3)
C9	0.0376 (11)	0.0468 (13)	0.0555 (12)	0.0009 (9)	0.0132 (9)	0.0071 (10)
C10	0.0383 (11)	0.0425 (12)	0.0425 (10)	0.0002 (9)	0.0146 (9)	0.0005 (9)
C11	0.0472 (12)	0.0440 (13)	0.0459 (11)	−0.0017 (9)	0.0194 (9)	0.0027 (10)
C12	0.0517 (14)	0.0525 (15)	0.0792 (16)	−0.0029 (11)	0.0272 (12)	0.0070 (13)
C13	0.0477 (12)	0.0415 (12)	0.0425 (10)	−0.0024 (9)	0.0150 (9)	0.0020 (9)
C14	0.0538 (14)	0.0563 (15)	0.0589 (13)	−0.0025 (11)	0.0227 (11)	0.0149 (11)
C15	0.0665 (16)	0.0588 (16)	0.0601 (14)	0.0018 (12)	0.0226 (12)	0.0227 (12)
C16	0.0605 (15)	0.0522 (14)	0.0467 (12)	0.0083 (11)	0.0122 (11)	0.0093 (11)
C17	0.0489 (13)	0.0597 (15)	0.0511 (12)	0.0041 (11)	0.0186 (10)	0.0026 (11)
C18	0.0528 (13)	0.0472 (13)	0.0492 (12)	−0.0005 (10)	0.0191 (10)	0.0074 (10)
C19	0.083 (2)	0.099 (2)	0.089 (2)	0.0348 (18)	0.0322 (17)	0.0373 (19)
S1	0.0401 (3)	0.0653 (4)	0.0638 (4)	0.0066 (3)	0.0262 (3)	0.0137 (3)
O1	0.0671 (12)	0.1064 (16)	0.0636 (10)	0.0069 (10)	0.0302 (9)	−0.0119 (10)
O2	0.0449 (10)	0.0878 (13)	0.1101 (15)	0.0094 (9)	0.0422 (10)	0.0334 (11)
N1	0.0461 (11)	0.0570 (13)	0.0836 (14)	0.0062 (9)	0.0316 (10)	0.0266 (11)
N2	0.0456 (11)	0.0509 (12)	0.0679 (12)	0.0070 (8)	0.0251 (9)	0.0179 (10)
N3	0.0481 (11)	0.0499 (12)	0.0687 (12)	0.0076 (9)	0.0249 (9)	0.0193 (10)

Geometric parameters (Å, º)

C1—C6	1.399 (3)	C11—N3	1.287 (3)
C1—C2	1.400 (3)	C11—C13	1.482 (3)
C1—C10	1.477 (3)	C11—C12	1.497 (3)
C2—C3	1.368 (3)	C12—H12A	0.9600
C2—H2	0.9300	C12—H12B	0.9600
C3—C4	1.376 (3)	C12—H12C	0.9600
C3—H3	0.9300	C13—C14	1.387 (3)
C4—C5	1.368 (3)	C13—C18	1.391 (3)
C4—H4	0.9300	C14—C15	1.370 (3)
C5—C6	1.393 (3)	C14—H14	0.9300
C5—H5	0.9300	C15—C16	1.375 (3)
C6—N1	1.416 (3)	C15—H15	0.9300
C7—C8	1.456 (5)	C16—C17	1.391 (3)
C7—N1	1.493 (3)	C16—C19	1.505 (3)
C7—H7A	0.9700	C17—C18	1.377 (3)
C7—H7B	0.9700	C17—H17	0.9300
C8—H8A	0.9600	C18—H18	0.9300
C8—H8B	0.9600	C19—H19A	0.9600
C8—H8C	0.9600	C19—H19B	0.9600
C9—C10	1.509 (3)	C19—H19C	0.9600
C9—S1	1.742 (2)	S1—O1	1.4135 (19)
C9—H9A	0.9700	S1—O2	1.4233 (17)
C9—H9B	0.9700	S1—N1	1.643 (2)
C10—N2	1.282 (3)	N2—N3	1.397 (2)
C6—C1—C2	118.04 (19)	C11—C12—H12A	109.5
C6—C1—C10	122.43 (18)	C11—C12—H12B	109.5
C2—C1—C10	119.52 (19)	H12A—C12—H12B	109.5
C3—C2—C1	121.9 (2)	C11—C12—H12C	109.5
C3—C2—H2	119.1	H12A—C12—H12C	109.5
C1—C2—H2	119.1	H12B—C12—H12C	109.5
C2—C3—C4	119.6 (2)	C14—C13—C18	117.4 (2)
C2—C3—H3	120.2	C14—C13—C11	121.6 (2)
C4—C3—H3	120.2	C18—C13—C11	120.97 (19)
C5—C4—C3	120.0 (2)	C15—C14—C13	121.4 (2)
C5—C4—H4	120.0	C15—C14—H14	119.3
C3—C4—H4	120.0	C13—C14—H14	119.3
C4—C5—C6	121.4 (2)	C14—C15—C16	121.5 (2)
C4—C5—H5	119.3	C14—C15—H15	119.3
C6—C5—H5	119.3	C16—C15—H15	119.3
C5—C6—C1	119.1 (2)	C15—C16—C17	117.7 (2)
C5—C6—N1	120.1 (2)	C15—C16—C19	120.9 (2)
C1—C6—N1	120.82 (18)	C17—C16—C19	121.4 (2)
C8—C7—N1	112.2 (3)	C18—C17—C16	121.2 (2)
C8—C7—H7A	109.2	C18—C17—H17	119.4
N1—C7—H7A	109.2	C16—C17—H17	119.4
C8—C7—H7B	109.2	C17—C18—C13	120.9 (2)
N1—C7—H7B	109.2	C17—C18—H18	119.6
H7A—C7—H7B	107.9	C13—C18—H18	119.6
C7—C8—H8A	109.5	C16—C19—H19A	109.5
C7—C8—H8B	109.5	C16—C19—H19B	109.5
H8A—C8—H8B	109.5	H19A—C19—H19B	109.5
C7—C8—H8C	109.5	C16—C19—H19C	109.5
H8A—C8—H8C	109.5	H19A—C19—H19C	109.5
H8B—C8—H8C	109.5	H19B—C19—H19C	109.5
C10—C9—S1	110.92 (14)	O1—S1—O2	118.78 (12)
C10—C9—H9A	109.5	O1—S1—N1	110.96 (11)
S1—C9—H9A	109.5	O2—S1—N1	106.91 (11)
C10—C9—H9B	109.5	O1—S1—C9	107.98 (12)
S1—C9—H9B	109.5	O2—S1—C9	110.88 (10)
H9A—C9—H9B	108.0	N1—S1—C9	99.65 (11)
N2—C10—C1	117.42 (19)	C6—N1—C7	121.4 (2)
N2—C10—C9	123.51 (19)	C6—N1—S1	117.47 (16)
C1—C10—C9	119.07 (18)	C7—N1—S1	119.90 (17)
N3—C11—C13	115.83 (19)	C10—N2—N3	113.76 (18)
N3—C11—C12	124.8 (2)	C11—N3—N2	113.78 (19)
C13—C11—C12	119.40 (19)
C6—C1—C2—C3	−0.8 (3)	C15—C16—C17—C18	−1.1 (3)
C10—C1—C2—C3	177.9 (2)	C19—C16—C17—C18	178.7 (2)
C1—C2—C3—C4	−0.2 (4)	C16—C17—C18—C13	0.3 (3)
C2—C3—C4—C5	1.0 (4)	C14—C13—C18—C17	0.5 (3)
C3—C4—C5—C6	−0.8 (4)	C11—C13—C18—C17	−179.7 (2)
C4—C5—C6—C1	−0.3 (4)	C10—C9—S1—O1	61.17 (18)
C4—C5—C6—N1	178.5 (2)	C10—C9—S1—O2	−167.11 (16)
C2—C1—C6—C5	1.1 (3)	C10—C9—S1—N1	−54.73 (18)
C10—C1—C6—C5	−177.7 (2)	C5—C6—N1—C7	−19.6 (4)
C2—C1—C6—N1	−177.7 (2)	C1—C6—N1—C7	159.1 (2)
C10—C1—C6—N1	3.6 (3)	C5—C6—N1—S1	147.7 (2)
C6—C1—C10—N2	173.5 (2)	C1—C6—N1—S1	−33.5 (3)
C2—C1—C10—N2	−5.2 (3)	C8—C7—N1—C6	92.8 (3)
C6—C1—C10—C9	−6.5 (3)	C8—C7—N1—S1	−74.3 (3)
C2—C1—C10—C9	174.75 (19)	O1—S1—N1—C6	−57.8 (2)
S1—C9—C10—N2	−144.76 (19)	O2—S1—N1—C6	171.25 (17)
S1—C9—C10—C1	35.3 (2)	C9—S1—N1—C6	55.80 (19)
N3—C11—C13—C14	−167.5 (2)	O1—S1—N1—C7	109.8 (2)
C12—C11—C13—C14	13.1 (3)	O2—S1—N1—C7	−21.2 (2)
N3—C11—C13—C18	12.7 (3)	C9—S1—N1—C7	−136.6 (2)
C12—C11—C13—C18	−166.7 (2)	C1—C10—N2—N3	−179.62 (17)
C18—C13—C14—C15	−0.7 (3)	C9—C10—N2—N3	0.4 (3)
C11—C13—C14—C15	179.6 (2)	C13—C11—N3—N2	−178.06 (18)
C13—C14—C15—C16	−0.1 (4)	C12—C11—N3—N2	1.3 (3)
C14—C15—C16—C17	1.0 (4)	C10—N2—N3—C11	177.98 (19)
C14—C15—C16—C19	−178.8 (3)

Hydrogen-bond geometry (Å, º)

Cg3 is the centroid of the C13–C18 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···O2^i	0.97	2.50	3.402 (4)	155
C9—H9A···Cg3^ii	0.97	2.67	3.613 (2)	165

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