Treatment of 2-(benzo[d]thiazol-2’-ylthio)acetohydrazide (3) with acetylacetone afforded N-(4-oxopentan-2-ylidine) acetohydrazide derivative 5. The acetohyrazide derivatives 3 and 5 were utilized as a key intermediate for the synthesis of a novel heterocyclic compounds. The synthesis of a novel series of condensation and substituted derivatives of 2-(benzo[ d]thiazol-2’-ylthio) acetohydrazide in good yield has been reported. The newly synthesized compounds were characterized by elemental analysis 1H-NMR, 13C-NMR spectra and X-ray crystallographic investigations. The reported crystal structures of these novel 2-(benzo[d] thiazol-2’-ylthio)acetohydrazide derivatives are expected to be a remarkable contribution to the crystallographic database of heterocyclic compounds.
Benzothiazole and its derivatives represent one of the most biologically active classes of compounds, displaying a remarkable diversity of bioactivities in the medical and the agrochemicals field [
The 2-(benzo[d]thiazol-2’-ylthio) acetohydrazide (3) proved to be a useful key intermediate in the synthesis of several heterocyclic nuclei [
Scheme 1. Synthesis route of 2-(benzo[d]thiazol-2’-ylthio) acetohydrazide and their derivatives.
these protons are in a different environment. Likewise, the 1H NMR spectrum exhibited two singlet signals at δH 4.58 and 10.70 ppm for -SCH2-protons and NH group respectively. The assignments of 1H and 13C chemical shifts of compound 5 were registered in the Experimental Section. On the other hand, when the compound 5 heated in ethanol, containing a catalytic amount of piperidine, afforded 5-hydroxy-4, 5-dihydropyrazole derivative 6 in good yield. The mass spectrum of the obtained product revealed a molecular ion peak [M+] at m/z 321[15%] and it is compatible with the molecular formula C14H15N3O2S2. It is worth mentioning that both compounds 5 and compound 6 have the same molecular formula, but has different melting points and spectral data (cf. Scheme 1). The complete assignments of 1H and 13C chemical shift for 6 based on COSY and HSQC were recorded in the Experimental Section. The structure of compound 6 was established based on X-ray crystallographic analysis, the pyrazole ring containing the chiral center (at C 10) and the benzothiazole moiety has located almost the same plane (cf.
Moreover, treatment of acetohydrazide derivative 5 with malononitrile in refluxing ethanolic piperidine afforded the [1,2,4]-triazolo[1,5-a]pyridine derivative 9 in good yield via the intermediary 7-8 (cf. Scheme 1).
Analytical and spectroscopic data confirmed the structure of compound 9. The mass spectrum of 9 revealed the molecular ion peak (which is the base peak as well) at m/z value 351 [M+, 100%]. The complete assignments of the 1H and 13C chemical shift of the compound were recorded in the Experimental Section. It is worth noting that recently, [1,2,4]-triazolopyridine derivatives have been shown to be useful antifungal activities compare with the commercial pesticide [
On the other hand, treatment of acetohydrazide derivative 3 with 2,3-butanedione in refluxing ethanolic piperidine afforded the acetohydrazide derivative 10 in good yield (cf. Scheme 2). The analytical and spectral data of the last reaction product are entirely consistent with the proposed structure. The complete assignments of 1H and 13C chemical shifts of compound 10 based on COSY and HSQC experiments were recorded in the Experimental Section. Moreover, Nuclear Overhauser Effect (NOE) experiments were carried out to establish the configuration of acetohydrazide derivatives 10 whether it is (E) or (Z)isomers. Therefore, irradiation of a signal of the NH proton at δH 11.40 ppm,we observed increasing a signal of the methyl protons at δH 1.95 ppm. While, irradiation of a methyl signal at δH 1.95 ppm, increased the a NH signal at δH 11.40 ppm and have no effect on an acetyl signal at δH 2.41 ppm. Indicate the 2-(benzo[d]thiazol-2’-ylthio)acetamide moiety and the methyl group
Bond | Bond length (˚A) | Bond | Bond angle (˚) |
---|---|---|---|
S2-C7 | 1.734 (2) | C7-S2-C8 | 102.27 (11) |
O2-C10 | 1.404 (3) | N3-C13-C14 | 121.3 (3) |
C14-C13 | 1.487 (4) | C13-N3-N2 | 107.3 (2) |
C13-N3 | 1.279 (3) | C9-N2-C10 | 125.35 (19) |
N3-N2 | 1.399 (3) | O2-C10-C11 | 111.2 (2) |
N2-C10 | 1.491 (3) | N2-C10-C12 | 99.30 (19) |
Scheme 2. Reactions of 2-(benzo[d]thiazol-2’-ylthio) acetohydrazide with carbonyl compounds and phthalic anhydride.
are on opposite sides of the C=N, as required by an (E)-form. The crystal structure of 10 [
Moreover, treatment of 2-(benzo[d]thiazol-2’-ylthio) acetohydrazide 3 with phthalic anhydride in refluxing acetic acid, afforded N-(1,3-dioxoisoindolin-2-yl)acetamide derivative 13 in good yield and not 2,3-dihy- drophthalazine-1,4-dione derivative 12 as it reported in the literature [
On the other hand, condensation of 2-(benzo[d]thiazol-2’-ylthio) acetohydrazide (3) with 1,3-cyclohexadione yielded N’-(3-oxocylohex-1-enyl) acetohydrazide hydrate derivative (15) as depicted in Scheme 2. The structure
Bond | Bond length (˚A) | Bond | Bond angle (˚) |
---|---|---|---|
S2-C5 | 1.804 (2) | C4-S2-C5 | 100.69 (10) |
N1-C6 | 1.356 (3) | C6-N1-H1A | 120.7 |
N1-N2 | 1.364 (3) | C7-N2-N1 | 117.4 (2) |
N2-C7 | 1.282 (3) | C6-C5-S2 | 106.32 (15) |
C5-C6 | 1.505 (3) | O1-C8-C11 | 122.5 (3) |
C7-C8 | 1.497 (4) | N2-C7-C10 | 126.8 (3) |
Bond | Bond length (˚A) | Bond | Bond angle (˚) |
---|---|---|---|
S1-C7 | 1.7439 (16) | C7-S1-C8 | 101.81 (8) |
O1-C9 | 1.204 (2) | N3-N2-H2 | 120.3 |
N2-N3 | 1.3788 (19) | C9-C8-S1 | 114.52 (11) |
C8-H8A | 0.97 | C1-S2-C7 | 88.69 (8) |
O3-C17 | 1.205 (2) | O1-C9-N2 | 122.94 (15) |
C9-C8 | 1.512 (2) | O2-C10-C11 | 130.31 (16) |
of this acetohydrazide hydrate derivative (15) deduced from its elemental analysis and spectroscopic data. The mass spectrum revealed a molecular ion peak at m/z 333[M+ -H2O], which corresponds to a molecular weight consistent with a formula of C15H15N3O2S2 (cf. Experimental Section). Furthermore, the X-ray crystallography provided an unambiguous evidence of structure 15 as proposed in Scheme 2 [
The single crystal of 15 also contains water molecules in its network as space filling solvent. Based on bond length (
Bond | Bond length (˚A) | Bond | Bond angle (˚) |
---|---|---|---|
O1-C9 | 1.214 (6) | N3-N2-C9 | 119.7 (4) |
O2-C12 | 1.249 (6) | C10-C11-C12 | 120.6 (4) |
N2-C9 | 1.346 (6) | O2-C12-C13 | 120.5 (6) |
N3-C10 | 1.318 (7) | O1-C9-C8 | 123.8 (4) |
C10-C11 | 1.426 (6) | C11-C10-C15 | 120.8 (5) |
C11-C12 | 1.422 (8) | C10-N3-H3A | 118.9 |
In continuation of our efforts to generate new routes to the different functional thiophenes [
On the other hand, treatment of acetohydrazide derivative 3 with triethyl orthoformate, in refluxing acetic anhydride afforded N’-(acetyl) acetohydrazide derivative 19. In a similar manner, upon treatment of acetohydrazide derivative 3 with chloroacetyl chloride in dimethylformamide (DMF), afforded the N’-(2-chloroacetyl)- acetohydrazide derivative 20 in good yield. The structure of 20 also confirmed by its spectral data. It should remark at this point that many publications have recently reported the broad spectrum of biological usefulness exhibited by N, N-diacylhydrazine derivatives such as anti-HIV, herbicidal and antifungal activities [
Scheme 3. Reactions of compound 3 with HC(OEt)3/Ac2O, ClCH2COCl, cinnamoly chloride, PhNCS and DMAD.
Moreover, the 1H-NMR spectrum showed in addition to the expected aromatic signals, two downfield signals at δH 11.74 and 11.44 ppm and two upfield signals at δH 4.71 and 4.45 ppm assignable to the E and Z-configu- ration for NH and methylene protons respectively. The crystal structure, bond lengths and bond angles data of 23 [
Melting points are reported uncorrected and determined on a Gallenkamp apparatus. The Infrared spectra recorded on a Jasco FT/IR-6300 FT-IR uses KBr disks. 1H-NMR and 13C-NMR spectra were measured on a Bruker DPX 400 MHz and Bruker AVANCE ΙΙ 600 MHz spectrometers, with DMSO-d6 or CDCl3 as solvent using TMS as an internal standard. The methods used for the purpose of NMR assignment were COSY, HSQC, DEPT and NOE. The chemical shifts expressed as a δ unit in parts per million (ppm) and TMS = 0.00 ppm. The following abbreviation is used: s = singlet, d = doublet, t = triplet; q = quartet; m = multiple; br. = broad. Mass spectra measured on GC/MS DFS, THERMO instrument. Microanalyses performed on a CHNS-Vario.
Micro Cube Analyzer; Single crystal X-ray crystallography was performed using Rigaku Rapid ΙΙ and Bruker X8 Prospector diffractometers. The starting materials ethyl-2-(benzo[d]thiazol-2’-ylthio) acetate 2, mp 59˚C (lit.
Bond | Bond length (˚A) | Bond | Bond angle (˚) |
---|---|---|---|
N2-C9 | 1.359 (6) | S2-C8-C9 | 109.3 (3) |
O2-C12 | 1.205 (11) | O1-C9-N2 | 120.5 (4) |
N2-N3 | 1.348 (4) | O2-C12-C11 | 116.6 (6) |
N3-C10 | 1.285 (6) | O5-C14-C10 | 115.2 (4) |
C10-C14 | 1.478 (5) | C9-N2-H2A | 120.9 |
C11-C12 | 1.536 (8) | C10-C11-C12 | 114.8 (5) |
mp. 58˚C) [
A mixture of compound 3 (2.39 gm 10.0 mmol) and 2,4-pentanedione (1.0 g, 10 mmol) in ethanol (20 mL) was refluxed for 3 h. The reaction was allowed to cool to room temperature for 24 h. The solid product formed was collected by filtration and crystallized from ethanol as white crystal. Yield: 2.40 g (75%); mp 182˚C - 184˚C; FT-IR vmax (cm−1): 3186 - 3568 (br, NH), 1690 (C=O ketone),1670(C=O amide); 1H NMR (DMSO-d6) δ ppm: 10.7 (s, 1H, NH, D2O exchangeable ), 8.02 (d, J = 8 Hz, 1H, H-4’), 7.85 (d, J = 8 Hz, 1H, H-7’), 7.46 (t, J = 8 Hz, 1H, H-6’), 7.36 (t, J = 8 Hz, 1H, H-5’), 4.58 (s, 2H, -SCH2), 2.97 (d, J = 16, 1H, H-3), 2.84 (d, J = 16, 1H, H-3a), 2.01 (s,3H, CH3), 1.77 (s, 3 H, CH3); 13C NMR (DMSO-d6) δ ppm: 168.1 (C=O), 166.4 (C=O), 165.1(C-2’), 155.9 & 152.6 (C-2 &C-3a’), 135.1 (C-7a’), 126.4 (C-6’), 124.6 (C-5’), 121.9 (C-4’), 121.2 (C-7’), 52.2 ( CH2), 37.9 (CH2), 23.0 (CH3), 14.1 (CH3). EI-MS m/z [relative intensity]: 321 [M+, 10], 264 [15%], 208 [100%], 180 [62%]. Anal. Calcdfor C14H15N3O2S2 (321.42): C, 52.32; H, 4.70; N, 13.07%. Found: C, 52.16; H, 4.53; N, 13.39%.
A solution of 5 (3.21 g, 10 mmol ) in ethanol (20 mL) containing a few drops of piperidine was refluxed for 3 h. The reaction was allowed to cool to room temperature for 24 h. The solid product formed, was collected by filtration and crystallized from ethanol as yellow crystal. Yield: 2.34 g (73%); mp 123˚C - 125˚C; FT-IR vmax (cm−1): 3090 - 3998 (br, OH), 1670(C=O); 1H NMR (DMSO-d6) δ ppm: 7.90 (d, J = 8 Hz, 1H, H-4’), 7.78 (d, J = 8 Hz, 1H, H-7’), 7.47 (t, J = 8 Hz, 1H, H-6’), 7.31 (t, J = 8 Hz, 1H, H-5’), 6.55 (s, 1H, OH, D2O exchangeable), 4.58 (dd, J = 20, 2H, SCH2), 2.98 (d, J = 16, 1H, H-4 pyrazole), 2.82 (d, J = 16, 1H, H-4’pyrazole), 2.01 (s, 3H, CH3), 1.76 (s, 3 H, CH3); 13C NMR ( DMSO-d6) δ ppm: 166.5 (C=O), 163.7 (C-2’), 155.8 (C-3), 152.7 (C-3a’), 134.7 (C-7a’), 126.4 (C-6’), 124.4 (C-5’), 121.8 (C-4’), 121.1 (C-7’), 90.7 (C-5 pyrazole), 52.2 (C-4pyrazole), 37.9 (SCH2),), 25.9 (CH3), 15.9 (CH3). EI-MS m/z [relative intensity]: 321 [M+, 15%], 264 [18%], 230 [3%], 208 [100%], 180 [62%]. Anal. Calcdfor C14H15N3O2S2 (321.42): C, 52.32; H, 4.70; N, 13.07%. Found: C, 52.21; H, 4.55; N, 13.08%.
A mixture of 5 (3.21 g, 10.0 mmol) and malononitrile (0.66 g, 10 mmol) in ethanol (20 mL) containing a few drops of piperidine was refluxed for 4 h. The reaction was allowed to cool to room temperature. The solid product formed, was collected by filtration and crystallized from ethanol as brown crystals. Yield: 2.56 g (73%); mp 258˚C - 260˚C; FT-IR vmax (cm−1): 2227 (CN); 1H-NMR (DMSO-d6) δ ppm: 7.94 (d, J = 8 Hz, 1H, H-4’), 7.84 (d, J = 8 Hz, 1H, H-7’), 7.47 (t, J = 8 Hz, 1H, H-6’), 7.36 (t, J = 8 Hz, 1H, H-5’), 7.10 (s,1H, 6-H pyridine), 4.18 (s,2H, SCH2), 2.29 (s,, 3 H, CH3), 2.21 (s, 3 H, CH3); 13C NMR (DMSO-d6) δ ppm: 163.4, 160.7, 153.1, 151.6, 149.5, 143.5, 135.5, 126.8, 125.1, 122.2, 121.8, 116.3, 114.4, 107.8 (arom. Carbons & CN), 30.7 (SCH2), 20.0 (CH3), 17.9 (CH3). EI-MS m/z (relative intensity): 351 [M+, 100%], 318 [23%], 274 [2%], 236 [4%]. Anal. Calcd. for C17H13N5S2 (351.45): C, 58.10; H, 3.73; N, 19.93; Found: C, 58.18; H, 3.83; N, 19.73.
A mixture 3 (2.39 g, 10.0 mmol) and 2,3-butanedione (0.87 g, 10.0 mmol) in ethanol (20 mL) containing a few drops of piperidinewas refluxed for 1 h. The reaction mixture was allowed to cool to room temperature. The product formed was collected by filtration and recrystallized from ethanol as yellow crystals. Yield: 2.64 g (86%); mp 198˚C - 199˚C. FT-IR vmax (cm−1): 3188 - 3448 (br, NH), 1680 (C=O ketone), 1612 (C=O amide); 1H NMR (DMSO-d6) δ ppm: 11.40 (s, 1H, NH, D2O exchangeable), 8.02 (d, J = 8 Hz, 1H, H-4’) 7.81 (d, J = 8 Hz, 1H, H-7’), 7.46 (t, J = 8 Hz, 1H, H-6’), 7.36 (t, J = 8Hz, 1H, H-5’), 4.75 (s, 2H, SCH2), 2.41(s, 3H, COCH3), 1.95 (s, 3H, CH3); 13C NMR (DMSO-d6) δ ppm: 196.9 (C=O ketone), 169.8 (C=O amide), 166.0 (C-2’), 152.4 (C-3a’), 147.4 (C-2), 134.7 (C-7a’), 126.3 (C-6’), 124.6 (C-5’), 121.9 (C-4’), 121.1 (C-7’), 35.3 (SCH2), 24.3 (COCH3), 9.8 (CH3). EI-MS m/z [relative intensity]: 307 [M+, 10%], 264 [100%], 231 [13%], 208 [11%]. Anal. Calcd. for C13H13N3O2S2 (307.39): C, 50.79; H, 4.26; N, 13.67%. Found: C, 50.53; H, 4.39; N, 13.45%.
A mixture of 3 (2.39 g 10.0 mmol) and phthalic anhydride (1.48 g, 10 mmol ) in acetic acid (10 mL) was heated under refluxed for 2 - 3 h. The solid product, so formed, was collected by filtration and recrystallized from 1,4-dioxane as white crystal solid. Yield: 2.69 mg (73%); mp 176˚C - 178˚C; FT-IR vmax (cm−1): 3215 (br, NH), 1793 & 1743 (2C=O),1662 (C=O amide); 1H NMR (DMSO-d6) δ ppm : 11.22 (s, 1H, NH, D2O exchangeable), 8.01 (d, J =8 Hz, 1H, H-4’) ,7.94 (d, J = 7.4 Hz, 2H, H-4 & H-7), 7.93 (d, J = 8 Hz, 1H, H-7’), 7.91 (t, J = 7.4 Hz, 2H, H-5 & H-6), 7.48 (t, J = 8 Hz, 1H, H-6’), 7.37 (t, J = 8 Hz, 1H, H-5’), 4.49 (s, 2H, SCH2); 13C NMR (DMSO-d6) δ ppm: 166.5 (2C=O amide ) 165.3 (C=O amide ), 164.9 (C-2’), 152.5 (C-3a’), 135.2 (C-5 & C6), 134.9 (C-7a’), 129.4 (C-4a & C-7a), 126.4 (C-6’), 124.5 (C-5’), 123.7 (C-4 & C-7), 121.8 (C-4’), 121.3 (C-7’), 34.3 (SCH2). EI-MS m/z [relative intensity]: 369 [M+, 295 [11%], 250 [9%], 208 [100%]. Anal. Calcd. for C17H11N3O3S2 (369.42): C, 55.27; H, 3.00; N, 11.37%. Found: C, 54.90; H, 3.00; N, 11.22%.
A mixture of 3 (2.39 g 10.0 mmol) and 1,3-cyclohexanedione (1.12 g, 10.0 mmol) in ethanol (20 mL) was refluxed for 2 - 3 h. The reaction mixture was allowed to cool to room temperature. The product formed was collected by filtration and recrystallized from ethanol as yellow crystals. Yield: 2.63 g (79%); mp 185˚C - 187˚C; FT-IR vmax (cm−1):3433 (OH), 3198 (NH), 1695(C=O), 1657 (C=O); NMR (DMSO-d6) δ ppm: 10.29 (s, 1H, NH, D2O exchangeable), 8.96 (s, 1H, NH, D2O exchangeable), 8.02 (d, J = 8 Hz, 1H, H-4’), 7.96 (d, J = 8 Hz, 1H, H-7’), 7.47 (t, J = 8 Hz, 1H, H-6’), 7.37 (t, J = 8 Hz, 1H, H-5’), 5.15 (s, 1H, H-2) 4.23 (s, 2H, SCH2), 2. 32 (t, J = 8, 2 H, H-4), 2.11 (t, J = 8, 2 H, H-6) 1.8 (t , J = 8, 2H, H-5); 13C NMR (DMSO-d6) δ ppm: 196.2 (C=O ketone), 170.5 (C=O amide), 166.0 (C-2), 164.6 (C-1), 152 (C-3a’), 135.1 (C-7a’), 126.0 (C-6’), 124.0 (C-5’), 122.1 (C-4’), 121 (C-7’), 99.7 (C-2), 37.1 (SCH2), 26.0 (C-4), 22.1 (C-6), 19.2 (C-5). EI-MS m/z [relative intensity]: 333 [M+-H2O, 10%], 315 [7%], 223 [3%], 208 [47%], 180 [56%]. Anal.Calcd.for C15H17N3O3S2 (351.34): C, 51.26; H, 4.88; N, 11.92%. Found: C, 51.08; H, 4.74; N, 11.92%.
A mixture of 3 (2.39 g, 10.0 mmol), and thiophene-2-carbaldehyde (1.12 g, 10.0 mmol) in methanol (20 mL) was refluxed for 1 h. The reaction mixture was allowed to cool to room temperature. The product formed was collected by filtration and crystallized from ethanol as yellow crystals. Yield: 2.53 g (76%); mp 134˚C - 136˚C; FT-IR vmax (cm−1): 3295 (NH); 1658 (CO); 1H-NMR (DMSO-d6) δ ppm: 11.74 (s, 1H, D2O exchangeable, NH), 8.25 (s, 1 H, HC=N), 7.10 - 8.00 (m, 7H, Ar-H), 4.63 (s, 2H, SCH2); 13C NMR (DMSO-d6) δ ppm: 167.9 (C=O), 165.3 (C-2’), 152.5 (-3a’), 142.4, 139.1, 134.8, 131.3, 130.7, 128.7, 127.8, 126.3, 124.4, 121.8 (arom. & HC=N), 35.8 (SCH2). EI-MS m/z [relative intensity]: 333 [M+, 12%], 259 [4%], 223 [3%], 208 [100%], 180 [71%]. Anal. Calcd. for C14H11N3OS3 (333.38): C, 50.43; H, 3.33; N, 12.60%. Found: C, 50.33; H, 3.27; N, 12.61%.
A mixture of 3 (2.39 g 10.0 mmol) and triethyl orthoformate (1.6 g, 10.0 mmol) in acetic anhydride (20 mL) was refluxed for 2 h. The reaction was allowed to cool to room temperature, then poured in ice cold water. The solid product formed was collected by filtration and crystallized from ethanol as white crystals. Yield: 1.9 g (71%); mp 202˚C - 204˚C; FT-IR vmax (cm−1): 3205 (2NH), 1685, 1641 (2C=O amide);1H-NMR (DMSO-d6) δ ppm: 10.28 (s, 1H, NH, D2O exchangeable), 9.99 (s, 1H, NH, D2O exchangeable), 8.02 (d, J = 8 Hz, 1H, H-4’), 7.85 (d, J = 8 Hz, 1H, H-7’), 7.48 (t, J = 8 Hz, 1H, H-6’), 7.38 (t, J = 8Hz, 1H, H-5’), 4.23 (s, 2H, SCH2), 1.92 (s, 3H, CH3); 13C-NMR (DMSO-d6): δC 167.9 (C=O), 165.9 (C=O), 165.4 (C-2’), 152.5 (C-3a’), 134.8 (C-7a’), 126.4 (C-6’), 124.6 (C-5’), 121.9 (C-4’), 121.2 (C-7’), 34.7 (SCH2), 20.5 (CH3). EI-MS m/z [relative intensity]: 281 [M+, 12%], 236 [4%], 208 100%], 180 [37%]. Anal. Calcd. for C11H11N3O2S2 (281.35): C, 46.96; H, 3.94; N, 14.93%. Found: C, 46.81; H, 3.95; N, 14.92%.
A mixture 3 (2.39 g, 10.0 mmol) and chloroacetyl chloride (1.12 g, 10.0 mmol) in DMF (20 mL) was heated for 2 h. The mixture was allowed to cool to room temperature. The solid product formed was collected by Filtration and crystallized from ethanol as yellow crystals. Yield: 2.28 g (82%); mp 162˚C - 164˚C; FT-IR vmax (cm−1): 3174 (2NH), 1659 (2C=O amide); 1H-NMR (DMSO-d6) δ ppm: 10.56 (s, 1H, NH, D2O exchangeable) 10.52 (s, 1H,NH, D2O exchangeable), 8.03 - 7.35 (m, 4H, ArH), 4.52 (s, 2H, CH2), 4.26 (s, 2H, CH2); 13C-NMR (DMSO- d6) δC ppm: 165.7 (C=O), 165.3 (C=O), 162.3 (C-2’), 152.5 (C-3a’), 135.8 (C-7a’), 126.4 (C-6’), 124.6 (C-5’), 121.8 (C-4’), 121.2 (C-7’), 40.8 (CH2Cl), 34.6 (SCH2). EI-MS m/z [relative intensity]: 316 [M+, 13%], 279 [2%], 241 [2%], 208 [100%]. Anal. Calcd. for C11H10ClN3O2S2 (315.80): C, 41.84; H, 3.19; N, 13.31%. Found: C, 41.72; H, 3.23; N, 13.43%.
A mixture of 3 (2.39 g 10.0 mmol) and cinnamoyl chloride (1.66 g, 10.0 mmol) in 1,4 dioxane (20 mL) containing a few drops of triethylamine was refluxed for 2 h .The solid product formed, was collected by filtration and crystallized from ethanol as white crystals. Yield: 2.80 g (76%); mp 164˚C - 166˚C; FT-IR vmax (cm−1): 3207 (2NH), 1672 (C=O), 1641 (CO-amide); 1H-NMR (DMSO-d6) δH: 10.60 (s, 1H,NH, D2O exchangeable), 10.39 (s, 1H, NH, D2O exchangeable), 8.03 (d, J = 8 Hz, 1H, H-4’), 7.87 (d, J = 8 Hz, 1H, H-7’), 7.88 - 7.37 (m, 8H, Ar-H & vinylic-H), 6.70 (d, 1H, J = 16, vinylic-H), 4.28 (s, 2H, SCH2); 13C-NMR (DMSO-d6) δC ppm: 165.8 & 165.0 (2C=O), 163.3, 152.5, 140.3, 134.8, 134.5, 129.8, 129.0, 127.7, 126.4, 124.6, 121.8, 121.2, 119.2 (arom. carbons) 34.7 (CH2). EI-MS m/z [relative intensity]: 369 [M+, 7%], 208 [51%] 180 [9%], 148 [3%], 131 [100%]. Anal. Calcd. for C18H15N3O2S2 (369.46): C, 58.52; H, 4.09; N, 11.37%. Found: C, 58.32; H, 4.09; N, 11.39%.
A mixture of 3 (2.39 g 10.0 mmol) and phenyl isothiocyanate (1.99 g, 10.0 mmol) in ethanol (20 mL) and sodium hydroxide solution (2 g in 20 mL water) was refluxed for 2 h. The reaction mixture was allowed to cool to room temperature then acidify with 10% HCl. The product formed was collected by filtration and crystallized from ethanol as yellow crystals. Yield: 2.99 g (84%); mp 140˚C - 142˚C; FT-IR vmax (cm−1): 3061(NH); 1H-NMR (DMSO-d6) δH ppm: 7.17 - 7.95 (m, 10H, ArH & NH), 4.54 (s, 2H, SCH2). EI-MS [relative intensity]: 356 [M+, 71%], 323 [8%] 265 [3%], 224 [7%].190 [12%]. Anal. Calcd. for C16H12N4S3 (356.46): C 53.91; H, 3.39; N, 15.72%. Found: C, 53.97; H, 3.46; N, 15.92%.
Mixture of 3 (2.39 g, 10.0 mmol) and dimethylacetylene dicarboxylate (1.12 g, 10.0 mmol) in 1,4 dioxane (20 mL) containing a few drops of triethylamine was refluxed for 3 h. The mixture was allowed to cool to room temperature. The solid product formed, was collected by filtration and crystallized from methanol as pale yellow crystals. Yield: 2.85 g (75%); mp 147˚C - 148˚C; FT-IR vmax (cm−1): 3182 (NH), 1749,1710 (2C=O ester), 1683 (C=O amide); 1H NMR (DMSO-d6) δppm: 11.74 (s, 1H, NH, D2O exchangeable), 7.98 (d, J = 8 Hz, 1H, H-4’), 7.84 (d, J = 8 Hz, 1H, H-7’), 7.45 (t, J = 8 Hz, 1H, H-6’), 7.35 (t, J = 8 Hz, 1H, H-5’), 4.71 (s, 2H, SCH2), 3.83 (s, 2H, CH2), 3.82 (s, 3H, OCH3), 3.67 (s, 3H, OCH3); 13C-NMR (DMSO-d6) δC/ppm: 170.0 (amide C=O), 166.4 (ester C=O), 165.2 (ester C=O), 164.5 (C-2’), 152.9 (C-3a’), 136.3 (C=N), 135.2 (C-7a’), 126.8 (C-6’), 125.0 (C-5’), 122.3 (C-4’), 121.6 (C-7’), 53.1 (OCH3), 52.6 (OCH3), 35.8 (SCH2), 32.6 (COCH2). EI- MS m/z [relative intensity]: 381 [M+, 10%], 323 [71%], 272 [2%], 250 [12%], 208 [41%]. Anal. Calcd. for C15H15N3 O5S2 (381.32): C, 47.23; H, 3.96; N, 11.02%. Found: C, 47.13; H, 3.85; N, 11.21%.
Crystal structure of compounds 6 [
We have corrected the wrong literature structures formed from reactions 2-(benzo[d]thiazol-2’-ylthio) acetohy-
Compound | 6 | 10 | 13 | 15 | 23 |
---|---|---|---|---|---|
Crystal Dimension/mm | 0.07 × 0.13 × 0.25 | 09 × 0.13 × 0.19 | 0.10 × 0.20 × 0.34 | 0.20 × 0.20 × 0.20 | 0.10 × 0.25 × 0.25 |
Crystal Color and Shape | Light colorless, block-like | Lightcolorless, block-like | Lightcolorless, block-like | Colorless, Prism | Colorless, block like |
Formula weight | C14H15N3O2S2 | C13H13N3O2S2 | C19H15N3O4S2 | C15H17N3O3S2 | C15H15N3O5S2 |
Crystal system | Triclinic | Monoclinic | Triclinic | Triclinic | Triclinic |
Space group | P-1 | P 121/c 1 | P-1 | P-1 | P-1 |
T/K | 296 | 296 | 296 | 296 | 296 |
a/Å | 7.8168 (5) | 12.5590 (7) | 7.5866 (6) | 7.646 (2) | 7.7601 (5) |
b//Å | 8.6997 (6) | 29.3421 (17) | 11.5021 (9) | 10.020 (2) | 10.5935 (6) |
c/Å | 11.6038 (7) | 7.9023 (5) | 11.7568 (9) | 11.640 (2) | 12.6829 (9) |
a/deg | 88.409 (3) | 90 | 99.111 (2) | 72.136 (5) | 65.372 (5) |
b/deg | 73.837 (3) | 93.870 (3) | 106.564 (3) | 77.211 (6) | 72.296 (5) |
g/deg | 82.013 (3) | 90 | 102.689 (3) | 78.761 (6) | 78.930 (6) |
V/Å3 | 750.51 (8) | 2905.4 (3) | 932.16 (13) | 820.0 (2) | 900.3 (1) |
Z | 2 | 8 | 2 | 2 | 2 |
m/mm−1 | 3.287 | 3.371 | 2.874 | 3.421 | 3.240 |
rcalcd/g・cm−3 | 1.422 | 1.405 | 1.473 | 1.423 | 1.403 |
Thetamax/deg | 61.15 | 66.66 | 66.28 | 25.00 | 26.35 |
Reflections collected | 3851 | 14154 | 11244 | 6464 | 8085 |
Unique reflections | 2218 | 4962 | 3177 | 2870 | 3645 |
Rint | 0.0170 | 0.0276 | 0.0353 | 0.0481 | 0.0244 |
R (I > 2s) | 0.0346 | 0.0425 | 0.0357 | 0.0664 | 0.0679 |
R (all data) | 0.0355 | 0.0501 | 0.0361 | 0.1071 | 0.0972 |
Rw (all data) | 0.1005 | 0.1392 | 0.0937 | 0.2302 | 0.2426 |
Peak max/e Å−3 | 0.234 | 0.391 | 0.250 | 0.45 | 0.93 |
drazide (3) with acetyl acetone and phthalic anhydride. We have also reported that both compounds 3 and 5 were utilized as a key intermediate for the synthesis of a novel heterocyclic compounds. We also reported the synthesis of a novel series of condensation and substituted derivatives of 2-(benzo[d]thiazol-2’-ylthio) acetohydrazide in good yield. The structures of the newly synthesized compounds were confirmed by elemental analysis, 1H-NMR, 13C-NMR spectra, Ms, and X-ray crystallographic investigations.
This work financed by the University of Kuwait research grant SC10/13. We are grateful to the Faculty of Science, Chemistry Department, and the SAF facility for the spectral and analytical data (Project GS01/10, GS03/08, GS01/03, GS 01/05). The CCDC file numbers for all crystal data are given in the reference section.
F.A. is the Principal Investigator, designed the research work, collected the analysis of the spectroscopic data and wrote the manuscript. A.A. is the research associate performed the work in the laboratory. All authors have read and approved the final manuscript.
The authors declare, they have no conflict of interests regarding the publication.
Fatima Al-Omran,Adel Abou El-Khair, (2016) Synthesis, Spectroscopy and X-Ray Characterization, of Novel Derivatives of Substituted 2-(Benzothiazol-2’-ylthio)acetohydrazide. International Journal of Organic Chemistry,06,31-43. doi: 10.4236/ijoc.2016.61004