Acta Chini. Slov. 2001, 48, 431-437. 431 SYNTHETIC APPROACHES TO 6-ARYL-4-[(2-FURYL)METHYLIDENE]-l-(TOSYLAMINOCARBONYL)-l,2,3,4-TETRAHYDROPYRIDAZINE-3-ONES AND5-[l-AROYLMETHYL-2-(2-FURYL)-l-ETHENYL]-2-(TOSYLAMINO)- 1,3,4-OXADIAZOLES Abdel-Sattar S. Hamad* and Ahmed I. Hashem Department of Chemistry, Faculty of Science, University of Ain Shams, Abbassia 11566, Cairo, Egypt. Tel/Fax; (00) 202-4831836 e-mail; hamad@asunet.shams.eun.eg Received 22-02-2001 Abstract Novel of 6-aryl-4-[(2-furyl)methylidene]4^tosylaminocarbonyl)-l,2,3,4-tetrahydropyridazine-3- ones 4a-d were prepared by the reaction of a-aracyl-ß-(2-furyl)acrylic acid hydrazides 2a-d with tosylisocyanate. This has been shown to occur by initial formation of#J-[2-aroylmethyl-3- (2-furyl)acroyloyl]-#2-(tosylaminocarbonyl)hydrazines 3a-d followed by acid catalyzed cyclization to afford 5-[l-aroylmethyl-2-(2-furyl)-l-ethenyl]-2-(tosylamino)-l,3,4-oxadiazoles 5a-d. Key words; furanones, pyridazinones, 1,3,4-oxadiazoles, tosylisocyanate. Introduction In connection with our synthetic approach to the 5-aryl-3-[(-2-furyl)methylidene]- 2(3//)-furanones la-d, " these compounds were isolated in almost quantitative yield upon condensation reaction of furan-2-carboxaldehyde with 3-aroylpropionic acids under Perkin conditions. Furanones la-d react with hydrazine hydrate in ethanol to give D-aracyl-E-(2-furyl)acrylic acid hydrazides 2a-b, which were found to be useful precursors in the synthesis of several heterocyclic compounds. The conversion of the 2(3//)-furanones la-d into the corresponding pyridazones 4a-d and oxadiazoles 5a-d is of potential biological interest. " Usually, 3(2//)-pyridazinones are prepared from E-oxoalkanoic acid derivatives and hydrazines and 1,3,4-oxadiazoles are prepared from 1,2-diacylhydrazines. We report here the preparation of N -[-2-aroylmethyl-3-(2-furyl)acroyloyl]-Af -(tosylaminocarbonyl)hydrazines 3a-d, which, upon acid catalyzed cyclization, furnished 6-aryl-4-[(2-furyl)methylidene]-1 -(tosylaminocarbonyl)-1,2,3,4-tetrahydropyridazine-3-ones 4a-d and 5-[l-aroylmethyl-2-(2-furyl)-l-ethenyl]-2-(tosylamino)-1,3,4-oxadiazoles 5a-d. A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylidene]... 432 Acta Chini. Slov. 2001, 48, 431-437. Results and Discussion Reaction of D-aracyl-E-(2-furyl)acrylic acid hydrazides 2a-d with tosylisocyanate at 0-25 °C gave N -[-2-aroylmethyl-3-(2-furyl)acroyloyl]-Af -(tosylaminocarbonyl) hydrazines 3a-d, and 6-aryl-4-[(2-furyl)methylidene]-l-(tosylaminocarbonyl)-l,2,3,4-tetrahydropyridazine-3-ones 4a-d. Formation of products 3a-d and 4a-d was dependent on the reaction conditions. When the reaction was carried out at 0-5 °C for 12 h, TV -[-2-aroylmethyl-3-(2-furyl)acroyloyl]-Af -(tosylaminocarbonyl)hydrazines 3a-d were obtained in 31-45% yield. However, treatment of 2a-d with tosylisocyanate at 25 °C for 48 h gave 6-aryl-4-[(2-furyl)methylidene]-l-(tosylaminocarbonyl)-l,2,3,4-tetrahydro-pyridazine-3-ones 4a-d in 75-82% yield. Pyridazinones 4a-d were also obtained by cyclization of hydrazides 3a-d in a mixture of acetonitrile and 1 N hydrochloric acid. Treatment of hyrazides 3a-d with POCI3 under reflux furnished the corresponding 5-[l-aroylmethyl-2-(2-furyl)-l-ethenyl]-2-(tosylamino)-l,3,4-oxadiazoles 5a-d in 75-81% yield (Scheme 1). Scheme 1 H H2COAr ^ IV Ar = fi a - CßH5, b — CQH4CH3, c = C6H4OCH3, d = C6H4CI CH2COAr NHNH2 CH2COAr * H : XXh3 T HO r J Ö Reagents and conditions; i) NH2NH2 . H20/ethanol, stirring at RT for 2 days; ii) Stirring with tosylisocyanate in acetonitrile at 0-5 °C for 12hrs; iii) Stirring with tosylisocyanate in acetonitrile at 25 °C for 2 days, iv) Refluxing with POCI3 for 20 min; v) Stirring with 1.0 N HCl in acetonitrile for 1h. A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylidene]... Acta Chini. Slov. 2001, 48, 431-437. 433 The structures of novel compounds 3-5 were determined by spectroscopic methods and analyses for C, H, N and S. The IR spectral data for compounds 4b,d are in agreement with the data of related l-benzoyl-6-aryl-4-thienylidene-l,6-dihydropyridazin-3-(2//)ones. Experimental !H NMR spectra were recorded on Varian Plus 300 (300 MHz) or Bruker XL 300 (300 MHz) instruments, the 13C NMR spectra (with DEPT 135) on a Bruker WP80 or XL 300 instrument. Infrared Red spectra were taken on a Perkin Elmer 1600 FT-IR spectrometer. Mass points were recorded on a Kratos Concept instrument. Melting points were measured on an Electrothermal digital melting point apparatus and are uncorrected. The Rf values reported for TLC analyses were determined on Macherey-Nagel 0.25 mm layer fluorescent UV254 plates with the indicated solvent system. Elemental analyses were performed by M-H-W Laboratories (Phoenix, AZ) at University of Minho, Braga, Portugal. 7V/-[-2-Aroylmethyl-3-(2-furyl)acroyloyl]-jV2-(tosylaminocarbonyl)hydrazines 3a-d. General Procedure A. To a suspension of D-aracyl-E-(2-furyl)acrylic acid hydrazide 2a-b (2 mmole) in CH3CN (2 mL) under nitrogen atmosphere at 0-5°, p-toluenesulfonylisocyanate (0.3 mL, 2.1 mmole) was added and the mixture was stirred at 0-5° for 12 h. The precipitate was collected by filtration to give 3a-d. Experimental and analytical data for compounds 3a-d are given in Tables 1 and 2. 6-Aryl-4-[2-furyl)methylidene]-l-(tosylaminocarbonyl)-l,2,3,4-tetrahydro-pyridazine-3-ones 4a-d. General Procedure B. To a suspension of D-aracyl-E-(2-furyl)acrylic acid hydrazide 2a-b (2 mmole) in CH3CN (2 mL) under nitrogen atmosphere at 0-5°, p-toluenesulfonylisocyanate (0.3 mL, 2.1 mmole) was added and the mixture was stirred at 0-5° for 12 hours and then at 25°for 48 h. The solvent was evaporated in vacuo and the solid residue was crystallized from ethanol to give 4a-d. General Procedure C. To a suspension of N -[2-aroylmethyl-3-(2-furyl)acroyloyl]-N -(tosylaminocarbonyl)hydrazine 3a-d (1 mmole) in acetonitrile (4 mL), 1.0 N HCl (1 A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylidene]... 434 Acta Chini. Slov. 2001, 48, 431-437. mL) was added and the mixture was stirred at 25° for one hour. The solvent was evaporated in vacuo and the solid residue was crystallized from ethanol to give 4a-d. Experimental and analytical data for compounds 4a-d are given in Tables 1,2. 5-[l-Aroylmethyl-2-(2-furyl)-l-ethenyl]-2-(tosylamino)-l,3,4-oxadiazoles 5a-d. General Procedure D. A mixture of V-[2-aroylmethyl-3-(2-furyl)acroyloyl]-Af2-(tosylaminocarbonyl)hydrazine 3a-d (2 mmole) and POCI3 (10 mL) was heated at 106 °C for 1 h. The mixture was cooled, poured into crushed ice (20 mL), neutralized with 1.0 N aqueous solution of NaHC03. The yellowish precipitate was collected by filtration, washed with water and crystallized from acetonitrile to give 5a-d. Experimental and analytical data for compounds 5a-d are given in Tables 1,2. Table 1. Physical data, yields and elemental analysis data for compounds 3-5. Cpd No. Aryl group 0„ m.p C Yield Recryst. Solv. MF Analysis [Calc./found] C H N S 3a 3b 3c 3d C6Hs C6H5CH3 CeHsOCH, CeHsCl 110-112 133-135 125-127 190-192 45% 32% 31% 34% CH3CN C23H21N306S C24H23N306S C24H23N3O7S C23H20ClN3O6S 59.09/59.55 4.52/4.62 8.98/9.78 6.85/6.73 59.98/59.86 4.82/4.85 8.74/8.74 6.67/6.68 58.05/58.01 4.66/6.65 8.46/8.57 6.45/6.77 55.03/55.15 4.01/3.99 8.37/8.36 6.38/6.42 4a 4b 4c 4d C6Hs C6H5CH3 CeHsOCH, CeHsCl 156-158 175-177 168-170 185-186 75% 82% 82% 77% EtOH C23H19N305S C24H2lN305S C24H2iN306S C23Hi8ClN305S 61.45/61.55 4.26/4.16 9.34/9.28 7.13/7.33 62.19/62.18 4.56/4.55 9.06/9.09 6.91/6.89 60.11/60.15 4.41/4.45 8.76/8.76 6.68/6.77 57.08/57.05 3.74/3.73 8.68/8.66 6.62/6.62 5a 5b 5c 5d C6Hs C6H5CH3 CeHsOCH, CeH.sCl 145-147 176-177 178-180 166-168 75% 80% 81% 75% CH3CN C23H19N305S C24H2lN305S C24H2iN306S C23Hi8ClN305S 61.45/61.55 4.26/4.16 9.34/9.28 7.13/7.33 62.19/62.18 4.56/4.55 9.06/9.09 6.91/6.89 60.11/60.15 4.41/4.45 8.76/8.76 6.68/6.77 57.08/57.05 3.74/3.73 8.68/8.66 6.62/6.62 A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylidene]... Acta Chini. Slov. 2001, 48, 431-437. 435 Table 2. Infrared (IR) and *H NMR (300 MHz) spectral data for compounds 3-5. Cpd. No Aryl group (IR) „,„,. (Nuìolì/ cm VC=0; vc=N; V-NH 'HNMR (300 MHz, DMSO-d6); ÔH [DMSO-d6] 3a C6H5 1667(s), 1725(w), 3112(w), 3263.6(s) 5= 2.36 (s, 3H, Ar-CH3), 3.85 (s, 2H, CffiCOPh), 6.63 (dd, IH, /=1.8, 3.3 Hz, Furan-H4), 6.75 (d, IH, J= 3 Hz, Furan-H3), 7.04 (s, IH, furan-CH=C-), 7.35 (d, 2H, J = 8.4 Hz, Ar-H), 7.37-7.43 (m, 5H, Ph-H), 7.64 (d, J= 1.8 Hz, Furan-H5), 7.75 (d, 2H, J= 8.1 Hz, Ar-H), 9.30 (s, IH, -NH-NH-), 10.67 (s, 1H,-NH-NH-), 11.63 (s, IH, -CONHS02-Ar) ppm. 3b CgH5CH3 1667(s), 1699, 1725.8(w), 3099(w), 3266.6(S) 5= 2.36 (s, 3H, Ar-CH3), 2.37 (s, 3H, Ar-CH3), 3.88 (s, 2H, CffiCOAr), 6.70 (s, IH, furan-CH=C-), 6.87 (d, 2H, J = 9 Hz, Ar-H), 7.00 (d, IH, J = 3.6 Hz, Furan-H3), 7.14 (dd, IH, J = 1.8, 3.6 Hz, Furan-H4), 7.32 (d, 2H, J= 8.1 Hz, Ar-H), 7.45 (d, 2R,J=9 Hz, Ar-H), 7.69 (d, 2H, J = 7.5 Hz, Ar-H), 7.82 (s, IH, -NH-NH-), 7.96 (d,J= 1.5 Hz, Furan-H5), 8.28 (s, IH, -NH-NH-), 10.68 (s, IH, -CONHS02-Ar) ppm. 3c C6H5OCH3 1651(s), 1680(s), 1737(w), 3214(s), 3376(w) 5 = 2.44 (s, 3H, Ar-CHj), 3.80 (s, 3H, Ar-OCHj), 3.85 (s, 2H, CffiCOAr), 6.75 (d, IH, J = 3 Hz, furan-CH=C-), 6.85 (d, 2H, J= 9 Hz, Ar-H), 7.05 (d, IH, J = 3.6 Hz, Furan-H3), 7.12 (dd, IH, J = 1.8, 3.6 Hz, Furan-H4), 7.37 (d, 2H, J = 8.1 Hz, Ar-H), 7.41 (d, 2H, J= 9 Hz, Ar-H), 7.71 (d, 2H, J= 7.5 Hz, Ar-H), 7.81 (s, IH, -NH-NH-), 7.95 (d,J= 1.5 Hz, Furan-H5), 8.27 (s, IH, -NH-NH-), 10.68 (s, IH, -CONHS02-Ar) ppm. 3d C6H5C1 1663(s), 1702(s), 1726.l(w), 3233(s), 3316(w) 5= 2.38 (s, 3H, Ar-CHj), 3.79 (s, 2H, CH2COAr), 6.61 (s, IH, furan-CH=C-), 6.85 (d, 2R,J=9 Hz, Ar-H), 7.1 (d, IH, J= 3.6 Hz, Furan-H3), 7.2 (dd, 1H,J = 1.8, 3.6 Hz, Furan-H4), 7.38 (d, 2R,J= 8.1 Hz, Ar-H), 7.42 (d, 2R,J=9 Hz, Ar-H), 7.73 (d, 2H, J= 7.5 Hz, Ar-H), 7.85 (s, IH, -NH-NH-), 7.97 (d, J = 1.5 Hz, Furan-H5), 8.57 (s, IH, -NH-NH-), 10.72 (s, IH, -CONHS02-Ar) ppm. 4a C6H5 1662(s),1699(w)3112(w), 3263.6(s) 5 = 2.38 (s, 3H, Ar-CH,), 6.55 (s, IH, -CH=C-Ar), 6.70 (dd, YK,J= 1.8, 3.3 Hz, Furan-H4), 7.06 (s, IH, furan-CH=C-), 7.15 (d, IH, J = 3.3 Hz, Furan-H3), 7.30-7.42 (m, 5H, Ph-H), 7.46 (d, 2H, J= 8.4 Hz, Ar-H), 7.69 (d, 2H, J= 8.1 Hz, Ar-H), 7.95 (d,J= 1.5 Hz, Furan-H5), 9.32 (s, IH, NH), 11.49 (s, IH, -CONHS02-Ar) ppm. 4b C6H5CH3 1668(s), 1725.8(w), 3099(w), 3266.6(S) 5 = 2.35 (s, 3H, Ar-CHj), 2.38 (s, 3H, Ar-CHj), 6.48 (s, IH, -CH=C-Ar), 6.71 (dd, IH, J = 1.8, 3.6 Hz, Furan-H4), 6.85 (d, 2H, J= 8.7 Hz, Ar-H), 6.98 (s, IH, furan-CH=C-), 7.18 (d, IH, J = 3.6 Hz, furan-H3), 7.36 (d, 2H, J= 8.4, Ar-H), 7.42 (d, 2H, J= 8.7 Hz, Ar-H), 7.68 (d, 2H, J = 8.4 Hz, Ar-H), 7.92 (d, J = 1.5 Hz, furan-H5), 8.32 (s, IH, NH), 10.49 (s, IH, -CONHS02-Ar) ppm. A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylidene]... 436 Acta Chini. Slov. 2001, 48, 431-437. Table 2 Continued. 4c C6H5OCH3 1679(s), 1737(w), 3214(s), 3376(w) 5 = 2.36 (s, 3H, Ar-Cä), 3.78 (s, 3H, Ar-OCHj), 6.46 (s, IH, -CH=C-Ar), 6.68 (dd, IH, J = 1.8, 3.3 Hz, Furan-H4), 6.86 (d, 2H, J= 8.7 Hz, Ar-H), 6.99 (s, IH, furan-CH=C-), 7.1 (d, YR,J= 3.3 Hz, furan-H3), 7.35 (d, 2H, J = 8.4 Hz, Ar-H), 7.42 (d, 2H, J = 9 Hz, Ar-H), 7.69 (d, 2H, J= 8.4 Hz, Ar-H), 7.92 (d, J= 1.5 Hz, furan-H5), 8.27 (s, IH, NH), 10.67 (s, IH, -CONHS02-Ar) ppm. 4d C6H5C1 1665(s), 1728(w), 3233(s), 3316(w) 5 = 2.38 (s, 3H, Ar-CH,), 6.54 (s, IH, -CH=C-Ar), 6.71 (dd, IH, /=1.8, 3.3 Hz, Furan-H4), 6.87 (d, 2H, J= 8.4 Hz, Ar-H), 7.1 (s, IH, furan-CH=C-), 7.18 (d, IH, J= 3.3 Hz, furan-H3), 7.37 (d, 2H, J= 8.7 Hz, Ar-H), 7.47 (d, 2R,J= 8.4 Hz, Ar-H), 7.69 (d, 2H, J= 8.1 Hz, Ar-H), 7.95 (d,J= 1.5 Hz, furan-H5), 9.34 (s, IH, NH), 10.86 (s, IH, -CONHS02-Ar) ppm. 5a CgH5 1698.2(s), 1578-1615, 3263 5 = 2.38 (s, 3H, Ar-CHj), 4.36 (s, 2H, -CffiCOPh), 6.66 (dd, IH, J= 1.8, 3.3 Hz, Furan-H4), 7.1 (s, IH, furan-CH=C-), 7.15 (d, IH, J = 3.3 Hz, Furan-H3), 7.35-7.46 (m, 5H, Ph-H), 7.48 (d, 2H, J= 8.4 Hz, Ar-H), 7.69 (d, 2H, J= 8.4 Hz, Ar-H), 7.95 (d, J= 1.5 Hz, Furan-H5), 11.49 (s, IH, -CONHS02-Ar) ppm. 5b C6H5CH3 1692(s), 1587-1613, 3216(s) 5 = 2.35 (s, 3H, Ar-CHj), 2.38 (s, 3H, Ar-CHj), 4.36 (s, 2H, -CH2COAr), 6.67 (dd, IH, J = 1.8, 3.6 Hz, Furan-H4), 6.82 (d, 2H, J= 8.4 Hz, Ar-H), 6.98 (s, IH, furan-CH=C-), 7.17 (d, IH, J = 3.3 Hz, furan-H3), 7.35 (d, 2H, J= 8.7, Ar-H), 7.44 (d, 2H, J= 8.4 Hz, Ar-H), 7.67 (d, 2H, J= 8.7 Hz, Ar-H), 7.93 (d,J= 1.5 Hz, furan-H5), 10.49 (s, IH, -CONHS02-Ar) ppm. 5c C6H5OCH3 1692(s), 1589-1610, 3220(s) 5 = 2.38 (s, 3H, Ar-CH,), 3.81 (s, 3H, Ar-OCH,), 4.47 (s, 2H, -CH2COAr)„ 6.71 (dd, 1H,J= 1.8, 3.3 Hz, Furan-H4), 6.87 (d, 2H, J= 8.4 Hz, Ar-H), 7.1 (s, IH, furan-CH=C-), 7.18 (d, 1H,J= 3.3 Hz, Furan-H3), 7.37 (d, 2H, J= 8.7 Hz, Ar-H), 7.47 (d, 2H, J= 8.4 Hz, Ar-H), 7.69 (d, 2H, J= 8.7 Hz, Ar-H), 7.95 (d,J = 1.5 Hz, Furan-H5), 10.86 (s, IH, -CONHS02-Ar) ppm. 5d C6H5C1 1689(s), 1590-1620, 3217(s) 5= 2.38 (s, 3H, Ar-CH,), 4.47 (s, 2H, -CHzCOAr),, 6.71 (dd, IH, J= 1.8, 3.3 Hz, Furan-H4), 6.87 (d, 2H, J= 8.4 Hz, Ar-H), 7.1 (s, IH, furan-CH=C-), 7.18 (d, IH, J= 3.3 Hz, Furan-H3), 7.37 (d, 2H, J= 8.7 Hz, Ar-H), 7.47 (d, 2H, J= 8.4 Hz, Ar-H), 7.69 (d, 2H, J = 8.7 Hz, Ar-H), 7.95 (d, J= 1.5 Hz, Furan-H5), 10.86 (s, IH, -CONHS02-Ar) ppm. Conclusion 6-Aryl-4-[(2-furyl)methylidene]-l-(tosylaminocarbonyl)-l,2,3,4-tetrahydropyridazin-3- ones 4a-d and 5-[l-aroylmethyl-2-(2-furyl)-l-ethenyl]-2-(tosylamino)-l,3,4-oxadiazoles 5a-d were prepared in one step by acid catalyzed cyclization of N -[2-aroylmethyl-3-(2-furyl)acroyloyl]-A^ -(tosylaminocarbonyl)hydrazines 3a-d in good yields. A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylidene]... Acta Chini. Slov. 2001, 48, 431-437. 437 Acknowledgment The authors thank gratefully, Department of Chemistry, University of Minho, 4710 Braga, Portugal for facilities of obtained spectral data. References 1. Hashem, A. and Senning, A. "Advances in Heterocylic Chemistry' 1999, 73, 275-93. 2. Hashem, A. I., Senning, A. and Hamad, A-S. S. Org. Prep. Proced. int. 1998, 30 (4), 403-425. 3. Hamad, A-S. S.; Hashem, A. I. El-Kafrawy, A. F.; Saad, M. M. Phosphorus, Sulfur and Silicon 2000, 159, 157-169. 4. El-Kafrawy, A. F.; Youssef, A. S. A.; Hamad, A-S. S.; Hashem, A. I. 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Yassin, S.; Abd El-Aleem H. A-El-A.; El-Sayed I. E.; Hashem A. I, Collect. Czech Chem. Commun. 1993, 58, 1925-1930. Povzetek Nove derivate 6-aril-4-[(2-furil)metiliden]-1 -(tozilaminokarbonil)-1,2,3,4-tetrahidro-piridazin-3-onov 4a-d smo pripravili z reakcijami a-aracil-ß-(2-furil)akrilohidrazidov 2a-d s tozilisocianatom in jih nato pretvorili v 5-[l-aroilmetil-2-(2-furil)-l-etenil]-2-(tozilamino)-1,3,4-oksadiazole 5a-d. Strukture spojin in intermediatov smo potrdili z analiznimi in spektroskopskimi podatki. A.-S. S. Hamad, A. I. Hashem: Synthetic approaches to 4-[(2-furyl)methylìdene]...