In analogy with hCA IX, the methoxy organizations in the scaffold did not influence significantly the potency of inhibition. Conclusions In summary, a series of curcumin inspired sulfonamide derivatives (5aCj) were synthesized from chalcones and 4-sulfamoyl benzaldehyde by using ClaisenCSchmidt condensation. 5d, was found to be almost 9 times more selective against hCA II (KI =?0.89?nM) over hCA IX and hCA XII, whereas 5e was 3 and 70 occasions more selective against hCA II (KI =?0.75?nM) over hCA IX and hCA XII, respectively. values were given in Hertz. The following abbreviations were utilized for 1H NMR spectra to indicate the signal multiplicity: s (singlet), d (doublet), dd (doublet of doublet), and m (multiplet). HRMS were decided with Agilent QTOF mass spectrometer 6540 series instrument using ESI technique. General procedure for the synthesis of 3aCj To a stirred answer of appropriately substituted benzaldehydes 1aCj (1?mmol) in ethanol (3?ml) was added 0.5?ml of acetone (2) and 15% aqueous NaOH (1?ml) answer at 0?C. The reaction was allowed to stir at room heat till it was completed. The reaction combination was evaporated to dryness, extracted twice with ethyl acetate, and the combined organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by column chromatography (Silica gel, 60C120 mesh, 9:1 hexane/ethyl acetate) to obtain the desired chalcones 3aCj in good to very good yields. General procedure for the synthesis of 5aCj To a stirred answer of chalcone 3aCj (0.5?mmol) in ethanol (3?ml) was added 15% aqueous NaOH (1?ml) answer and aldehyde 4 (0.5?mmol) at 0?C. The producing answer was stirred at room temperature till the complete consumption of starting materials was observed. The reaction combination was evaporated to dryness, extracted twice with ethyl acetate, and the combined Eluxadoline organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude mass was purified by recrystallization in ethanol or ethyl acetate to give the pure product 5aCj in yields of 35C45%. 4-((1E,4E)-5-(4-isopropoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5a) Yellow solid, yield 42%; mp: 163C165?C; IR (KBr, cm?1): 7.98 (d, 189.1, 156.3, 144.2, 143.8, 138.5, 131.0, 130.0, 129.2, 126.6, 125.9, 125.2, 123.7, 116.3, 69.9, 22.3, 22.2; HRMS (ESI): Calcd for C20H22NO4S 372.1264, found 372.1262 [M?+?H]+. 4-((1E,4E)-5-(4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5b) Yellow solid, yield 39%; mp: 192C193?C; IR (KBr, cm?1): 7.98 (d, 188.7, 161.8, 145.5, 143.8, 140.8, 138.5, 130.9, 129.3, 128.2, 127.6, 126.6, 123.9, 115.0, 55.8; HRMS (ESI): Calcd for C18H18NO4S 344.0951, found 344.0950 [M?+?H]+. 4-((1E,4E)-5-(2,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5c) Yellow solid, yield 40%; mp: 185C186?C; IR (KBr, cm?1): 7.97 (d, 188.7, 163.6, 160.5, 145.5, 140.5, 138.6, 138.5, 130.8, 129.2, 129.0, 126.6, 123.5, 116.3, 106.9, 98.9, 56.3, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1061 [M?+?H]+. 4-((1E,4E)-5-(2,5-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5d) Yellow solid, yield 38%; mp: 202C203?C; IR (KBr, cm?1): 7.98 (d, 188.7, 153.7, 153.2, 144.3, 143.3, 141.3, 138.0, 129.3, 126.6, 123.5, 118.5, 113.6, 113.5, 113.2, 56.5, 56.1; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1060 [M?+?H]+. 4-((1E,4E)-5-(3,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5e) Yellow solid, yield 40%; mp: 198C200?C; IR (KBr, cm?1): 7.99 (d, 188.7, 151.7, 149.5, 145.5, 144.3, 140.7, 138.5, 130.5, 129.2, 128.1, 127.8, 126.8, 126.6, 124.2, 123.9, 112.1, 111.0, 56.5, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1055 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,3,4-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5f) Yellow solid, yield 35%; mp: 159C161?C; IR (KBr, cm?1): 7.98 (d, 188.7, 156.2, 153.5, 145.5, 142.3, 140.9, 138.4, 138.1, 129.3, 129.0, 126.6, 124.5, 123.9, 121.3, 109.0, 61.9, 60.9, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1169 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,4,6-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5g) Yellow solid, yield 43%; mp: 249C251?C; IR (KBr, cm?1): 8.07C8.01 (m, 1H), 7.97 (d, 189.4, 161.8, 160.4, 145.1, 141.1, 137.3, 130.9, 129.2, 128.8, 126.6, 123.6, 115.9, 104.8, 90.1, 55.3, 54.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1166 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(3,4,5-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5h) Yellow solid, yield 45%; mp: 242C244?C; IR (KBr, cm?1): 8.11C7.99 (m, 2H), 7.97 (d, 188.6, 153.2, 143.3, 142.7, 138.6, 130.5, 129.3, 127.8, 126.8, 123.7, 119.1, 104.1, 60.6, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1164 [M?+?H]+. 4-((1E,4E)-5-(4-chlorophenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5i) Yellow solid, yield 43%; mp: 205C206?C; IR (KBr, cm?1): 7.99 (d, 188.9, 145.6, 142.3, 142.0, 141.6, 138.3, 135.6, 135.5, 134.1, 130.7, 129.5, 129.3, 128.1, 126.7, 126.6; HRMS (ESI): Calcd for C17H15ClNO3S 348.0456, found 348.0448 [M?+?H]+. 4-((1E,4E)-5-(2-fluoro-4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5j) Yellow solid, yield 40%; mp: 167C169?C; IR (KBr, cm?1): 7.99 (d, 188.7, 161.7, 158.6, 145.6, 143.3, 141.5, 138.5, 130.8, 128.3, 126.6,.Interesting inhibitory activities were observed against almost all these isoforms as follows. the new sulfonamides, with KIs in the range of 2.3C87.3?nM, whereas hCA XII, and antiglaucoma and anticancer drug target, was inhibited with KIs in the range of 6.1C71.8?nM. It is noteworthy that one of the new compounds, 5d, was found to be almost 9 times more selective against hCA II (KI =?0.89?nM) over hCA IX and hCA XII, whereas 5e was 3 and 70 occasions more selective against hCA II (KI =?0.75?nM) over hCA IX and hCA XII, respectively. values were given in Hertz. The following abbreviations were utilized for 1H NMR spectra to indicate the signal multiplicity: s (singlet), d (doublet), dd (doublet of doublet), and m (multiplet). HRMS were decided with Agilent QTOF mass spectrometer 6540 series instrument using ESI technique. General procedure for the synthesis of 3aCj To a stirred answer of appropriately substituted benzaldehydes 1aCj (1?mmol) in ethanol (3?ml) was added 0.5?ml of acetone (2) and 15% aqueous NaOH (1?ml) answer at 0?C. The reaction was allowed to stir at room heat till it was completed. The reaction combination was evaporated to dryness, extracted twice with ethyl acetate, and the combined organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by column chromatography (Silica gel, 60C120 mesh, 9:1 hexane/ethyl acetate) to obtain the desired chalcones 3aCj in good to very good yields. General procedure for the synthesis of 5aCj To a stirred answer of chalcone 3aCj (0.5?mmol) in ethanol (3?ml) was added 15% aqueous NaOH (1?ml) answer and aldehyde 4 (0.5?mmol) at 0?C. The producing answer was stirred at room temperature till the complete consumption of starting materials was observed. The reaction combination was evaporated to dryness, extracted twice with ethyl acetate, and the combined organic layers were dried over anhydrous Na2SO4 and concentrated under decreased pressure. The crude mass was purified by recrystallization in ethanol or ethyl acetate to provide the pure item 5aCj in produces of 35C45%. 4-((1E,4E)-5-(4-isopropoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5a) Yellowish solid, produce 42%; mp: 163C165?C; IR (KBr, cm?1): 7.98 (d, 189.1, 156.3, 144.2, 143.8, 138.5, 131.0, 130.0, 129.2, 126.6, 125.9, 125.2, 123.7, 116.3, 69.9, 22.3, 22.2; HRMS (ESI): Calcd for C20H22NO4S 372.1264, found 372.1262 [M?+?H]+. 4-((1E,4E)-5-(4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5b) Yellowish solid, produce 39%; mp: 192C193?C; IR (KBr, cm?1): 7.98 (d, 188.7, 161.8, 145.5, 143.8, 140.8, 138.5, 130.9, 129.3, 128.2, 127.6, 126.6, 123.9, 115.0, 55.8; HRMS (ESI): Calcd for C18H18NO4S 344.0951, found 344.0950 [M?+?H]+. 4-((1E,4E)-5-(2,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5c) Yellowish solid, produce 40%; mp: 185C186?C; IR (KBr, cm?1): 7.97 (d, 188.7, 163.6, 160.5, 145.5, 140.5, 138.6, 138.5, 130.8, 129.2, 129.0, 126.6, 123.5, 116.3, 106.9, 98.9, 56.3, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1061 [M?+?H]+. 4-((1E,4E)-5-(2,5-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5d) Yellowish solid, produce 38%; mp: 202C203?C; IR (KBr, cm?1): 7.98 (d, 188.7, 153.7, 153.2, 144.3, 143.3, 141.3, 138.0, 129.3, 126.6, 123.5, 118.5, 113.6, 113.5, 113.2, 56.5, 56.1; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1060 Eluxadoline [M?+?H]+. 4-((1E,4E)-5-(3,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5e) Yellowish solid, produce 40%; mp: 198C200?C; IR (KBr, cm?1): 7.99 (d, 188.7, 151.7, 149.5, 145.5, 144.3, 140.7, 138.5, 130.5, 129.2, 128.1, 127.8, 126.8, 126.6, 124.2, 123.9, 112.1, 111.0, 56.5, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1055 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,3,4-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5f) Yellowish solid, produce 35%; mp: 159C161?C; IR (KBr, cm?1): 7.98 (d, 188.7, 156.2, 153.5, 145.5, 142.3, 140.9, 138.4, 138.1, 129.3, 129.0, 126.6, 124.5, 123.9, 121.3, 109.0, 61.9, 60.9, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1169 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,4,6-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5g) Yellowish solid, produce 43%; mp: 249C251?C; IR (KBr, cm?1): 8.07C8.01 (m, 1H), 7.97 (d, 189.4, 161.8, 160.4, 145.1, 141.1, 137.3, 130.9, 129.2, 128.8, 126.6, 123.6, 115.9, 104.8, 90.1, 55.3, 54.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1166 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(3,4,5-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5h) Yellowish solid, produce 45%; mp: 242C244?C; IR (KBr, cm?1): 8.11C7.99 (m, 2H), 7.97 (d, 188.6, 153.2, 143.3, 142.7, 138.6, 130.5, 129.3, 127.8, 126.8, 123.7, 119.1, 104.1, 60.6, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1164 [M?+?H]+. 4-((1E,4E)-5-(4-chlorophenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5i) Yellowish solid, produce 43%; mp: 205C206?C; IR (KBr, cm?1): 7.99 (d, 188.9, 145.6, 142.3, 142.0, 141.6, 138.3, 135.6, 135.5, 134.1, 130.7, 129.5,.Alternatively, substances 5hCj and 5eCf inhibited this isoform in moderate nanomolar range (KI 31.1C71.8?nM). among the fresh substances, 5d, was discovered to be nearly 9 times even more selective against hCA II (KI =?0.89?nM) more than hCA IX and hCA XII, whereas 5e was 3 and 70 moments more selective against hCA II (KI =?0.75?nM) more than hCA IX and hCA XII, respectively. ideals received in Hertz. The next abbreviations were useful for 1H NMR spectra to point the sign multiplicity: s (singlet), d (doublet), dd (doublet of doublet), and m (multiplet). HRMS had been established with Agilent QTOF mass spectrometer 6540 series device using ESI technique. General process of the formation of 3aCj To a stirred option of properly substituted benzaldehydes 1aCj (1?mmol) in ethanol (3?ml) was added 0.5?ml of acetone (2) and 15% aqueous NaOH (1?ml) option in 0?C. The response was permitted to mix at room temperatures till it had been completed. The response blend was evaporated to dryness, extracted double with ethyl acetate, as well as the mixed organic layers had been dried out over anhydrous Na2Thus4 and focused under decreased pressure. The crude item was purified by column chromatography (Silica gel, 60C120 mesh, 9:1 hexane/ethyl acetate) to get the preferred chalcones 3aCj in great to very great yields. General process of the formation of 5aCj To a stirred option of chalcone 3aCj (0.5?mmol) in ethanol (3?ml) was added 15% aqueous NaOH (1?ml) option and aldehyde 4 (0.5?mmol) in 0?C. The ensuing option was stirred at space temperature till the entire consumption of beginning materials was noticed. The reaction blend was evaporated to dryness, extracted double with ethyl acetate, as well as the mixed organic layers had been dried out over anhydrous Na2Thus4 and focused under decreased pressure. The crude mass was purified by recrystallization in ethanol or ethyl acetate to provide the pure item 5aCj in produces of 35C45%. 4-((1E,4E)-5-(4-isopropoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5a) Yellowish solid, produce 42%; mp: 163C165?C; IR (KBr, cm?1): 7.98 (d, 189.1, 156.3, 144.2, 143.8, 138.5, 131.0, 130.0, 129.2, 126.6, 125.9, 125.2, 123.7, 116.3, 69.9, 22.3, 22.2; HRMS (ESI): Calcd for C20H22NO4S 372.1264, found 372.1262 [M?+?H]+. 4-((1E,4E)-5-(4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5b) Yellowish solid, produce 39%; mp: 192C193?C; IR (KBr, cm?1): 7.98 (d, 188.7, 161.8, 145.5, 143.8, 140.8, 138.5, 130.9, 129.3, 128.2, 127.6, 126.6, 123.9, 115.0, 55.8; HRMS (ESI): Calcd for C18H18NO4S 344.0951, found 344.0950 [M?+?H]+. 4-((1E,4E)-5-(2,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5c) Yellowish solid, produce 40%; mp: 185C186?C; IR (KBr, cm?1): 7.97 (d, 188.7, 163.6, 160.5, 145.5, 140.5, 138.6, 138.5, 130.8, 129.2, 129.0, 126.6, 123.5, 116.3, 106.9, 98.9, 56.3, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1061 [M?+?H]+. 4-((1E,4E)-5-(2,5-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5d) Yellowish solid, produce 38%; mp: 202C203?C; IR (KBr, cm?1): 7.98 (d, 188.7, 153.7, 153.2, 144.3, 143.3, 141.3, 138.0, 129.3, 126.6, 123.5, 118.5, 113.6, 113.5, 113.2, 56.5, 56.1; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1060 [M?+?H]+. 4-((1E,4E)-5-(3,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5e) Yellowish solid, produce 40%; mp: 198C200?C; IR (KBr, cm?1): 7.99 (d, 188.7, 151.7, 149.5, 145.5, 144.3, 140.7, 138.5, 130.5, 129.2, 128.1, 127.8, 126.8, 126.6, 124.2, 123.9, 112.1, 111.0, 56.5, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1055 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,3,4-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5f) Yellowish solid, produce 35%; mp: 159C161?C; IR (KBr, cm?1): 7.98 (d, 188.7, 156.2, 153.5, 145.5, 142.3, 140.9, 138.4, 138.1, 129.3, 129.0, 126.6, 124.5, 123.9, 121.3, 109.0, 61.9, 60.9, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1169 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,4,6-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5g) Yellowish solid, produce 43%; mp: 249C251?C; IR (KBr, cm?1): 8.07C8.01 (m, 1H), 7.97 (d, 189.4, 161.8, 160.4, 145.1, 141.1, 137.3, 130.9, 129.2, 128.8, 126.6, 123.6, 115.9, 104.8, 90.1, 55.3, 54.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1166 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(3,4,5-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5h) Yellowish solid, produce 45%; mp: 242C244?C; IR (KBr, cm?1): 8.11C7.99 (m, 2H), 7.97 (d, 188.6, 153.2, 143.3, 142.7, 138.6, 130.5, 129.3, 127.8, 126.8, 123.7, 119.1, 104.1, 60.6, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1164 [M?+?H]+. 4-((1E,4E)-5-(4-chlorophenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5i) Yellowish solid, produce 43%; mp: 205C206?C; IR (KBr, cm?1): 7.99 (d, 188.9, 145.6, 142.3, 142.0, 141.6, 138.3, 135.6, 135.5, 134.1, 130.7, 129.5, 129.3, 128.1, 126.7, 126.6; HRMS (ESI): Calcd for C17H15ClNO3S 348.0456, found 348.0448 [M?+?H]+. 4-((1E,4E)-5-(2-fluoro-4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5j) Yellowish solid, produce 40%; mp: 167C169?C; IR (KBr, cm?1): 7.99 (d, 188.7, 161.7, 158.6, 145.6, 143.3, 141.5, 138.5, 130.8, 128.3, 126.6, 123.7, 116.8, 111.2, 106.7, 55.7; HRMS (ESI): Calcd for C18H17FNO4S 362.0857, found 362.0856 [M?+?H]+. CA inhibition assay An Applied Rabbit Polyclonal to HNRPLL Photophysics stopped-flow device has been useful for assaying the CA catalyzed CO2 hydration activity29. Phenol reddish colored (at a focus of 0.2?mM) continues to be used as sign, working in the.of India, New Delhi, for the award of a NIPER fellowship. Disclosure statement No potential conflict appealing was reported from the authors.. fresh substances, 5d, was discovered to be nearly 9 times even more selective against hCA II (KI =?0.89?nM) more than hCA IX and hCA XII, whereas 5e was 3 and 70 moments more selective against hCA II (KI =?0.75?nM) more than hCA IX and hCA XII, respectively. ideals received in Hertz. The next abbreviations were useful for 1H NMR spectra to point the sign multiplicity: s (singlet), d (doublet), dd (doublet of doublet), and m (multiplet). HRMS had been established with Agilent QTOF mass spectrometer 6540 series device using ESI technique. General process of the formation of 3aCj To a stirred option of properly substituted benzaldehydes 1aCj (1?mmol) in ethanol (3?ml) was added 0.5?ml of acetone (2) and 15% aqueous NaOH (1?ml) option in 0?C. The response was permitted to mix at room temperatures till it had been completed. The response blend was evaporated to dryness, extracted double with ethyl acetate, as well as the mixed organic layers had been dried out over anhydrous Na2Thus4 and focused under decreased pressure. The crude product was purified by column chromatography (Silica gel, 60C120 mesh, 9:1 hexane/ethyl acetate) to obtain the desired chalcones 3aCj in good to very good yields. General procedure for the synthesis of 5aCj To a stirred solution of chalcone 3aCj (0.5?mmol) in ethanol (3?ml) was added 15% aqueous NaOH (1?ml) solution and aldehyde 4 (0.5?mmol) at 0?C. The resulting solution was stirred at room temperature till the complete consumption of starting materials was observed. The reaction mixture was evaporated to dryness, extracted twice with ethyl acetate, and the combined organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude mass was purified by recrystallization in ethanol or ethyl acetate to give the pure product 5aCj in yields of 35C45%. 4-((1E,4E)-5-(4-isopropoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5a) Yellow solid, yield 42%; mp: 163C165?C; IR (KBr, cm?1): 7.98 (d, 189.1, 156.3, 144.2, 143.8, 138.5, 131.0, 130.0, 129.2, 126.6, 125.9, 125.2, 123.7, 116.3, 69.9, 22.3, 22.2; HRMS (ESI): Calcd for C20H22NO4S 372.1264, found 372.1262 [M?+?H]+. 4-((1E,4E)-5-(4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5b) Yellow solid, yield 39%; mp: 192C193?C; IR (KBr, cm?1): 7.98 (d, 188.7, 161.8, 145.5, 143.8, 140.8, 138.5, 130.9, 129.3, 128.2, 127.6, 126.6, 123.9, 115.0, 55.8; HRMS (ESI): Calcd for C18H18NO4S 344.0951, found 344.0950 [M?+?H]+. 4-((1E,4E)-5-(2,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5c) Yellow solid, yield 40%; mp: 185C186?C; IR (KBr, cm?1): 7.97 (d, 188.7, 163.6, 160.5, 145.5, 140.5, 138.6, 138.5, 130.8, 129.2, 129.0, 126.6, 123.5, 116.3, 106.9, 98.9, 56.3, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1061 [M?+?H]+. 4-((1E,4E)-5-(2,5-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5d) Yellow solid, yield 38%; mp: 202C203?C; IR (KBr, cm?1): 7.98 (d, 188.7, 153.7, 153.2, 144.3, 143.3, 141.3, 138.0, 129.3, 126.6, 123.5, 118.5, 113.6, 113.5, 113.2, 56.5, 56.1; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1060 [M?+?H]+. 4-((1E,4E)-5-(3,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5e) Yellow solid, yield 40%; mp: 198C200?C; IR (KBr, cm?1): 7.99 (d, 188.7, 151.7, 149.5, 145.5, 144.3, 140.7, 138.5, 130.5, 129.2, 128.1, 127.8, 126.8, 126.6, 124.2, 123.9, 112.1, 111.0, 56.5, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1055 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,3,4-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5f) Yellow solid, yield 35%; mp: 159C161?C; IR (KBr, cm?1): 7.98 (d, 188.7, 156.2, 153.5, 145.5, 142.3, 140.9, 138.4, 138.1, 129.3, 129.0, 126.6, 124.5, 123.9, 121.3, 109.0, 61.9, 60.9, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1169 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,4,6-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5g) Yellow solid, yield 43%; mp: 249C251?C; IR (KBr, cm?1): 8.07C8.01 (m, 1H), 7.97 (d, 189.4, 161.8, 160.4, 145.1, 141.1, 137.3, 130.9, 129.2, 128.8, 126.6, 123.6, 115.9, 104.8, 90.1, 55.3, 54.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1166 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(3,4,5-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5h) Yellow solid, yield 45%; mp: 242C244?C; IR (KBr, cm?1): 8.11C7.99 (m, 2H), 7.97 (d, 188.6, 153.2, 143.3, 142.7, 138.6, 130.5, 129.3, 127.8, 126.8, 123.7, 119.1, 104.1, 60.6, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1164 [M?+?H]+. 4-((1E,4E)-5-(4-chlorophenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5i) Yellow solid, yield 43%; mp: 205C206?C;.Interesting inhibitory activities were observed against all these isoforms. used for 1H NMR spectra to indicate the signal multiplicity: s (singlet), d (doublet), dd (doublet of doublet), and m (multiplet). HRMS were determined with Agilent QTOF mass spectrometer 6540 series instrument using ESI technique. General procedure for the synthesis of 3aCj To a stirred solution of appropriately substituted benzaldehydes 1aCj (1?mmol) in ethanol (3?ml) was added 0.5?ml of acetone (2) and 15% aqueous NaOH (1?ml) solution at 0?C. The reaction was allowed to stir at room temperature till it was completed. The reaction mixture was evaporated to dryness, extracted twice with ethyl acetate, and the combined organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by column chromatography (Silica gel, 60C120 mesh, 9:1 hexane/ethyl acetate) to obtain the desired chalcones 3aCj in good to very good yields. General procedure for the synthesis of 5aCj To a stirred solution of chalcone 3aCj (0.5?mmol) in ethanol (3?ml) was added 15% aqueous NaOH (1?ml) solution and aldehyde 4 (0.5?mmol) at 0?C. The resulting solution was stirred at room temperature till the complete consumption of starting materials was observed. The reaction mixture was evaporated to dryness, extracted twice with ethyl acetate, and the combined organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude mass was purified by recrystallization in ethanol or ethyl acetate to give the pure product 5aCj in yields of 35C45%. 4-((1E,4E)-5-(4-isopropoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5a) Yellow solid, yield 42%; mp: 163C165?C; IR (KBr, cm?1): 7.98 (d, 189.1, 156.3, 144.2, 143.8, 138.5, 131.0, 130.0, 129.2, 126.6, 125.9, 125.2, 123.7, 116.3, 69.9, 22.3, 22.2; HRMS (ESI): Calcd for C20H22NO4S 372.1264, found 372.1262 [M?+?H]+. 4-((1E,4E)-5-(4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5b) Yellow solid, yield 39%; mp: 192C193?C; IR (KBr, cm?1): 7.98 (d, 188.7, 161.8, 145.5, 143.8, 140.8, 138.5, 130.9, 129.3, 128.2, 127.6, 126.6, 123.9, 115.0, 55.8; HRMS (ESI): Calcd for C18H18NO4S 344.0951, found 344.0950 [M?+?H]+. 4-((1E,4E)-5-(2,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5c) Yellow solid, yield 40%; mp: 185C186?C; IR (KBr, cm?1): 7.97 (d, 188.7, 163.6, 160.5, 145.5, 140.5, 138.6, 138.5, 130.8, 129.2, 129.0, 126.6, 123.5, 116.3, 106.9, 98.9, 56.3, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1061 [M?+?H]+. 4-((1E,4E)-5-(2,5-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5d) Yellow solid, yield 38%; mp: 202C203?C; IR (KBr, cm?1): 7.98 (d, 188.7, 153.7, 153.2, 144.3, 143.3, 141.3, 138.0, 129.3, 126.6, 123.5, 118.5, 113.6, 113.5, 113.2, 56.5, 56.1; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1060 [M?+?H]+. 4-((1E,4E)-5-(3,4-dimethoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5e) Yellow solid, yield 40%; mp: 198C200?C; IR (KBr, cm?1): 7.99 (d, 188.7, 151.7, 149.5, 145.5, 144.3, 140.7, 138.5, 130.5, 129.2, 128.1, 127.8, 126.8, 126.6, 124.2, 123.9, 112.1, 111.0, 56.5, 56.0; HRMS (ESI): Calcd for C19H20NO5S 374.1057, found 374.1055 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,3,4-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5f) Yellow solid, yield 35%; mp: 159C161?C; IR (KBr, cm?1): 7.98 (d, 188.7, 156.2, 153.5, 145.5, 142.3, Eluxadoline 140.9, 138.4, 138.1, 129.3, 129.0, 126.6, 124.5, 123.9, 121.3, 109.0, 61.9, 60.9, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1169 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(2,4,6-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5g) Yellow solid, yield 43%; mp: 249C251?C; IR (KBr, cm?1): 8.07C8.01 (m, 1H), 7.97 (d, 189.4, 161.8, 160.4, 145.1, 141.1, 137.3, 130.9, 129.2, 128.8, 126.6, 123.6, 115.9, 104.8, 90.1, 55.3, 54.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1166 [M?+?H]+. 4-((1E,4E)-3-oxo-5-(3,4,5-trimethoxyphenyl)penta-1,4-dien-1-yl)benzenesulfonamide (5h) Yellow solid, yield 45%; mp: 242C244?C; IR (KBr, cm?1): 8.11C7.99 (m, 2H), 7.97 (d, 188.6, 153.2, 143.3, 142.7, 138.6, 130.5, 129.3, 127.8, 126.8, 123.7, 119.1, 104.1, 60.6, 56.5; HRMS (ESI): Calcd for C20H22NO6S 404.1162, found 404.1164 [M?+?H]+. 4-((1E,4E)-5-(4-chlorophenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5i) Yellow solid, yield 43%; mp: 205C206?C; IR (KBr, cm?1): 7.99 (d, 188.9, 145.6, 142.3, 142.0, 141.6, 138.3, 135.6, 135.5, 134.1, 130.7, 129.5, 129.3, 128.1, 126.7, 126.6; HRMS (ESI): Calcd for C17H15ClNO3S 348.0456, found 348.0448 [M?+?H]+. 4-((1E,4E)-5-(2-fluoro-4-methoxyphenyl)-3-oxopenta-1,4-dien-1-yl)benzenesulfonamide (5j) Yellow solid, yield 40%; mp: 167C169?C; IR (KBr, cm?1): 7.99 (d, 188.7, 161.7, 158.6, 145.6, 143.3, 141.5, 138.5, 130.8, 128.3, 126.6, 123.7, 116.8, 111.2, 106.7, 55.7; HRMS (ESI): Calcd for C18H17FNO4S 362.0857, found 362.0856 [M?+?H]+. CA inhibition assay An Applied Photophysics stopped-flow instrument has been used for assaying the CA catalyzed CO2 hydration activity29. Phenol red (at a concentration of 0.2?mM) has been used as indicator, working at the absorbance maximum of 557?nm, with 20?mM Hepes (pH 7.5) as buffer, and 20?mM Na2SO4 (for maintaining constant the ionic strength), following the initial rates of the CA-catalysed CO2 hydration reaction for a.