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A series of new 4-aryl-2'-[(4-hydroxyphenyl)thio]-6oxo-1,6-dihydro- 2,4'-bipyridine-5-carbonitriles (3a-k) and 6-amino-4aryl-2'-[(4-hydroxyphenyl) thio]-2,4'-bipyridine-5-carbonitriles (4a-h) were synthesized from 4-hydroxythiophenol (1). The reaction of 4-hydroxythiophenol with 4-acetyl-2-chloropyridine yielded 1-{2-[(4-hydroxyphenyl)thio]pyridin-4-yl}ethanone (2). Further treatment of 2 with ethyl cyanoacetate in the presence of ammonium acetate with various aromatic aldehydes furnished the compounds 3a-k. On the other hand, condensation of 2 with aromatic aldehydes in the presence of alcoholic malononitrile in ammonium acetate gave compounds 4a-h. The structures of the newly synthesized compounds were established on the basis of their elemental analysis, as well as their IR, 1H- and 13C-NMR and mass spectral data. All the title compounds were subjected to in vitro antibacterial testing against two strains and antifungal screening against two fungi. Some of the compounds showed promising activity.

A series of new 2-[(4-alkylthio/alkylsulfonyl phenoxy) methyl]-5-substituted-1,3,4-oxadiazoles 4a–y , 5a–h ) have been synthesized from 4-alkylthio phenol ( 1a–b ) through a multi-step reaction sequence. Compounds 1a–b reacted with ethyl chloroacetate to give ethyl [4-(alkylthio) phenoxy] acetate ( 2a–b ) which on oxidation yielded ethyl [4-(alkylsulfonyl)phenoxy]acetate ( 2c–d ). They were readily converted to the corresponding hydrazides 3a–d , and then cyclized to the title compounds 2-{[4-(alkylthio/alkylsulfonyl) phenoxy] methyl}-5-aryl-1,3,4-oxadiazoles ( 4a–y ) by condensing with aromatic carboxylic acids. Further, 3a–b , on condensation with carbon disulphide afforded the title compounds 2-{[4-(alkylthio) phenoxy]methyl}-1,3,4-oxadiazole-5-thiols( 5a–b ), which on alkylation yielded the title compounds 2-[(4-alkylthio phenoxy) methyl]-1,3,4-oxadiazole-5-alkyl thiols ( 5c–f ), while with chloroacetic acid gave the target compounds 2-[(4-alkylthio phenoxy) methyl]-1,3,4-oxadiazole-5-thioacetic acid ...

In the title molecule, C16H14OS, the dihedral angle between the phenyl and benzene rings is 3.81 (15)°. The H atoms of the central enone group are trans. The propenone unit makes dihedral angles of 11.73 (18) and 11.62 (17)° with the benzene and phenyl rings, respectively. The crystal structure is stabilized by weak C—H...O and C—H...π interactions.

Thirty one new 6-aryl-3-{(4-substituted phenoxy) methyl}-1,2,4-triazolo[3,4- b ]-1,3,4-thiadiazoles ( 6a – s ) and 6-aryl-3-{(4-substituted phenoxy methyl}-7 H -1,2,4-triazolo[3,4- b ]-1,3,4-thiadiazines ( 7a – l ) have been synthesized from 4-thioalkyl phenols ( 1a – b ) through a multi-step reaction sequence. Compounds 1a – b reacted with ethyl chloroacetate in presence of acetone and potassium carbonate to give ethyl [4-(thioalkyl) phenoxy] acetates ( 2a – b ). Further, 2a was oxidized to [4-(methyl sulphonyl) phenoxy] acetate ( 2c ) using hydrogen peroxide in acetic acid. Reactions of ( 2a – c ) with hydrazine hydrate in alcoholic medium furnished 2-[4-thiosubstituted phenoxy] acetohydrazides ( 3a – b ) and 2-[4-methyl sulphonyl phenoxy] acetohydrazide ( 3c ) which on treatment with carbon disulphide and methanolic potassium hydroxide yielded corresponding potassium dithiocarbazates ( 4a – c ). They were then converted to 4-amino-5-{(4-thioalkyl phenoxy) methyl}-4 H -1,2,4-triazole-3-thiols ( 5a – b ) and 4-amino-5-{(4-methyl sulphonyl phenoxy) methyl}-4 H -1,2,4-triazole-3-thiol ( 5c ) by refluxing them with aqueous hydrazine hydrate. The title compounds 6a – s were prepared by condensing 5a – c with various aromatic carboxylic acids in presence of phosphorus oxychloride. The intermediates 5a – c , on condensation with various substituted phenacyl bromides afforded a series of title compounds ( 7a – l ). The structures of new compounds 2a – 7l were established on the basis of their elemental analysis, IR, 1 H NMR, 13 C NMR and mass spectral data. All the title compounds were subjected to in vitro antibacterial testing against four pathogenic strains and antifungal screening against three fungi. Preliminary results indicate that some of them exhibited promising activities and they deserve more consideration as potential antimicrobials.