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Some novel 4-(aryliidineamino)-5-(1-(4-isobutylphenyl) ethyl)-4-yl-4H-1,2,4-triazole-3-thiols were prepared from the  reaction of carbon-di-sulphide and hydrazine hydrate in water to produce thiocarbohydrazides. The thiocarbohydrazides is then refluxed with ibuprofen for 2 hour, followed by cooling to room temperature and washing with sodium bicarbonate solution to produce  5-(1-(4-isobutylphenyl) ethyl)-4H-1,2,4- triazole-3-thiole. It is then refluxed with different aldehydes in the presence of ethanol and HCl to produce the title compounds. The synthesized compounds are recrystallized from ethanol and are analyzed for their physical and spectral data. They are screened for their anti-microbial activity and it was found that the title compounds are found to have moderate to good antimicrobial activity.

Triazine backbone is present in a large number of bioactive substances and is known for their pharmacological activities like antimicrobial, antitumour and antiviral activity. Pyrazoles are another class of heterocyclic compounds associated with significant biological activities like anti-inflammatory, anticonvulsant and antimicrobial activity. In this view, it was proposed to synthesize some novel pyrazolo[3,4-e][1,2,4]triazines from 3,7-dimethyl pyrazolo[4,3-e] oxadiazine. In the current investigation, ethyl acetoacetate was condensed with hydrazine hydrate in ethanol to give 3-methylpyrazol-5-one. The pyrazole derivative was brominated by using bromine in acetic acid as brominating agent to give 4, 4- dibromo-3-methylpyrazol-5-one. This compound was then cyclized with acetic anhydride and hydrazine hydrate to get 3, 7-dimethyl pyrazolo[4,3-e]oxadiazine. This compound on further reaction with different substituted amines generates 4-(aryl/heteroaryl)-3,7-dimethyl-pyrazolo [3,4-e][1,2,4]triazines. The synthesized compounds were screened for their antibacterial and antifungal activity against S. aureus strain of Gram positive, E. coli the strain of Gram negative and A. niger strain of fungus by standard methods. The results suggest that the compounds 4a and 4c exhibited significant antifungal activity. Gentamycin, ciprofloxacin, cefotaxime and amphotericine B were used as standard drugs. The structures of the synthesized compounds were confirmed using analytical and spectral techniques (IR, 1H NMR and Mass spectral data). 

In the reaction of isoniazid with different aldehydes the respective N1-((un)-substituted benzilidene) isoniazid derivatives were obtained. Further reaction with N1-((un)-substituted benzilidene) isoniazids and hydrazine hydrate yielded dihydroformazans. These dihydroformazans on reaction  with N-phenylisocynodichloride in chloroform medium led to the creation of 1, 2, 4-triazolines. All these 1,2,4-triazolines were further converted into their acetyl derivatives by reacting them with acetic anhydride. The structures of all new compounds were confirmed by using elemental and spectral analysis. All the compounds were screened for their antifungal activities.