Some reactions of 3-methyl- 1- phenyl-4- [phenylamino-thiocarbonyl] -2- pyrazolin-5-one

The title compound 1 was prepared via reaction of 3-methyl-1-phenyl-2-pyrazolin-5-one with phenylisothiocyanate. Then, it was converted to pyrazolopyrazole, pyrazolopyrimidine, pyrazolopyridine, and the amino derivatives through reaction with hydrazines, urea, thiourea, malononitrile and aromatic amines. Compound [1] prepared via addition of activated nucleophilic carbon of 3-methyl-1-phenyl-2-pyrazolin-5-one to the electrophilic carbon of phenylisothiocyanate seemed to be suitable to annulation through its reactive center. The reaction of [1] with hydrazine hydrate and phenyl-hydrazine in boiling ethanol gave the pyrazolopyrazole derivatives [2a] and [2b], respectively. The mass spectrum of [2a] showed the parent ion peak at m/z 289 and the following abundant peaks 185, 105, 91, 77, and 51. Structure of [2a] was further established by its reaction with ethyl bromoacetate to give [3]. The latter afforded the hydrazide derivative [4] on reaction with hydrazine hydrate

Reactions of N, N'-diarylethylenediimines with grignard reagents, phenylisocyanate and succinic anhydride, part III

In previous work, it has been reported that cinnamylideneanilines [-C = C-C = N] consumed one mole of Grignard reagents to give the 1,4-adducts. In order to study the effect of substituent on a basic nitrogen atom connected to the terminal carbon atom, in the above conjugated system, we have investigated the reaction of Grignard reagents on N,N'-diarylethylenediimines [la-b]. Thus, treatment of la with benzylmagnesium chloride and/or Ib with benzylmagnesium chloride, p-anisylmagnesium bromide and cyclohexylmagnesium bromide provided the diadducts [IIa-d], via 1,2-addition of 2 moles of the Grignard reagents to the system -N = C-C = N- with the formation of the intermediate magnesium salt which upon acidification and decomposition gave [II]

Synthesis of some new [substituted phenacyl] -3,5dimethyl-pyrazole-1-acetic acid and 4-pyrazol-4-yl-pyridazinones and the study of their antibacterial activities

Beta a roylacrylic acids [1] react with 3,5-dimethylpyrazole to give [mono - and di-substituted halophenacyl]-3,5-dimethylpyrazole-1-acetic acid [2]. Reactions of 2 with hydrazine hydrate and phenyl hydrazine afford the corresponding 4-pyrazoi 1-yl-pyridazinone [3 and 4]. Reactions of 4-pyrazol-l-yl-pyridazinones [3] with dimethylsulfate, diethylsulfate, ethyl bromoacetate, phosphorus oxychloride, phosphorus pentasulfide and bromine-acetic acid mixture have been described. Reactions of 2 with hydroxyl-amine hydrochloride in ethanol and pyridine affords the oxime and oxazinone derivatives. Dehydration of 2 yields the furanone derivative. The in vitro antibacterial screening reveals substantial activities against Gram-positive and Gram-negative bacteria for compounds 2a, 3b and 4b; while compounds 2b and 5 b are inactive

Studies on some B-aroyl- [4 [1,3-disubstituted-2-pyrazolin-5-one]] propionic acids

Baroylarcylic acids [I] react with 1, 3-disubstituted-2-pyrazolin-5-ones in dry benzene to give the adducts II. Estrification of lid with diazomethane gives the corresponding methyl ester [III]. Reactions of II with hydrazine hydrate and phenylhydrazine afford the corresponding pyridazinones [V and VI]. Dehydration of II yield the butenolides [VII]. The reactions of pyrida-zinones V with anisaldehyde, ethyl bromoacetate, diethyl sulfate and Grignard reagents are also described. The in vitro antibacterial screening reveals substantial activities against Gram-positive and Gram-negative bacteria for compounds lie and lid; while compounds IIa, IIb and Vb are inactive