Reactions of 4-alkylidene (arylidene)-1-phenylpyrazolidine-3,5-dione

Abstract

Reactions of 4-alkylidene(arylidene)-1-phenylpyrazolidine-3,5-dione with oxidizing (chromium trioxide/acetic acid) as well as with reducing (sodium borohydride/methanol) agents were carried out. Phenylhydrazine reacted with 4-arylidene-1-phenylpyrazolidine-3,5-diones via fission of exo C=C bond to give 1-phenylpyrazolidine-3,5-dione and the corresponding aryl hydrazones.Condensation of 1-phenyl-3,5-pyrazolidinedione (1) with carbonyl compounds readily give 4-alkylidene(arylidene)-1-phenyl-3,5-pyrazolidinediones 2 which were subjected to several investigations [1][2][3][4]. The purpose of this paper is to develop and study new products derived from 2 by oxidation, reduction, and reaction with phenylhydrazine.

Green synthetic investigation and spectral characterization of some spiro pyrazolidine‐based heterocycles with potential biological activity

“…Here a modified method was employed to improve the isolated yield of the desired compounds compared with the previous work. [20,22] Heating of 3 with different carbonyl compounds under solvent-free condition gave excellent yield of 4-alkylidene (4a and 4b) or 4-arylidene derivatives (4c-h) (chalcone derivatives) (Scheme 2) compared with reported literature. [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] 4-(2 0 -Methoxylbenzylidene)-1-phenyl-3,5-pyrazolidinedione (4e) was ascertained through spectral analysis as 1 HNMR, 13 CNMR, DEPT-135, COSY, HSQC, and HMBC.…”

“…The physical and spectral data of compounds 5a-h were identical to the reported data. [22] 2 0 ,2 0 -Dimethyl-1-phenyl-3,5-dioxo-1,2,3,5-tetrahydrospiropyrazole-4,3 0 -oxirane (5a) was obtained in good yield and for the first time by epoxidation of 4-isopyropylidene-1-phenyl-3,5-pyrazolidinedione (4a) using MMPP in ethanol or tetrahydrofuran as solvent in neutral medium. This may be attributed to the increased activity of the 4-exocyclic double bond due to the presence of two methyl groups.…”

The Reaction of 1‐Phenylpyrazolidine‐3,5‐dione with Active Nitriles Using Phase Transfer Catalysis Conditions Technique

“…Pyranopyrazoles, 1,3‐thiazines, thiazoles , thienopyrazoles , and furopyrazole represent important classes of heterocycles, which have been developed for different purposes in the pharmaceutical field. In continuation of our previous works, which had dealt with using active nitriles in synthesis of polyfused‐ and spiropyrazoles, herein, we report the synthesis of pyrano[2,3‐ c ]pyrazole, thiazole, 1,3‐thiazine, 1,3‐oxothiinopyrazole, and furo[2,3‐ c ]pyrazole derivatives starting with 1‐phenylpyrazolidine‐3,5‐dione.…”

“…3,5‐Pyrazolidendiones were reported to possess antibacterial, anti‐inflammatory, antiviral, antimicrobial and uricosuria properties. Pyranopyrazoles, 1,3‐thiazines, thiazoles , thienopyrazoles , and furopyrazole represent important classes of heterocycles, which have been developed for different purposes in the pharmaceutical field.…”

Synthesis, crystal structure, and fungicidal activity of novel 1,5‐diaryl‐1H‐pyrazol‐3‐oxyacetate derivatives

“…Then the reaction of arylpropiolic acids and their esters with phenylhydrazine became one of the most popular methods for the synthesis of 1,5‐diaryl‐1 H ‐pyrazol‐3‐ols [8–11]. In recent years, synthesis of 1,5‐diaryl‐1 H ‐pyrazol‐3‐ols by the reactions of 4‐arylidene‐1‐phenyl‐3,5‐ pyrazolidinediones with oxidizing agents has been achieved [12]. However, very few representatives of biologically active 1,5‐diaryl‐1 H ‐pyrazol‐3‐oxyacetate derivatives have hitherto been described in the literature.…”