Base-Catalyzed Ring Opening of N-Substituted 5-Isoxazolones¹

Tetrazolylhydrazides as Selective Fragment‐Like Inhibitors of the JumonjiC‐Domain‐Containing Histone Demethylase KDM4A

“…For the synthesis of ring‐methylated tetrazolylhydrazide 20 , diethyl 2‐(ethoxymethylene)malonate ( 17 ) was transformed into isoxazolone 18 , which could be easily converted in the course of a ring‐opening‐recyclization tandem reaction into ethyl tetrazolylacetate 19 . As before, this ester was subjected to hydrazinolysis, thus yielding the desired nonacidic tetrazole 20 (Scheme ), which expectedly did not show any notable activity against KDM4A at concentrations up to 200 and 400 μ m in the LANCE and FDH assays, respectively.…”

A short and efficient method for the synthesis of pyrimido[1,2-a]quinolines

“…s, OH, exchanged by D 2 O addition). 13 We are grateful for financial support from the Urmia University.…”

“…The reaction of isoxazol-5(2H)-ones, unsubstituted at C-3 atom, with a base is well known [13][14][15][16][17], and the various intermediates (Scheme 2) have been trapped to prepare a large number of heterocyclic systems [18,19]. However, the reaction of 3-substituted compounds with a base is not so well known, and the only reported reactions appear to be those reported by Doleschall [20] who alkylated the anion of ethyl 3-alkyl-2-methyl-5-oxoisoxazole-4-carboxylate in order to obtain γ-alkylated acetoacetates (Scheme 3).…”

Synthesis of new N-Benzoxazole and N-Benzothiazole derivatives of 3-(4-Substituted- phenyl)aminoisoxazol-5(2H)-ones and comparison of their base induced rearrangement

“…This compound was prepared as described for (10b) using the corresponding isoxazolones (8d) (100 mg, 0.34 mmol) and 2-chlorobenzothiazole (58 mg, 0.34 mmol) to afford the desired product as pale yellow (78 mg, 53%), after recrystalization from ethanol, mp 169-171 o C. 1 …”

“…The reaction of isoxazol-5(2H)-ones, unsubstituted at C-3, with base is well known [1][2][3][4][5] and the various intermediates have been trapped to prepare a large number of hetrocyclic system. [6][7][8][9] However, the reaction of 3-substituted compounds with base is not so well known, and the only reported reactions appear to be that described by Doleschall,10 who alkylated the anion of ethyl 2,3-dimethyl-2,5-dihydro-5-oxo-isoxazole-4-carboxylate, in order to obtain γ-alkylated acetoacetates.…”