Synthesis of 3-(2-aminoethyl)-5-hydroxy-1H-pyrazole derivatives

Abstract

Treatment of β-keto ester 8 with hydrazines 9a-g gave 1'-substituted tert-butyl 2-(5-hydroxy-1H-pyrazol-3-yl)ethylcarbamates 10a-e and 2-(5-oxo-2,5-dihydro-1H-pyrazol-3-yl)ethylcarbamates 11f,g. Acidolytic deprotection of 10b,c afforded the corresponding 3-(2-aminoethyl)-5-hydroxy-1H-pyrazoles 6b,c in good yields. Acylation of 6 gave either the N-acyl compounds 12b,c and 13c, or the N,O-diacyl derivative 14. Next, three N,N-dialkyl analogues 15a,b and 26c were prepared from dimethyl acetone-1,3-dicarboxylate 21 via condensation with hydrazines 9a and 9h followed by hydrolysis of the esters 22a,b, amidation of the carboxylic acids 23a,b, and reduction of the tertiary carboxamides 24a and 25b,c.

Microwave Assisted Synthesis, Characterization of New Heterocyclic Compounds and Evaluation as Anti Breast Cancer

“…Also, all 13 C NMR spectrum of the Heterocyclic compounds showed signals at (50 -70) ppm chemical shift due to the (OCH 3 ) and (OCH 2 ) groups, Z7, Z8, and Z9 showed single peck at (21) ppm for CH 3 group [32]. Moreover, 13 C NMR spectra for all prepared chalcones showed signals within region (108-150) ppm for aromatic system [33,34] 13 C NMR data of these compounds are summarized in Table 5 and numbering of carbon atoms in Fig.…”