1268872-34-9Relevant academic research and scientific papers
A rapid and convenient synthesis of naphthyridinoyl pyrazolidinones under microwave irradiation condition
Chaitanya, Muggu V.S.R.K.,Dubey, Pramod K.
, p. 368 - 374 (2012/08/28)
Microwave-assisted synthesis of naphthyridinoylpyrazolidinones (7a-7j) has been achieved rapidly via the reaction of naphthyridine hydrazide (4) with different β-keto esters and ethoxymethylenemalonic ester (EMME) (5a-5e). Initially, the reaction of naphthyridine hydrazide (4) with various β-keto esters under microwave irradiation for 5 mins at 130oC results in the formation of condensed products 6a-6j. This condensation was followed by cyclization, also, in diphenyl ether under microwave irradiation for 10 mins at 230-250oC, yielding the corresponding cyclized products 7a-7j. Alternatively, both reactants 4 and each of the β -keto esters/EMME (5a-5e) were treated in diphenyl ether under microwave irradiation for 15 mins at 230-250oC giving the target molecules 7a-7j as one-pot reaction in good yields.
A facile and convenient synthesis of naphthyridinoyl pyrazoles
Chaitanya,Dubey
, p. 109 - 112 (2013/09/23)
The reaction of naphthyridine hydrazide (4) with each of the different β-keto esters like ethyl 2-chloroacetoacetate (5), ethyl benzoylacetate (6) and ethyl 4-chloroacetoacetate (7) and with ethoxymethylenemalonic ester (8), independently, in ethanol, resulted in the formation of condensed products 2-chloro-3-[4-oxo-1,4-dihydro-[1,8] naphthyridine-3-carbonyl hydrazono]-butyric acid ethyl ester (9), 3-[(4-oxo-1,4-dihydro-[1,8] naphthyridine-3-carbonyl)- hydrazono]-3-phenyl propionic acid ethyl ester (10), 4-chloro-3-[(4-oxo-1,4- dihydro-[1,8] naphthyridine-3-carbonyl)-hydrazono]-butyric acid ethyl ester (11) and 2-[N-(6-bromo-4-oxo-1,4-diydro-[1,8] naphtyiridine-3-carbonyl- hydrazinomethylene)-malonic acid diethyl ester] (12) respectively. Each of these on heating with diphenyl ether yielded the corresponding cyclized products 3-(4-chloro-3-methyl-5-oxo-4,5-dihydro-pyrazole-1-carbonyl)-1H-[1,8] naphthyridin-4-ohe (13), 3-(5-oxo-3-phenyl-4,5-dihydro-pyrazole-1-carbonyl)-1H- [1,8] naphthyridine-4-one (14), 3-(3-chloromethyl-5-oxo-4,5-dihydropyrazole-1- carbonyl)-1 H-[1,8] naphthyridine-4-one (15) and 3-(4-chloro-3-methyl-5-oxo-4,5- dihydropyrazole-1-carbonyl)-1H-[1,8] naphthyridin-4-one (16). Alternatively, treatment of naphthyridine hydrazide (4) with each of the β-keto esters 5,6 & 7 and with EMME (8) directly in diphenylether at 2507deg; as one-pot reaction, gave the final products 13,14,15 & 16 in good yields.
