The reaction of 2-(7-chloro-1,8-naphthyrin-2-yl)-3-hydroxyisoindolin-1-one (I) with tert-butoxycarbonylmethylenetriphenylphosphorane (II) in refluxing toluene gives 2-(7-chloro-1,8-naphthyridin-2-yl)-3-oxoisoindolin-1-acetic acid tert-butyl ester (III), which is hydrolyzed with trifluoroacetic acid to the corresponding free acid (IV). Finally, this compound is condensed with 1,4-dioxa-8-azaspiro[4.5]decane (V) by means of diethyl phosphorocyanidate and triethylamine in DMF.

The reaction of 2-(7-chloro-1,8-naphthyrin-2-yl)-3-hydroxyisoindolin-1-one (I) with tert-butoxycarbonylmethylenetriphenylphosphorane (II) in refluxing toluene gives 2-(7-chloro-1,8-naphthyridin-2-yl)-3-oxoisoindolin-1-acetic acid tert-butyl ester (III), which is hydrolyzed with trifluoroacetic acid to the corresponding free acid (IV). Finally, this compound is condensed with 1,4-dioxa-8-azaspiro[4.5]decane (V) by means of diethyl phosphorocyanidate and triethylamine in DMF.

The reaction of 2-(7-chloro-1,8-naphthyrin-2-yl)-3-hydroxyisoindolin-1-one (I) with tert-butoxycarbonylmethylenetriphenylphosphorane (II) in refluxing toluene gives 2-(7-chloro-1,8-naphthyridin-2-yl)-3-oxoisoindolin-1-acetic acid tert-butyl ester (III), which is hydrolyzed with trifluoroacetic acid to the corresponding free acid (IV). Finally, this compound is condensed with 1,4-dioxa-8-azaspiro[4.5]decane (V) by means of diethyl phosphorocyanidate and triethylamine in DMF.