Synthesis of some new pyranoquinoline derivatives of potential antineoplastic activity

ABSTRACT

Few reports concerning the antineoplastic activity of certain pyranoquinolines have been reviewed. In the present work, synthesis of some pyranoquinoline derivatives as antitumour agents is described. The key intermediate 10-amino-3-oxo- pyrano[3,2-t] quinoline-9-carbonitrile III was prepared. Acylation of the amino compound III afforded the corresponding amides IV, while its reaction. with certain aromatic aldehydes gave the 10-arylidineamino derivatives V. Also, the reaction of III with triethylorthofonnate yielded the ethoxymethyleneamino derivative VI, which when subjected to a substitution reaction with hydrazine hydrate or methylamine, afforded compounds VII and VIII, respectively. Reaction of the aminonitrile derivative with carbon disulfide yielded the tetracyclic structure pyranopyrimidoquinoline IX. Additionally, heating 6-aminocoumarin I with arylidine derivatives afforded pyranoquinoline-9-carbonitriles X and 9-carboxylates XI. The nitrilo derivative XII was prepared from the reaction of I with ethyl ethoxymethylene cyanoacetate, which upon alkylation with 2-chloroethanol yielded the key compound XIII. Acylation and alkylation of this compound, in addition to its chlorination and subsequent reaction of the chloro intermediate with various amines ended up with the desired compounds XIV, XV, XVI and XVII