Polycyclic N-heterocyclic compounds 74: Rearrangement reaction of 5-amino-1,2-dihydrofuro[2,3-c]isoquinolines with α, ω-dibromoalkanes and evaluation of product bronchodilator activity

Reaction of 5-amino-1,2-dihydrofuro[2,3-c]isoquinolines with 1,2-dibromoethane and 1,3-dibromopropane in the presence of a base afforded 2′,13′-dihydrospiro[cyclopropane-1,6′(5′H)-imidazo[2, 1-a]isoquinolin]-5′-ones and 3′,4′-dihydro-2′H- spiro[cyclopropane-1,7′ (6′H)-pyrimido[2,1-a]isoquinolin]-6′- ones, respectively. Certain of the products showed significant bronchodilator activity.