Coatec was launched in Japan for acute cardiac insufficiency in cases
resistant to other treatments. There are three related synthetic routes, 5-6 steps
each, to loprinone all converging on 1-(imidazo[1,2a]pyridyl-6-yl)-Zpropanone as an
advanced intermediate. It is a potent and selective inhibitor of PDE Ⅲ and a long
lasting, orally active, positive inotropic agent. The PDE Ⅲ inhibition caused
increased levels of CAMP which leads to the positive inotropic effect that was not
altered by β or H2-preceptor antagonists. It was 100 times less potent at PDE I and
PDE Ⅱ with no Na-K-ATPase activity. Improved hemodynamic parameters with slight
changes in heart rate and blood pressure were seen in vivo. It is not mutagenic and
its primary metabolite was less active.
