I received an error, but I finally managed it. I don't know if it is the right approach, but it seems to work:
......
import flash.utils.getDefinitionByName;
import flash.utils.getQualifiedClassName;
......
var ClassRef: Class = Class(getDefinitionByName(getQualifiedClassName(match[i])));
var newMC:* = new ClassRef();
addChild(newMC);