Base.pm:
package Base;
sub method1 {
    # Insert code here
};

Foo.pm:
package Foo;
use Base;
@ISA = qw(Base);

Bar.pm:
package Bar;
use Base;
@ISA = qw(Base);

Main.pm
...
foreach my $classname qw(Foo Bar) {
    $classname->method1;
}