Since you're looking at direct hypothetical flights (Santo Domingo- Bridgetown), if you flew from Porto Novo, Benin to Luanda, Angola you'd fly from the nearest international airport in Cotonou which means that the plane would just pass over Sao Tome. There's a few more like Port Moresby - Nadi, Paramaribo- Brasilia is a weird one, in a similar vein but much much cooler you also have Antananarivo - Cairns, Australia maybe even Antananarivo - Mogadishu if you're feeling lucky and if you want to be controversial try Sao Paulo - Sydney.
I feel like such an idiot right now. I know Sarajevo is in Bosnia but for some reason today I kept thinking it was in Serbia... which led me to type-in every country in the Balkans EXCEPT for Serbia :P