CYCC hasn't paid the 6% dividend on the preferred's in a while - there's accrued interest that will be paid back if they ever get a partnership deal - that dividend cant be dilluted.
Any sort of $$$ raise means they'll likely try to pay the back dated coupon payments they missed and there could be some nice upside - I havent looked at them in a while but i recall the potential $$$ needed to be paid out to those holders is pretty big - I was looking at them at $1 a few months ago - when CYCC popped. I'd have to dig around and find the terms when they were issuded - I cant recall what price they were issued at (so each coupon would be that * 6% annually (lets say its $10 for argunment) then they would have about $.60 in interest owed to those shareholders) the conversion price is so far away it's unlikely those "options" are worth much
About 3 million 6% preferred shares issued at $10 in 11/04 and only about 2 million preferred shares remain. The annual cumulative dividend looks to be about $1.2 million based on preferred shares remaining and the terms. All told, I don't see the preferred shares being a significant overhang limiting upside in the common stock.