Salary negotiations - Analyst/Associate

Hey everybody,

I just entered into salary negotiations for a position into a $300M infra fund based in Paris.
Although I dont have the typical background; few years in sales & trading + operational experience in business strategy + MBA degree from top 5 European B.School, the fund is offering me an analyst position at 50K per year base. That's a 50% cut on my previous salary.
Although I knew that such a career shift would mean a little hair cut I feel like this is a bit too much!
How much can I negotiate in terms of salary or even title? And how fast is the progression usually?

Any advice would be greatly appreciated.

Thank you.