Calculated Formula RollUpSum

I am trying to create a Roll Up Sum if the Opportunity Sale Stage is Prospecting, Qualification etc

ifElse(

equal(related($ems_parent_opportunities_opportunities,"sales_stage"),"Prospecting","Qualification","Proposal/ Price Quote","Converting","Closed Won")
rollupConditionalSum($ems_parent_opportunities_opportunities,"amount")

).

However I get the error message:

Invalid Formula
ifElse( equal(related($ems_parent_opportunities_opportunities,"sales_stage"),"Prospecting","Qualification","Proposal/ Price Quote","Converting","Closed Won") rollupConditionalSum($ems_parent_opportunities_opportunities,"amount") ).: Syntax Error, no close parentheses found.
Can anyone help to see where i'm missing aclosed bracket??
Thanks so much