Pseudocode, by definition, is pseudo, not real. So there is no strictly defined syntax. So it isn't possible to check the syntax programmatically.
I don't know of any program that will create Nassi-Shneidermann diagrams (PSD's) or flow charts from pseudocode, sorry.
Are there any programs out there that will create a Flow Chart by just inputing Psuedocode? Or is there a program that can check Psuedocode to make sure there is no Syntax errer?