Looks strange, you can test this code in any WEB java script demo:
With the code .replace(/\//g, "_").replace(/\\/g, "_").replace(/\(/g, "_").replace(/\)/g, "_")
593\594-B-29-B(DÜK
The result is:
593_594-B-29-B_DÜK
May be SAP javascript works incorrectly here: .replace(/\\/g, "_")
Vadim