1. Create principal with backslash using kadmin.local:

kadmin.local:  addprinc anand\\slash@DOMAIN
WARNING: no policy specified for anandslash@DOMAIN; defaulting to no policy
Enter password for principal "anand\\slash@DOMAIN": 
Re-enter password for principal "anand\\slash@DOMAIN": 
Principal "anand\\slash@DOMAIN" created.

2. Create a keytab for that principal using ktutil:

# ktutil
ktutil:  addent -password -p anand\\slash@DOMAIN -k 1 -e des3-cbc-sha1
Password for anand\\slash@DOMAIN: 
ktutil:  wkt /tmp/slash.keytab
[root@anand-cm-1 ~]# klist -kte /tmp/slash.keytab
Keytab name: FILE:/tmp/slash.keytab
KVNO Timestamp         Principal
---- ----------------- --------------------------------------------------------
   1 01/06/17 12:53:30 anand\\slash@DOMAIN (des3-cbc-sha1) 

3. Try to use that keytab with kinit:

# kinit -k -t /tmp/slash.keytab -p anand\\slash@DOMAIN
kinit: Keytab contains no suitable keys for anandslash@DOMAIN while getting initial credentials