как то так :

всю сетку кроме 51 50 Redirect на 77.88.21.3

access-list 140 remark "www-redirect"
access-list 140 deny   tcp host 192.168.149.51 any eq www
access-list 140 deny   tcp host 192.168.149.50 any eq www
access-list 140 permit tcp 192.168.149.0 0.0.0.255 any eq www
access-list 140 deny   tcp any any

route-map www-redirect permit 10
match ip address 140
set ip next-hop 77.88.21.3

interface Vlan1

ip policy route-map www-redirect