I guess the anyconnect installation 3.x and 4.x is awaiting an sysvinit environment (Like in Debian 7 Wheezy, Debian 8 Jessie has the systemd.). Downgrade from systemd to sysvinit should helps. There are a lot of manuals for this in the community, "apt-get install sysvinit-core systemd-shim systemd-sysv-" was the solution for me.
