http://stackoverflow.com/questions/15750711/connecting-to-sql-server-2012-using-sqlalchemy-and-pyodbc

Install unixodbc version > 2.3.0

wget ftp://ftp.unixodbc.org/pub/unixODBC/unixODBC-2.3.4.tar.gz
tar zxvf unixODBC-2.3.4.tar.gz 
cd unixODBC-2.3.4/
./configure --enable-gui=no --enable-drivers=no --enable-iconv --with-iconv-char-enc=UTF8 --with-iconv-ucode-enc=UTF16LE --libdir=/usr/lib/x86_64-linux-gnu --prefix=/usr --sysconfdir=/etc
make
sudo make install

Download Microsoft ODBC Driver 11 for SQL Server® - RedHat Linux

/bin/bash install.sh verify