How Can I Add Attributes To An Active Directory Group

Question

I have an Active Directory container of security groups.  I would like to add additional properties to the security groups such as the following:

- Product Title
- Product Version
- Product Description
- Manufacturer

How can I add attributes such as those listed above to an Active Directory security group?  And, once added, how can I query them from the security group? I am using Visual Studio 2012 Professional with C#.  My Active Directory server is on a Windows 2008 R2 server. 

I am looking for a solution in C#.

Thanks in advance.