User/Group Creation and modification Permission in AD

I want to give access to help desk members group like below in a specific OU. Can you suggest please. I am using Win 2008 R2 AD.

1. Create groups

2. Modify/manage membership/change type of group.

3. deny delete group permission.

4. Create Users

5. Modify/manage user attributes. ex first name, last name etc

6. Deny delete user permission.