restrict who can send emails to an email address

[Sunny]

Hi,

Is there an option in cyrus that can restrict who can send emails to an 
email address?

e.g

the mail alias everyone at mycompany.com contains all the members in the 
organisation - I would like to restrict who can send emails to 
everyone at mycompany.com, ideally granular control i.e. boss at mycompany.com 
pa at mycompany.com or if that's not possible only internal users 
*@mycompany.com (i.e. no external address is allowed to send to 
everyone at mycompany.com).

Regards