Atribute validation when saving in CRM_UI

Hi experts,

I need to validate when the attribute "Send DDVV" is marked that the email field is filled. If it is padded, I will add a record in a Z table. Then I do not know if the validation should be included in the "SAVE" button or in another part of the component.

If it is in the "SAVE" button where the validation would be implemented?

Regards.