how to synchronize the data R/3 to CRM

Hi Experts

Please sagest me how can i synchronize the data  R/3  to CRM

To create the inquiry  in r/3 we are sending the data from CRM to R/3 through BAPI,

once inquiry created in r/3 we are updating the data r/3 to CRM,Because based on inquiry  status we are sending the mails  escalations from CRM

but if inquiry are inquiry line items are deleted in r/3 how can i synchronize the data from R/3 to CRM,