{HEAD ~ Carbacephem β lactam antibiotics} having {TAIL ~ the following chemical structures} and are disclosed: 
having
{ HEAD ~ Carbacephem β lactam antibiotics } having { TAIL ~ the following chemical structures } and are disclosed :
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH