Also, {HEAD ~ a salt} of a non chiral auxiliary can be used as a cyclizing agent in a process using {TAIL ~ a starting material} containing a chiral auxiliary 
Also , { HEAD ~ a salt } of a non chiral auxiliary can be used as a cyclizing agent in a process using { TAIL ~ a starting material } containing a chiral auxiliary
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH