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