These compounds are designated in scheme 3 as having the formula {HEAD ~ VII A. Example} 2 of this application describes the preparation of {TAIL ~ the S enantiomer} by the method shown in scheme 3 
These compounds are designated in scheme 3 as having the formula { HEAD ~ VII A. Example } 2 of this application describes the preparation of { TAIL ~ the S enantiomer } by the method shown in scheme 3
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH