In particular, for example, a benzyl or methoxymethyl group is used as {HEAD ~ the protective group} and {TAIL ~ a Grignard reagent} is used as the organometallic reagent 
In particular , for example , a benzyl or methoxymethyl group is used as { HEAD ~ the protective group } and { TAIL ~ a Grignard reagent } is used as the organometallic reagent
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH