The method 1, wherein step is carried out by treating the compound of the formula in {TAIL ~ DMF} in {HEAD ~ the presence} of 20 to 40 molar equivalents of POCl3 
The method 1 , wherein step is carried out by treating the compound of the formula in { TAIL ~ DMF } in { HEAD ~ the presence } of 20 to 40 molar equivalents of POCl3
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH