Efficient method for the synthesis of bisaminoethanethiols and their pyrrole conjugates

By following the protection and deprotection approach, an efficient method for the preparation of bisaminoethanethiol ligands (N2S2) is discussed. In our attempts to synthesize certain nonpeptide analogs of neurotensin, molde l studies were performed by using these ligands for preparing the correspon ding pyrrole based conjugates. This methodology provides an alternate appro ach for developing various target specific agents that cross the blood brai n barrier.