The synthesis of unnatural amino acids with small side-chain functionalities usable for further transformations is highly demanding for the expansion of the genetic code and other possible biotechnological applications. To this end, we wanted to report the utility of an unexplored unnatural amino acid, isothiocyanyl alanine (NCSAla = Ita), for the synthesis of another class of unnatural amino acids, thioureayl alanines (TUAla = Tua). The synthesis of a third class of unnatural amino acids, amino tetrazolyl alanines (ATzAla = Ata), in a very good yield was subsequently achieved utilizing thioureayl alanines. Thus, a variety of aliphatic- and aromatic-substituted thioureayl alanines and aromatic-substituted amino tetrazolyl alanines were successfully synthesized in good to excellent yields. The photophysical properties of three of the fluorescent unnatural amino acids from two classes were also studied and presented herein.
|Number of pages||10|
|Journal||Journal of Organic Chemistry|
|State||Published - 1 Dec 2017|
Bibliographical noteFunding Information:
The authors thank the Department of Biotechnology (DBT: BT/PR16620/NER/95/223/2015), New Delhi, Government of India for the generous funding. S.D. thanks the IIT Guwahati for a fellowship. The CIF, IITG is gratefully acknowledged for the 600 MHz NMR facility.
© 2017 American Chemical Society.