| Abstract: | The synthesis of methyl N‐(1‐aza‐6‐oxaspiro2.5]oct‐1‐en‐2‐yl)‐L ‐prolinate ( 1e ) has been performed by consecutive treatment of methyl N‐(tetrahydro‐2H‐pyran‐4‐yl)thiocarbonyl]‐L ‐prolinate ( 5 ) with COCl2, 1,4‐diazabicyclo2.2.2]octane (DABCO), and NaN3 (Scheme 1). As the first example of a novel class of dipeptide synthons, 1e has been shown to undergo the expected reactions with carboxylic acids and thioacids (Scheme 2). The successful preparation of the nonapeptide 16 , which is an analogue of the C‐terminal nonapeptide of the antibiotic Trichovirin I 1B, proved that 1e can be used in peptide synthesis as a dipeptide building block (Scheme 3). The structure of 7 has been established by X‐ray crystal‐structure analysis (Figs. 1 and 2). |
