Synlett 2010(17): 2549-2552  
DOI: 10.1055/s-0030-1258572
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

A Straightforward Route to Novel α,α-Disubstituted Tetrahydrofuran β-Amino Acids and Spirodiketopiperazines from Sugar Lactones

Raquel G. Soengas*
Departmento de Química Fundamental, Universidad de A Coruña, Campus de A Zapateira, s/n, 15071 A Coruña, Spain
Fax: +34(981)167065; e-Mail: rsoengas@udc.es;
Further Information

Publication History

Received 13 August 2010
Publication Date:
23 September 2010 (online)

Abstract

Indium-mediated Reformatsky reactions of aldonolactones with ethyl α-bromoisobutyrate allowed the synthesis of ulo­sonic acid esters, which were readily transformed into the corresponding tetrahydrofuran β-azido esters in a stereoselective fashion. This approach provided monomeric components suitable for oligomerization to the carbopeptoid class of foldamers and prompted the total synthesis of the attractive novel spiro diketo­piperazine, which can be regarded as a spironucleoside.

11

Azido ester 14; mp 88-90 ˚C (Et2O-hexane).