%0 Journal Article %T Synthetic studies towards bottromycin %A Stefanie Ackermann %A Hans-Georg Lerchen %A Dieter H£¿bich %A Angelika Ullrich %J Beilstein Journal of Organic Chemistry %D 2012 %I %R 10.3762/bjoc.8.189 %X Thio-Ugi reactions are described as an excellent synthetic tool for the synthesis of sterically highly hindered endothiopeptides. S-Methylation and subsequent amidine formation can be carried out in an inter- as well as in an intramolecular fashion. The intramolecular approach allows the synthesis of the bottromycin ring system in a straightforward manner. %K amidines %K antibiotics %K bottromycin %K peptides %K thiopeptides %K Ugi reactions %U http://dx.doi.org/10.3762/bjoc.8.189