Stereoselective synthesis of renin inhibitor BILA 2157 BS

We have developed a convergent and stereoselective synthesis of orally active renin inhibitor BILA 2157 BS. Three building blocks were used to generate the basic skeleton of the inhibitor. The key feature consisted of the late elaboration of the 2-amino-4-thiazolyl heterocycle from a vinylbromide precursor. The synthetic sequence, which required a total of 22 chemical steps, provided 0.6 kg of BILA 2157 BS in 7.3% overall yield.Key words: renin, inhibitor, peptidomimetic, stereoselective synthesis.