Total syntheses of (+)-monomorine I and (−)-indolizidine 195B from sulfinimine-derived 3-oxo pyrrolidine 2-phosphonates

Indolizidine alkaloids (+)-monomorine I (1) and (−)-indolizidine 195B (2), having cis and trans relationships of the C-3 and C-9 substituents, respectively, were prepared from the sulfinimine-derived chiral building blocks N-sulfinyl δ-amino β-ketophosphonate and 3-oxo pyrrolidine 2-phosphonate.