Pollenopyrroside A and capparisine B, two diastereoisomers of pyrrole spiroketal alkaloids
isolated from Brassica campestris pollen and Capparis spinosa, were synthesized by an improved microwave-assisted bishydroxymethylation of pyrrole
and acid-catalyzed spirocyclization as key steps with total yields of 2.7 and 8.8%,
respectively.
Key words
alkaloids - spiroketals - natural products - total synthesis - microwave-assisted
reaction