(-)-Antirhine 2 was synthesized in an efficient and stereocontrolled f
ashion from the readily available (1R-2S)-cyclohexene dimethanol monoa
cetate 6. A key step was the regio- and stereoselective Pictet Spengle
r cyclization of the masked dialdehyde 12 to the indoloquinolizidinone
13.