The asym. synthesis of 1,3-lactol-bridged tetrahydroisoquinolines I [R = SiMe2CMe3, CH2Ph; R1 = CH2CH(CO2Me)2; R2 = CO2CH2Ph] was developed. Subsequent cyclizations of I (R = SiMe2CMe3, CH2Ph) under acidic conditions lead to the formation of a tricyclic enamides II [R = SiMe2CMe3, CH2Ph; R1 = CH2CH(CO2Me)2; R2 = CO2CH2Ph]. II [R = CH2Ph, R1 = CH2CH(CO2Me)2, R2 = CO2CH2Ph] was in turn converted to a tetracyclic compd. III. [on SciFinder (R)]