Commercially available (—)-β-hydrastine (1) was O-demethylated to the tetraphenol 3 followed by bis-O-methylenation or complete O-methylation to afford the rare phthalide alkaloid (—)-bicuculline (4) and the new phthalideisoquinoline (—)-cordrastine II (5), respectively. Alkaline isomerization provided the corresponding C-9 epimers capnoidine (6) and (—)-cordrastine I (7). An X-ray analysis of 4 HBr confirmed the assignments of absolute configuration. © 1972, American Chemical Society. All rights reserved.